Last updated: 17 February 2010
Published in: Managing a project | Creating new digital media
Tags: copyright | digital collections | digital preservation | digital preservation policy | moral rights | performance rights | podcasts | recording rights | screen capture | sound recordings | video | workflow

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Summary

This advice document provides some basic information on rights issues associated with creating time-based digital media resources. By time-based we mean resources that change over time - including spoken audio, music, animation, and video - as opposed to still images or screen shots, which do not change over time. Rights issues include copyright, recording rights, moral rights and performance rights.

Please note: The remit of JISC Digital Media includes the provision of practical advice and guidance to the FE and HE communities on copyright matters. Staff at JISC Digital Media are not lawyers and all advice is provided on that basis. Should you wish to receive a legal opinion in relation to a copyright matter then you will need to seek the services of a suitable qualified lawyer. In the first instance you might wish to contact our colleagues at JISC Legal.

Introduction

This paper aims to provide some basic information and food-for-thought surrounding the increasingly popular uses of digital time-based media, especially its use within education; however, much of the information is applicable to the cultural heritage sector. This paper is not intended as a definitive standard, but aims to disentagle and explain some of the complex and often confusing information regarding rights and media in a readable and accessible format. It should also be noted that the content does not constitute actual legal advice, and if any of the information within this paper leads to further questions regarding your own institution’s projects, then please do not hesitate to contact us via our helpdesk, or our sister service JISC Legal for further assistance.

The rising use of digital time-based media in institutions has been in parallel with the technologies available to create such resources, and the means to deliver and access them. The flip side of this is that every media resource, however large or small, old or new, has associated rights that need to be taken into account in order to protect people’s work and, comply with the law. Furthermore, the role of ethical practice needs to be taken into account to prevent information and resources being used in inappropriate contexts.

1. Introduction to rights and time-based media

Every physical resource has associated copyrights, put simply, to protect the copying of a piece of work. With time-based media a production is likely to involve the performance of individuals, therefore an added dimension, performing rights, are needed to protect the specific performance of the work. The work can be performed by others, but showing or copying your performance of the work is protected. These performance rights are independent of copyright, but should be treated in a similar way. Section 3 of this paper discusses all of the rights associated with recording individuals.

It is increasingly common for time-based media productions to consist of a wide range of different media sources. Access to resources via the web and more powerful technologies is slowly moving audio and video production away from conteent determined by the teacher, such as traditional talking heads towards richer sources of content creation. Presentation slides, images, film or sound materials from other sources and even internet pages and blogs can be embedded into productions. Materials from any of these sources (and others) have their own associated rights that need to be taken into account independently from your production as a whole. These issues are discussed further in section 4.

An important by-product of implementing a progressive rights policy is the effect on students and users. For example, with the increase of student generated media in education, dissemination of copyright information is crucial to promote good practice and awareness in an area where ignorance can be in direct breach of the law. Attention to good practice also brings direct benefits to their academic and professional development.

2. What’s the use?

Copyright law is in place to protect the rights of those involved in producing work. Although it can be difficult to understand at times it is important to protect the works produced by your institution, and to provide protection against unlawful exploitation of work produced by people beyond the institution, whether this is intentional or not.

Before a production project begins it is important to ascertain how you intend the materials to be used, not just in the short-term, but the possible ways in which they may be delivered, accessed and used in the future. Planning these potential avenues of use will help to make sure that you collate all of the relevant permissions and rights involved for the appropriate uses, saving you time and more importantly avoiding any potential legal disputes in the future.

3. Recording people

What rights exist when people are being recorded?

1. Copyright of content - The creator of the work owns the literary copyright of the work. For example, the writer of the script or the author of an extract of a book being read own the copyright of each respected work.
2. Recording rights - These are owned by the person (or people) who make the recording. They can be sometimes referred to as the producer or the recordist - the person physically manning the recording equipment.
3. Performance rights - The literal interpretation of the script (or content) is owned by the person(s) being recorded and reading (or acting) it out. This also has associated copying rights which can, for example, restrict students making copies for themselves. Performance rights and recordists rights, when not waived, exist for 50 years from the year they were made.
4. Moral rights - The moral (or artistic) rights of a piece of work exist to identify the author with his or her work, and to ensure that it’s integrity is not lost. They lie solely with the author of the work and cannot be reassigned, or traded in any way. That said, moral rights can be waived, and in doing so they allow users the right to edit or amend the material.

To adhere to moral rights:

• The author should be identified within the production.
• You are prohibited from playing a version of the work which has been modified, if the modification may be damaging to the author.

4. Who automatically owns what rights?

The Copyright, Designs and Patents Act 1988 (CPDA) specifies that any copyrights associated to a literary, dramatic work, sound recording or film made by an employee during the course of their employment, is automatically owned by the employer, unless otherwise agreed. However, performance rights and copyrights created outside employment, and those of non-employees will need to be attained.

Make sure the individuals you are recording are happy with the ways that you intend to use the resource (see Section 2). Verbal consent of this will indicate a person’s permission at a given time, though will not affect their rights to amend this decision at a later date.

In education, this piece of law is often reiterated in an employee’s contract, unless it is otherwise negotiated prior to employment. Academic researchers in institutions are often faced with difficulties understanding the rights associated with their work, especially when they move between institutional employment. For further information The British Academy and the Publishers Association have published the very informative paper - Joint Guidelines on Copyright and Academic Research - Guidelines for researchers and publishers in the Humanities and Social Sciences, which addresses issues such as this.

If your project involves outsourcing work to external contractors, such as a media production company, they will automatically own the rights associated with the making of the resources. A contract will therefore need to be signed, to avoid the company having dictatorial powers in the future regarding the use of the resources.

5. Attaining rights and clearance forms

A copyright clearance form allows an individual to pass over their rights to you (or in nearly all cases, your institution). This is based on the conditions set against their signature which is why it is important to plan ahead. The potential uses and means of delivery need to be expressed clearly in the clearance form. This should give the producer adequate permissions while protecting the rights of the person being recorded.

Commonly, a clearance form will state that the signatory signs away all their associated rights to a piece of work. This can allow for a generic clearance form to be used in all circumstances, negating the need to be specific about individual rights, which may or may not change during the course of the production.

Further information on the clearance process can be found in this excellent online guide, The Copyright Toolkit.

An example of a copyright clearance form (PDF) can be seen here.

NOTE: It is advised that you seek legal advice via your institution when it comes to creating clearance forms.

6. Using third party materials

If you intend to include works that have been created where you or your institution are not the copyright holder, then you must obtain the appropriate permissions from the rights holder. Examples include images in a slide presentation that were downloaded from the internet or commercial music being played during a recorded lecture.

Commercial works, such as songs or videos often have rights where ownership can be very difficult to establish and permissions impossible to obtain. Care should be taken when selecting and including any third party material.

For more information on using music and sound effects see section 7.

7. Adding music/sound effects

Sourcing free-to-use sounds to use in your productions can be a rather time consuming and often problematic task. Creating your own audio for sound effects, idents, background music or intro’s may be beyond the scope of your project, and finding sound files online where the permissions can be concretely determined is often very difficult.

JISC Digital Media will soon be delivering an online tutorial on finding free-to-use sounds. You may also find our forthcoming documents Creating an Audio Ident, and Finding Video, Audio and Images Online contain helpful information.

8. Ethics and libellous content

Whereas this paper does not wish to go into any great detail regarding the ethical issues relating to the way that recordings of people are made and used, an awareness about ethics is important. Ethical guidance relating to recordings in time-based media should be in-line with institutional policies and requires that it is of paramount importance that the producer acts responsibly, treating subjects with care and respect.

As expected, if you publish a work which contains any libellous content, then legal responsibility lies with your institution. However, if, for example, an employee acts in a manner outside of the normal conduct authorised by your institution, then liability lies with the individual.

The best way of minimising the delivery and exposure to libellous content is by maintaining as much control as possible over the content being created and/or delivered. This is especially crucial for occasions when staff members or students are encouraged to produce and upload their own content.

When producing your own media, the following questions may help you identify any areas where decisions need to be made when making your resources available to your audience.

Ethical Checklist

• Have you fully explained how you intend to use the resource with those who are portrayed or perform?
• Are there any areas where people you are recording can be deemed as vulnerable? Areas such as detailing personal experiences or discussing sensitive issues?
• Are there any views or opinions expressed which may later reflect badly on the person speaking or that may may be deemed as offensive?
• Does any content intend to discredit or diminish the works of others?

The above list of questions is intended to provoke thought and is by no means extensive. Also many cases require a judgement to be made as often there is no clear ‘right or wrong’ solution. In some cases the producer should protect themselves by stating that the views belong to those of the individual and not of the producer or producer’s institution

More detailed information on liability (specifically liability with regard to Podcasts) can be found in the JISC Legal document - Podcasts and the Law (PDF).

9. Managing your rights information

The inclusion of ascertaining rights into a production workflow can not only save time and resources in the short term, but can alleviate any issues which may arise later on where rights have not been fully sought, or if they are challenged or withheld by a party.

As well as completing the appropriate clearance forms (see section 3), the obtaining of rights for third party works should be assessed and documented (with dates) prior to and during production. This log should be actively maintained by the appropriate members of staff and backed up regularly.

For more information on workflows and rights the JISC funded Web2Rights project has some excellent guides, specifically their flowcharts.

10. Delivering your media

There are many ways of licensing your productions for delivery either via physical distribution or the web. Institutional policy, and/or the objectives of your project may dictate how this will be done, and your first port of call should be with your institution’s legal department.

Using Creative Commons licensing is one very popular method of protecting resources as it allows you to tailor the restrictions and privileges given to your audience, in a very simple way. For example, it can permit any use of a resource as long as it is correctly attributed, or it can reserve all rights of the resource making it viewable only (i.e. no copying or further use is allowed).

References and useful links

• Stutter, G & Gibson, Dr. J (2007) Podcasts and the Law. JISC Legal
• The Copyright Toolkit (2007)
• The Steeple Podcasting Booklet (2009)
• Copyright, Designs and Patents Act (1998) c.48
• The Web2Rights Project (JISC)
• Creative Commons

Last updated: 17 February 2010
Published in: Managing a project | Creating new digital media
Tags: copyright | digital collections | digital preservation | digital preservation policy | moral rights | performance rights | podcasts | recording rights | screen capture | sound recordings | video | workflow

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Asset Management: Papermule DAM & Workflow Engine

Last updated: 16 February 2010
Published in: Managing your digital resources
Tags: delivery | digital collections | software

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Summary

JISC Digital Media has surveyed a range of image management software developers to gather specific information about their systems. These are the responses from Papermule DAM & Workflow Engine.

Please note: The following information has been provided by the system developer/vendor in answer to a detailed survey carried out by JISC Digital Media, but has not been independently verified. It is provided to help you identify systems to evaluate in more detail, but you are advised to check with the system developer/vendor to see if the system has changed or there are later versions available.

There are a wide range of different image management systems available. To help identify those most suitable, we would recommend you also look at our introductory papers on Systems for Managing Digital Media Collections and Choosing a System for Managing your Image Collection.

To compare this system’s features with those of others, please see the full list of systems who have responded to our survey on the Image Management Software page.

Information supplied: February 2010

Papermule DAM & Workflow Engine www.papermule.co.uk
We asked the system developer to use 50-100 words to sum up and promote their system to a very broad audience: The team at Papermule have spent the last 20 years providing digital asset management and workflow solutions to many well known businesses (The Telegraph, The Guardian, Associated Newspapers, Future Publishing, National Magazines, Yellow Pages, Thomson Directories, Cambridge University Press to name a few in the UK). We specialise in customized solutions and have an enterprise level DAM offering that can be easily configured to meet each client’s individual requirements. 100% WEB based with a variety of interfaces to suite particular users the solution can be installed locally or hosted remotely either way ensuing your assets are managed safely and securely.
Current version	1.7.1
Current version released	December 2009
Next version due (approx)	March 2010
Main sectors aimed at	Corporate or professional (private sector); Government (public sector); Further or Higher (Tertiary) education; Charitable/not-for-profit; Newspaper, Magazines, Directories, Catalogues
Main users aimed at	Professional photographers; Picture Library staff; Creative staff (e.g. illustrators, designers); Marketing staff; Records Managers; Librarians; Archivists; Museum/Gallery professionals
Type of system		Folder viewer/image browser
		Web gallery system
		Image/photo management system
		Digital asset management system (DAM)
		Musem/gallery/library/achive collection management system
		Virtual learning environment (VLE)
		Content management system (CMS)
		Digital repository system
		Digital library system
		Other: Workflow automation and communication
Open-source/Proprietary?	Proprietary but incorporates open/standard technologies
Complexity	Customised system - vendor builds from standard modules according to user’s requirements
Maximum size of the catalogue (e.g. number of records or filesize)	Near limitless - hardware and RDMBs bound
Handling of images
Image- object- or workflow-centric?	Asset centric with project/collections and workflow
Adding images to system		Captures images directly from a scanner from within the system
		Captures images directly from a tethered camera from within the system
		‘Drag and drop’ into system
		Scans a computer for new images
		Scans external drives/memory devices for new images
		Scans network servers for new images
		Sets up automatically ‘watched’ folders
		Keeps system and folders in ‘sync’
		Other: e-mail requests and processing
File formats supported		RAW formats
		DNG
		TIFF
		JPEG
		GIF
		PNG
		JPEG2000
		PSD
		PDF
		EPS
		Flash
		SVG
		Audio formats
		Video formats
Where can images be located?	Must be held within the system itself or a designated folder/location
Image management		Ability to manage original image files (e.g. move, copy, rename or delete) from within the system
		Ability to organise images into virtual ‘folders’, ‘galleries’ or ‘categories’ to aid management and retrieval
		Image versioning
		Rating system (e.g. star or numbers for best images)
		Automatic generation of thumbnails and preview images
		Ability to zoom image to 100% (full size) within data entry interface
Image editing provision	Basic editing within system + check out/in to dtp apps for advanced editing
	Configurable option for whether edits are made to originals or copies
Specific image editing functions		Resizing
		Rotating
		Cropping
		Sharpening
		Red-eye removal
		Dust/noise removal
		Brightness and contrast adjustments
		Levels adjustments
		Curves adjustments
		Support for ICC colour management
		Creative filters
Other significant editing functions
Print templates
Auditing of who did what/when to image
Other image-related features
Handling of metadata
Metadata structure	Relational database structure
Customising fields		Add new catalogue fields
		Delete catalogue fields
		Hide catalogue fields from data entry interface
		Re-label catalogue fields
		Re-order catalogue fields
Time saving features		Set up templates or defaults
		Clone or duplicate records
		Automatically catalogue images upon import
		Batch edit metadata
		Global find and replace
Controlled vocabularies		Create drop-down pick-lists
		Support for theasauri (with broader and narrower terms)
Spell-checking/validation		Spell-checking
		Validation of terminology
		Validation of dates and numbers
Support for UNICODE (non-Latin characters)
Importing		Import existing metadata in standard delimited formats
		Import existing metadata in XML formats
Exporting		Export of metadata in standard delimited formats
		Export of metadata in XML formats
Metadata interoperability (e.g. metadata harvesting, cross-searching)		Automatic exposure of metadata as OAI-PMH data
		Support for Z39.50 searching
		Support for search scripts
Embedded metadata support		Read IPTC metadata from within the image file
		Read EXIF metadata from within the image file
		Read XMP data
		Read other metadata from within the image file
		Write IPTC metadata into image file
		Edit EXIF metadata
		Write XMP data
		Write other metadata
Data-entry interface		Client-based/program-based data entry interface
		Web browser-based data entry interface
Reporting/auditing		Auditing of who did what and when to the metadata
		Editable templates or scripts for generating reports
Other metadata-related features
Delivery to users
Web browser-based end-user interface
Customisability of interface		System manager can customise interface
		End-user can customise their view of interface
Publishing of images		Publish as static gallery to Web
		Publish as dynamic searchable Web catalogue
		Publish to CD-ROM
		Email images from system
Search/browse features		Browse collection by categories
		Search the collection
		Search via thesaurus
		Advanced search features (e.g. Boolean logic, wildcard or ‘sounds like’ searching)
		Content-based image retrieval (CBIR)
Zooming functionality
User interaction		Users can ‘bookmark’ or store images
		Users can annotate bookmarked images
		Users can upload their own images to the system
		Users can create slide shows
Security/Digital Rights Management (DRM)		Access control based on roles or profiles
		Access control based on individual usernames and passwords
		Compatibility with standard educational authentication services (e.g. Athens or Shibboleth)
		Built-in Digital Rights Management technology (e.g. watermarking)
Interoperability/interaction with other systems
Other significant delivery functionality
Company and support information
Country in which system developers are based	UK
Approximately how many UK users are there?	90
UK office, representative or primary reseller	Papermule Ltd Units 16/17 Diss Business Centre Diss Norfolk IP21 4HD
Independent user-group for this system?
UK-based training available?		Training is delivered on a train the trainer of key user basis and is costed based on a daily rate
System support		24/7/365 support is available. The support cost is based on hours covered and initial system cost
Other services available		Papermule Ltd provide a consultancy service along with bespoke development and migration services.

Please note: The above information has been provided by the system developer/vendor in answer to a detailed survey carried out by JISC Digital Media, but has not been independently verified. It is provided to help you identify systems to evaluate in more detail, but you are advised to check with the system developer/vendor to see if the system has changed or there are later versions available.

There are a wide range of different image management systems available. To help identify those most suitable, we would recommend you also look at our introductory papers on Systems for Managing Digital Media Collections and Choosing a System for Managing your Image Collection.

To compare this system’s features with those of others, please see the full list of systems who have responded to our survey on the Image Management Software page.

Last updated: 16 February 2010
Published in: Managing your digital resources
Tags: delivery | digital collections | software

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Audiovisual Copyright: Frequently Asked Questions

Last updated: 03 February 2010
Published in: Managing your digital resources | Finding and using digital media
Tags: copyright

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Summary

By reviewing copyright enquiries which have reached us via our helpdesk, we’ve collated answers to some of the most common. These are presented here as an FAQ (Frequently Asked Questions).

Please note: The remit of JISC Digital Media includes the provision of practical advice and guidance to the FE and HE communities on copyright matters. Staff at JISC Digital Media are not lawyers and all advice is provided on that basis. Should you wish to receive a legal opinion in relation to a copyright matter then you will need to seek the services of a suitable qualified lawyer. In the first instance you might wish to contact our colleagues at JISC Legal

Although we can provide general principles, each case will be different and different considerations will apply. Readers are encouraged to contact us directly with any queries which may arise. Please also note that we cannot provide legal advice, this FAQ is intended simply as a guide to good practice in the areas of copyright and intellectual property rights (IPR).

Can I use material from TV/radio for teaching purposes within my institution?

Section 35 of the Copyright, Designs and Patents Act 1988 entitles educational establishments to make off-air recordings of broadcasts to use for educational purposes. However, the Act also entitles rights-owners to obtain payment from educational establishments for use of their material, but only under an approved licensing scheme.

The Educational Recording Agency (ERA) licence has been in effect since 30th May 1990.  The Licence permits recordings of broadcasts to be made for non-commercial educational use. This includes radio, television and free-view broadcasts, but not pay per view broadcasts.

Key conditions of ERA include

• Recordings must not be edited or modified (though extracts may be recorded)
• Recordings must be marked with the date of the broadcast, the title of the recording, the name of the broadcaster, and the following statement: This recording is to be used only for educational and non-commercial purposes under the terms of the ERA Licence
• Details of any recordings made must be kept by the relevant department within a participating institution
• Recordings made under the ERA Licence may be communicated to registered students within the premises of an educational establishment. This means that recordings made under the ERA Licence may, for instance, be digitised and stored on a VLE, providing all access to that VLE is carried out whilst on campus (the digitised recording must also bear the statement given above). Off-campus access in not permitted under this licence.
• Does not cover Open University programming (see below)
• Does not cover recordings bought commercially
• Does not cover foreign, satellite and cable programmes, ‘On demand’, and interactive services
• Generally does not cover internet transmissions

The Open University Licensed Off-Air Recording Scheme covers both TV and radio broadcasts made by the Open University. It allows recordings of OU broadcasts to be retained by the University for educational purposes and up to 4 copies of each recording to be made.

Main conditions of the Open University Off-Air recording licence include

• Recordings must be labelled with the title of the programme and the date upon which it was recorded
• Recordings may be loaned to students providing there is no charge for loaning the recordings
• Recordings may be digitised and stored on a VLE for on-campus access only (no off-campus access permitted)
• It does not allow the incorporation of any OU recorded material into other audio-visual or electronic productions
• Or digitised recordings stored on the VLE may not be accessed off-campus.

So how can I use materials from TV/radio for teaching purposes off-campus via my VLE?

Since 1 August 2007 ERA has offered its licensees the opportunity to take out an additional licence which will enable licensed ERA Recordings to be accessed by students and teachers on line whether they are on the premises of their school, college or university, or at home or working elsewhere within the UK.

Licensees will be required to have in place procedures to ensure that only “Authorised Users” will be able to gain access to ERA Recordings stored on the servers of a licensed establishment. The recordings cannot be posted for open access by people who are not Authorised Users or for any purposes other than educational use. It is expected that a similar add-on licence will be announced by the Open University in due course.

Can I make use of this movie, album or other commercially available media for teaching purposes within my institution?

Recorded or live music can be freely played for educational purposes if the audience is just made up of students and teachers. Educational establishments may play or show a sound recording, film, video, DVD, broadcast or cable programme to audiences of staff and students “in the activities of the establishment or for the purposes of instruction”. Labels on videos such as “licensed for home use only” may be ignored if the audience is only made up of students. No charge must be made. If members of the public are admitted then a licence would have to be given by the copyright holders. Note that there is no automatically granted permission to media shift (for instance rip a CD to MP3) in UK law.

I want to use a commercial song or video in a Podcast that I wish to make available via the web. Am I allowed to do this?

If you intend to include works that have been created where you, or your institution are not the copyright holder then you must obtain the appropriate permissions from the rights offer.
Commercial works, such as songs or videos often have rights that can be very difficult or even impossible to obtain so care should be taken when selecting any third party material.

Where can I find music online to include in my productions that doesn’t infringe copyright?

There are numerous websites that provide free and/or paid music online which have little or no rights restrictions associated. Music hosting sites with the emphasis on user generated content can contain a diverse catalogue of music and sounds and many ask their users to waive all copyrights on upload which allows anyone to use the files. Music which has been licensed under Creative Commons may also be suitable for your needs (although types of license can vary).

Our advice paper Links to Video, Image and Audio Resources links to a number of sites that host free to use music and sound effects.

How can I protect media files I’ve created from unauthorised use and copying?

There are many ways to protect the material you have made yourself. Digital Rights Management can be used to ensure only your authorised audience can play back the material. DRM does risk antagonising your intended audience especially at times of hardware or software updating.  Some DRM measures are so stringent (for instance time limited licensing) that accessibility can be severely limited. Many online collections have abandoned DRM in favour of streaming formats which cannot easily be downloaded to a local machine.

By far the most popular method of copyright protection is a clearly displayed statement, spelling out permissions. Creative Commons is a public realm licensing scheme which gives content creators a multi-layered set of options ranging from open reuse which simply requires the creator to be credited to clear stipulations of just how the content should be reused.

I want to make a recording in a public place, whose permission do I need?

Firstly, be aware that a ‘public place’ isn’t a simple defined term. Shopping centres are not deemed public places in this context and permissions will need to be sought from the overarching management. Similarly ‘public’ parks are owned and managed by borough councils and technically speaking permissions should be sought to record there. This is unlikely to be an issue though, unless large groups of media students regularly descend, and disturb the peace. Generally photographing buildings is permitted for non-commercial purposes.

Making recordings of members of the public is permissible as long as they are not ‘harassed’. The law is not concerned with the making of the media, only with their publication. If recordings are subsequently made public then the subject of the media has recourse to the civil law, and permissions are required.

Permission from a parent or guardian should be sought before taking any recordings of children or minors.

My legacy media collection is falling apart before my eyes. Can I copy the content in order to preserve it?

There is still no exception in UK law for preservation copying. For materials which are still in copyright, permissions should be sought from copyright holders prior to any copying being done. This area is under consideration though with museums, libraries and archives lobbying for change.

My video collection has no closed captions or audio description and this is limiting its use. Can I add some?

Unless you are the copyright owner for a video you will need permission to add interpretive text or descriptions. Off air licensing schemes such as ERA expressly forbid the third party adding of interpretive information.

Can I use this media I found on a social networking site for teaching purposes within my VLE?

Careful investigation of media found online should be made before it is made available publicly. Even if permission seems to have been granted through Creative Commons, the question should be asked: ‘Did the poster have those permissions to grant?’ Take a look at other posts made by the same individual, do they seem incongruous or maybe to good to be true? If in doubt, search for similar media made freely available by more reputable sources such as JISC Collections, Teachers TV or Teachertube.

I want to commission a media production company to make a recording for my institution. Will I own the copyright?

Not unless the institution was named as the copyright holder in a contact sign by the media producers. By default the initial copyright would be owned by the creator of the media, not its commissioner.  Unless such a contract is signed, the media producers would be able to dictate terms of usage to the commissioning institution.

Unlike copyright, artistic or moral right rights (the right to be credited as the creator of a work for instance) cannot be transferred or sold and are always retained by the creator of the work.

I would like to record my students during lectures and meetings. Is it ok to publish this material if they verbally agree at the time?

Yes it is ok, but to be on the safe side, you should communicate exactly what you intend to do with the material and obtain written (signatory or electronic) permission to that effect from your students, especially if you are planning to do a lot of this. This will make sure that your students understand your intentions and can express any reservations right away to prevent any future challenges having an effect on publishing your resources, where no waiving of rights can be physically proven. You should also be very careful to address any content that might be inappropriate to publish, before making the recordings accessible.

A copyright clearance form will provide your institution with the appropriate permissions. Please see this example of a copyright clearance form (PDF).

My students have produced some of their own recordings that include some rather critical accounts of public figures and academic works. As we are an educational establishment, is it fine to make these publicly available?

Educational or not, content that includes defamatory or libellous comments should not be made publicly available for fear of legal action. Regardless of the individual making these comments, your institution will also be liable for publishing the materials. For information relating to your specific situation, it is advisable to seek legal advice via your institution.

Last updated: 03 February 2010
Published in: Managing your digital resources | Finding and using digital media
Tags: copyright

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Copyright: An Overview

Last updated: 03 February 2010
Published in: Managing your digital resources | Finding and using digital media
Tags: copyright

Comments (1)

Summary

Copyright and other intellectual property rights are central to the development, use and sustainability of digital collections. This advice document provides a broad overview of copyright.

Contents

1. What is copyright and what does it protect?

2. Duration of copyright

   • 2.1 For literary, dramatic, musical or artistic works
   • 2.2 For sound recordings
   • 2.3 For films
   • 2.4 For broadcasts
   • 2.5 For typographical arrangements of published editions
   • 2.6 Quick reference guide to the duration of copyright

3. Fair dealing - acceptable use of copyrighted materials

   • 3.1 Making temporary copies
   • 3.2 Research and private study
   • 3.3 Criticism and review
   • 3.4 Incidental inclusion of copyright material
   • 3.5 Instruction or examination
     

4. Other types of intellectual property rights

   • 4.1 Moral rights
   • 4.2 Performance rights

Please note: The remit of JISC Digital Media includes the provision of practical advice and guidance to the FE and HE communities on copyright matters. Staff at JISC Digital Media are not lawyers and all advice is provided on that basis. Should you wish to receive a legal opinion in relation to a copyright matter then you will need to seek the services of a suitable qualified lawyer. In the first instance you might wish to contact our colleagues at JISC Legal.

1. What is copyright?

Copyright, together with moral rights, patents, trademarks, database rights, design rights and performers’ rights form part of the family of Intellectual property rights (IPR), which is the name of the broad range of rights that protect the fruits of human innovation, creation and invention. The Intellectual Property Office (formerly Patent Office) has the responsibility for managing how IPRs are administered in the UK. Information about the other forms of IPR can be found at the Intellectual Property Office website.

In the UK, copyright is an automatic right afforded to creators of literary, dramatic, musical and artistic works giving the creators exclusive economic rights to control copying, adaptation, issuance of copies to the public, performance and broadcasting of the work that they create. In return for licensing their material creators are entitled to receive royalties. In the UK, copyright is only afforded to certain classes of work: these must be tangible or fixed is some kind of material form. Ideas cannot be given copyright protection.

Other conditions that need to be met for protection under UK copyright law include that:

The work must be original, which means that it must not have been copied from something that already exists. This is complex and not always straight forward when applied to digital media. Whilst simply scanning a photograph with little human intervention is unlikely to be classed as original, an image that is scanned, altered and enhanced using a high level of human skill and judgement in order to achieve the effect of the original work might in itself be afforded copyright protection. It is important to note that sound recordings, films, broadcasts and typographic works do not need to demonstrate originality in order to be protected by copyright.

The author must be a qualified person - a British subject or someone who normally lives or is domiciled here, or the material must first be published in this country (note that protection is extended to work created in other countries or by other nationalities under International Copyright law).

Because copyright protection is automatic and does not need registration, much digital content found on the Internet will be protected by copyright. In most cases, the copyright holder will need to be approached prior to any use of the digital resource(s) that fall beyond the limited exceptions permitted by law. This also means that although a copyright credit line is not necessary for a work to be afforded copyright protection, if a credit line is used, its use can provide proof that the work is protected by copyright particularly in the context of international publishing activities that the Web provides. If used, the copyright credit line should take the following form:

“Year, name of rights holder, All Rights Reserved”.

Increasingly, digital content is being made available under open content licences such as Creative Commons Licenses. These provide creators with the ability to pre-determine the terms of use of their digital creations, providing other users the ability to use the digital resources without having first to contact the rights holder.

You can access further information about licensing content from the Joint Information Systems Committee (JISC) and from the JISC Advance advisory body JISC Legal.

2. Duration of copyright

Before deciding on whether you are allowed to make an original work available digitally you will need to ascertain whether or not copyright applies or whether it has lapsed. The Copyright, Designs and Patents Act 1988 states that the duration of copyright is as follows:

2.1 For literary, dramatic, musical or artistic works

Copyright expires at the end of 70 years from the end of the calendar year in which the author dies subject to the following:

If the work is of unknown authorship copyright expires either at the end of the period of 70 years from the end of the calendar year in which the work was made, or if during that period the work is made available to the public, at the end of the period of 70 years from the end of the calendar year in which first made available.

That said, should the identity of the author become known before the end of the period outlined above then copyright will expire at the end of the period of 70 years from the end of the calendar year in which the author dies.

2.2 For sound recordings

Copyright expires at the end of the period of 50 years from the end of the calendar year in which the recording is made, or if during that period the recording is published, 50 years from the end of the calendar year in which it is first published, or if during that period the recording is not published but is made available to the public by being played in public or communicated to the public, 50 years from the end of the calendar year in which it is first made available.

That said, where the author of a sound recording is not an national of an European Economic Area (EEA) state, the duration of copyright is that to which the sound recording is entitled in the country of which the author is a national, provided that does not exceed the 50 year periods outlined above.  Moreover, the duration of copyright will need to be considered in line with the international obligation to which the United Kingdom became subject prior to 29 October 1993 (European Council Directive 93/98/EEC of 29th October 1993).

2.3 For films

Copyright expires at the end of the period of 70 years from the end of the calendar year in which the death occurs of the last to die of the following persons:

a. The principle director
b. The author of the screenplay
c. The author of the dialogue
d. The composer of music specially created for and used in the film

However, if the identity of one or more of the persons referred to above is known yet the identity of one or more of the others is not, the reference to the death of the last of them to die shall be construed as a reference to the death of the last whose identity is known.

Moreover, if the identity of all the persons listed above is unknown then copyright expires at the end of the period of 70 years from the end of the calendar year in which the film was made, or if during that period the film is made available to the public, at the end of the period of 70 years from the end of the calendar year it was first made available.

Where the country of origin is an EEA state and the author of the film is not a national of an EEA state, the duration of copyright is that to which the work is entitled in the country of origin.

2.4 For broadcasts

Copyright in a broadcast expires at the end of the period of 50 years from the end of the calendar year in which the broadcast was made subject to the following:

Where the author of the broadcast is not a national of an EEA state, the duration of copyright in the broadcast is that to which it is entitled in the county of which the author is a national (provided it does not exceed the 50 year limit descried above).

It should also be noted that copyright in a repeat broadcast expires at the same time as the copyright in the original broadcast.

2.5 For typographical arrangement of published editions

Copyright in the typographical arrangement of a published edition expires at the end of the period of 25 years from the end of the calendar year in which the edition was first published.

2.6 Quick reference guide to duration of copyright

The following gives a brief overview of copyright duration for a number of works. Please refer to the Act for comprehensive information.

3. Fair dealing - acceptable use of copyrighted materials

The owner of the copyright in a particular work or works has the exclusive rights to the following acts in the United Kingdom:

a. To copy the work
b. To issue copies of the work to the public
c. To rent of lend the work to the public
d. To perform, show or play the work in public
e. To communicate the work to the public
f. To make an adaptation of the work or do any of the above in relation to an adaptation

That said copyrighted material can be used in a number of ways whereby copyright is not infringed.

The following is a description of some of the ways in which copyrighted materials can be used without infringing the copyright. It is stressed that this is not an exhaustive list.  For a full list please refer to the Copyright, Design and Patent Act 1988.

3.1 Making temporary copies

The making of temporary copies of copyrighted works which is transient or incidental and which are not produced for economic gain do not infringe copyright. The types of work included are literary, dramatic, musical or artistic works, the typographical arrangement of a published edition, a sound recording or a film. Making temporary copies does not apply to computer programs or databases.

3.2 Research and private study

Fair dealing with a literary, dramatic, musical or artistic work for the purposes of research for non-commercial purposes does not infringe any copyright in the work as long a an appropriate acknowledge is also included.

3.3 Criticism and review

Fair dealing with a work for the purpose of criticism or review does not infringe any copyright in the work provided that an appropriate acknowledgement is included (and provided that the work has been made available to the public).  For the purposes of the Act a work has been made available to the public by any means if one or more of the following have been undertaken:

a. Copies of the work have been issued to the public
b. The work has been made available by means of an electronic retrieval system
c. Copies of the work have been lent to or rented to the public
d. The work has been performed, exhibited, played or showed in public
e. The work has been communicated to the public

3.4 Incidental inclusion of copyright material

Copyright is not infringed if a work is included incidentally in an artistic work, sound recording, film or broadcast. Moreover, copyright is not infringed if such incidental material is issued to the public in the form of copies of the material or the playing or showing of the material to the public.

3.5 Instruction or examination

Copyright in a literary, dramatic, musical or artistic work is not infringed by its being copied in the course of instruction or of preparation for instruction provided the copying is undertaken in line with the following:

a. It is done by a person giving or receiving the instruction
b. It is not done by means of a reprographic process - for the purposes of the Act a “reprographic process” is defined as making facsimile copies, or involving the use of an appliance for making multiple copies.  This includes work held in electronic form, any copying by electronic means but does not include the making of a film or sound recording.
c. Sufficient acknowledgment accompanies any copy   - for the purposes of the Act “sufficient acknowledgement” means an acknowledgement identifying the work in question by its title (or other description) and identifying the author unless in the case of a published work it is published anonymously, or in the case of an unpublished work, it is not possible to ascertain the identity of the author by a reasonable enquiry.
d. The relevant instruction is undertaken on a non-commercial basis

Copyright in a sound recording, film or broadcast is not infringed by its being copied by making a film or film sound track for the purpose of instruction provided the copying is undertaken by the person giving or receiving the instruction and that an acknowledgement accompanies the copy.

Copyright in a literary, dramatic, musical or artistic work which has been made available to the public is not infringed by its being copied in the course of instruction if the following apply:

a. The copy is done by a person giving or receiving the instruction
b. The copying is not done by means of a reprographic process
c. That sufficient acknowledgement is given to the copy
d. That the copying is undertaken in line with fair dealing

It should also be noted that copyright is not infringed by anything done for the purposes of an examination as long as an appropriate acknowledgement is given and where the copying is done to set the questions, communicate the questions to the candidates or by candidates answering the question.

4. Other types of intellectual property rights

As was stated earlier copyright is but one aspect of intellectual property rights. I should like to look at two other rights that are closely aligned to, but different from copyright. They are Moral Rights and Performance Rights.

4.1 Moral rights

As well as the economic benefits of copyright afforded to a creator of a work, the Copyright, Designs and Patents Act 1988, implemented from 1st August 1989, introduced the concept of ‘Moral Rights’ which are distinct and separate from property rights. They provide the creator with the ability to protect the artistic integrity of their work. Moral rights can be summarised as follows:

1. The right of the author of a work to be acknowledged as the author or creator
2. The right of the author to object to false attribution
3. The right not to have his or her work subjected to ‘derogatory’ treatment

In addition to the above there is the additional moral right afforded to the subjects of still images and moving images taken for domestic and private purposes. This restricts the subsequent use of such images beyond the purposes for which they were originally taken, without the consent of the subjects.

In the digital environment, Moral Rights are important because of the ease with which content can be shared, altered and manipulated. Creators of digital resources should be credited appropriately and measures undertaken to ensure provenance information about digital surrogates is not lost in the process of digitisation.

It should also be noted that, unlike copyright, Moral Rights cannot be transferred: but they can be waived. Moreover, ordinarily Moral Rights do not arise in work produced by staff during the course of their employment.

More information about moral rights can be found at the Intellectual Property Office.

4.2 Performance rights

Performance rights apply world wide to literary, musical and dramatic works. Under UK legislation (the Copyright, Designs and Patents Act 1988) there is no requirement to register the right. Performance rights are separate from copyright with each participant in a performance entitled to a claim of the right.

The Act defines a “performance” as:

1. A dramatic performance
2. A musical performance
3. A reading or recitation of a literary work
4. A performance of a variety act or similar performance

The natural owner of the right is the relevant performer or performers. The rights granted under the act are the reproduction right, the distribution right, rental and lending rights and the making available right.  The performance right s can be sold or licensed but any arrangement to do so must be done in writing.

The duration of a performer’s right lasts 50 years from the date of the recording. If the recording is first published or shown in public within that initial term, protection of the right continues for another 50 years. The performance right also entitles the performer to be remunerated for any performance communicated to the public. The collection of any payment due might be assigned to a third party collection agency which will collect payment on behalf of the performer.

Any right to reproduce performances is infringed when a person records, broadcasts, or copies a recording or broadcast of a whole or substantial part of a qualifying live performance.

Further information on performance rights and related topics can be found at the Copyright Licensing Agency.

Last updated: 03 February 2010
Published in: Managing your digital resources | Finding and using digital media
Tags: copyright

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Analogue Film Types Used for Still and Moving images

Last updated: 27 January 2010
Published in: Digitising analogue media | Creating new digital media
Tags: analogue collections | digitisation | negatives | photographs | restoration | scanning

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Summary

This document looks at the history of photographic and movie film and how and why the film type has altered over time. The document also contains some frequently asked questions on film types and handling.

Introduction

In the early days of photography, solid materials such as glass plates were used to support the light sensitive emulsion. While glass plates offered high quality they were expensive to produce, fragile, heavy and not very portable. There was a widespread demand for a flexible lightweight film base which could be transported rapidly through a stills or film camera or projector to replace the heavier materials used up to this date.

Cellulose nitrate film provided a flexible transparent substrate onto which the light sensitive emulsion would adhere. It was perfect apart from the fact that it was highly inflammable. Film projectors have to transport the film at speed past a very bright and hot bulb, if the film should jam then it was likely to ignite rapidly and uncontrollably. After a few fatal accidents with nitrate film, projectors and projection rooms had to be modified to contain any fire damage. The projectors had fire traps, which limited the fire to a short length of film. Storage of film beside hot projectors was prohibited and the projection rooms had to be built from solid concrete with metal doors and steel shutters that would close automatically if the temperature in the room got too high.

Nitrate film was used for both still and moving images - while still images were normally kept in open storage, movie films were stored in sealed metal cans. As the film ages, hazardous fumes are released - in open storage the fumes disperse gradually into the environment, however film stored in cans are sealed in with the fumes which further accelerates the decay. As nitrate film degrades it becomes more hazardous and so there is a real urgency to digitise it and permanently remove it from collections.

Even during the height of nitrate film manufacture there was an urgent search for a more stable film base. Cellulose acetate ‘safety’ film was introduced in the early 20th century and while it is much safer than nitrate film it may still degrade under certain conditions. Polyester film may also be referred to as safety film and be marked as such. In the 1950s still photographers started to use polyester film rather than cellulose acetate based material however polyester is difficult to splice together and so it wasn’t until the 1990s that it was adopted by the moving image industry.

We have found some old black and white film negatives in our collection, how can we identify the type of film used?

Nitrate film will normally have NITRATE or the letter N at the edge of the image or alongside the sprocket holes. However some negatives originally captured on acetate safety film were duplicated onto available film, which may have been nitrate and so may have the letter S or SAFETY along the edge though the film is far from safe. The images below show negatives with the manufacturers film type identification printed on the edge.

   
Left, ‘Migrant Mother’ by Dorothea Lange 1936. Right, detail of Lange’s image showing NITRATE. Image has been rotated and flipped to aid viewing. Photo from The Library of Congress on Flickr: The Commons - No known copyright restrictions.

 
Left, James Lynch by Jack Delano 1942. Right, detail of Delano’s image showing SAFETY. Image flipped to aid in viewing. Photo from The Library of Congress on Flickr: The Commons - No known copyright restrictions.

Simple tests can also be used to identify film types. Polyester film can be identified using two polarising filters, one above the other below. It will produce a rainbow colour effect not seen in the other film types. Nitrate film is soluble in methyl alcohol while, acetate and polyester film are insoluble.

We have a collection of still images which includes acetate and nitrate negatives, can we digitise the collection?

First identify the film type and its condition. If the negatives are in a good state then technically you should be able to digitise them. If nitrate film has been positively identified it is recommended that you seek specialist advice on handling, digitising (if safe to do so), storage, or more commonly disposal of the film.

The existence of a nitrate film collection should be brought to the attention of the insurance company otherwise the policy may be rendered invalid and the building and its contents are essentially uninsured.

Nitrate film can spontaneously combust at 49 degrees centigrade so care should be taken to avoid exposing the negatives to heat. Scanners normally use low energy lamps and so are unlikely to generate enough heat to ignite nitrate film though projectors with bright halogen lamps produce significantly more heat.

As cellulose acetate film starts to degrade it releases acetic acid, this then attacks the film releasing more acetic acid, accelerating the process. Eventually the film will become brittle and as the film base shrinks it separates from the image layer and becomes unusable. A vinegar smell is one of the first tell tale signs of deterioration the decay of acetate film is known as ‘vinegar syndrome’. Film showing signs of vinegar syndrome should be separated from the rest of the negatives to contain the damage.

If the decision were made to scan the negatives it would be wise to look at how the scanner digitises film. Some scanners have special film holders, which position the film over the scanning bed, most flatbed scanners press the image down onto the scanning bed. While typical objects can withstand this type of handling it may damage or destroy fragile acetate or nitrate film and so it would be wise to run tests to identify potential risk.

Is our colour film safe?

Colour film regardless of the base layer is prone to fading. Cold storage is the most effective way of slowing or preventing this.

Will our polyester based film degrade?

While the polyester film base is more stable than acetate or nitrate film the emulsion layer may contract over time and potentially detach from the base. If polyester film is tightly bound for extended period it can become difficult to uncurl and risks damage.

We have a large collection of film negatives, they appear to be in good condition and we are unable to digitise them at present, how should we store them in the meantime?

If the collection contains nitrate film (in any condition) then it you should seek specialist advice and contact your insurance company as soon as possible. Some valuable or historically significant nitrate film collections are stored in specialist facilities but this would be prohibitively expensive for most collections.

To slow or prevent deterioration it is essential that all types of film including polyester based stock are kept in a cool dry environment. The minimum requirements vary between film types, colour film which is prone to fading should be kept at 0 degrees centigrade or below and at the lowest possible relative humidity. This should be seen as the optimum conditions for a collection containing black and white and colour film.

If the film is refrigerated it should be stored in sealed containers to avoid contact with condensation. Movie film should be kept in sealed chemically inert containers and stored flat. If stored at room temperature the containers should be vented to allow acetic acid fumes to vent off.

Last updated: 27 January 2010
Published in: Digitising analogue media | Creating new digital media
Tags: analogue collections | digitisation | negatives | photographs | restoration | scanning

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Light Sources for Still and Moving Images

Last updated: 11 January 2010
Published in: Digitising analogue media | Creating new digital media
Tags: digitisation | hardware | lighting | photography | supports and stands | tripod

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Summary

The word photography means drawing with light, without light it is impossible to record a video or still image. So lighting whether in a classroom, office or dedicated photographic studio is an essential component in a photograph or video. The captured image is a record of the light that is emitted, reflected or absorbed by the subject. With a basic understanding of light and how it can be modified the photographer or filmmaker should be able to improve the appearance of their images. This document will look at commonly used light sources and how the user can get the most from them.

Introduction

Light is electromagnetic radiation with a wavelength that is within the visible limits of the human eye. While ultra violet (UV) and infrared (IR) light can be detected by digital sensors and measured by light meters it is beyond normal human perception. Most sensors in digital cameras have IR cut filters mounted on them and some photographers use UV filters in front of the lens to reduce the influence of these non visible (to the human eye) frequencies on the final image. Infra red light can also confuse camera auto focussing systems as it is focussed differently to visible light.

An important quality of visible light is its colour temperature. White light is an equal mix of all of the different visible wavelengths however this combination is often unequal which produces a colour bias. This is known as its colour temperature and is measured in degrees kelvin (K),

Table of common light types and their colour temperatures in degrees Kelvin (K)

White balance controls in digital stills and video cameras are used to identify and correct for the colour bias of different light types.

To create an image whether still or moving a subject has to be illuminated, this could be by; daylight, artificial light such as a domestic household bulb, classroom lighting or specialist photographic lighting such as flash.

The commonly used unit of measure for the intensity of light (not flash) incident on a surface  is lux (lx)

A table of light levels (lux) for common situations

Still and video cameras are designed to deliver good quality results under typical light levels from between 500 lux to over 32000 lux. Under very dark or extremely bright conditions care must be taken to capture useable quality images.

Light Sources

Colour film used for still and moving images is designed to deliver high quality images under specific colour temperatures normally for daylight/flash or tungsten light.  For accurate colour under atypical lighting the analogue photographer or filmmaker normally has to attach colour correction (CC) film or gels over the lights or a CC filter over the lens. Digital stills and video cameras in contrast allow the user to correct for different light types ‘in camera’; this is known as white balancing. Generally speaking this now means that digital photographers and filmmakers are now free to work with most light types without the need for CC filters provided a few steps are taken.

We can divide light sources into two groups, ambient and artificial photographic lighting.

• Ambient is the light present in the scene before the photographer or filmmaker starts work.
• Artificial photographic lighting is light that the photographer or filmmaker introduces to the scene. Ambient and artificial light types can be used separately or combined with care.

Ambient light

Ambient light could be sunlight, moonlight, classroom lighting or domestic lighting etc. As it is the ‘native’ lighting in a scene it will normally give an atmospheric or believable look to an image. If, however, light levels are low, long exposures (using a tripod) or high ISO settings may be required which can prove challenging.

Daylight is the light we are most familiar with and we often try to replicate when we use artificial photographic sources such as flash. Daylight can also be unpredictable and doesn’t always produce the most pleasing illumination but with a little care the photographer or filmmaker can modify and improve the lighting by changing the camera angle, using shade, diffusers or reflectors. Bright sunshine can produce harsh shadows with high contrast, while clouds ‘soften’ the shadows and remove the three-dimensional look.

The colour temperature of daylight can also change; clouds absorb the ‘warmer’ red wavelengths of light which can give the subject a ‘cool’ bluish look. The colour of the light also changes slightly throughout the day; mornings and evenings normally have a ‘warm’ hue while the middle of the day is ‘cooler’. The cameras white balance settings are designed to produce neutral colour under a variety of light sources however, some professional photographers use the white balance settings creatively to inject some colour and mood into their photographs. The Raw file format (stills only) allows the user to experiment with different white balance settings in the knowledge that they can always re-apply the correct setting afterwards. The white balance settings cannot be changed in images captured in other formats.

Ambient Light- The Sun

Artificial ambient lighting is more consistent than daylight, though it lacks the intensity of bright sunshine. In typical offices and classrooms the lighting has been arranged to illuminate the specific work being undertaken. The lighting in a lecture theatre is normally directed towards the front of the room while a classroom or laboratory will have a more general illumination. In these types of locations photographic lighting such as flash or film lighting will distract both the lecturer and students and so the photographer or filmmaker will probably have to use the available ambient lighting. Before the photographer or filmmaker starts capturing images they should try to identify the dominant light source in the environment, its brightness levels and if possible its colour temperature or type eg. tungsten. Colour temperature may be difficult to identify; currently most classrooms and offices use fluorescent lighting; however a lecture theatre may have a combination of fluorescent, dimmable tungsten lights and possibly the light of a projector. While the camera can auto white balance for the dominant light source the weaker sources will probably still contribute to the lighting in the scene and may introduce a local colour cast.

Camera shake is a common problem when photographing under low light levels this can be prevented by increasing the ISO or using a stable support. There is more information on camera supports in the JISC Digital Media document Stands and Supports for Still and Moving Images. While it should be possible to capture good quality images without disturbing the subjects it is essential that consent is sought before shooting in a classroom or lecture theatre.

Typical lighting in a lecture theatre

In environments where lighting is used to illuminate large public areas over long periods of time the priority is energy efficiency and visibility rather than accurate colour rendition. Street lights in the UK for example normally have a strong yellow bias which is very hard to correct for. While it may be hard or even impossible to remove the yellow cast, it is atmospheric and represents how the scene appears. If the photographer wants to capture the true colour of the subject they will either have to light the subject with artificial photographic lighting or wait for daylight to return.

Available street lighting

Artificial photographic lighting

Artificial photographic lighting is the light that the photographer or filmmaker has introduced to a scene to augment or replace ambient lighting. In most film or stills studios high power tungsten, fluorescent or flash lights are the most widely used artificial lighting systems though it is also quite common to find domestic lights such as a desk lamp or a torch employed to illuminate parts of a subject. Artificial photographic lighting is a stable light source with a known colour temperature; its brightness can be controlled either directly via a switch or dial or by moving it closer to, or further from the subject. With ambient lighting the photographer or filmmaker has to make the most of what is in the scene, however they can choose which type of artificial light to use based on the lights suitability for the task.

Flash

Flash is the standard artificial light source used in still photography and is built in to the majority of digital cameras. Bare flash bulbs are small light sources and produce very direct lighting unless modified (see small light sources below). Both flash and daylight have roughly the same colour temperature and so they can be used together without creating white balance problems. Flash is often used with bright sunshine to lighten up or ‘fill in’ dark shadows. Although flashes produce a lot of light and some heat it is rapidly dissipated and should not harm the average subject. The brief duration of a flash (can be measured in thousandths of a second) makes it highly effective at recording moving objects. However this also makes it impossible to preview the lighting before the image is taken. To ensure a correctly captured picture the flash has to be triggered at the moment that the shutter is completely open, this is achieved via a flash synchronisation circuit which links the flash to the camera. Detachable flashes connect to this circuit via electrical contacts on the camera’s flash mount or ‘hot shoe’, remote flashes can be synchronised via a synch cable, triggered by other flashes (slave flash), infra red or radio signals. Most cameras will have a maximum shutter speed for flash synchronisation, slower speeds will all synchronise correctly, exceeding the flash sync speed will result in incorrectly exposed images.

The small pop up flashes built into cameras are very effective for ‘fill in’ flash but their proximity to the camera’s lens can result in ‘red-eye’.

Pop-up camera flash

Red eye

When bright light enters the eye it illuminates the tissue behind the retina which glows red. This red reflection then shines back out of the eye towards the camera, the result is known as red eye. If ambient light levels are increased then the pupil in the eye will contract, reducing the amount of light entering and therefore reflecting back out of the eye. Some cameras offer a red eye reduction feature were the camera emits a rapid burst of pre-flashes, in response the pupil reduces in size just before the picture is taken. Red eye can also be avoided by switching the flash off and using available light or if possible ‘bouncing’ the flash or using it ‘off camera’.

Detachable flashguns offer greater flexibility; they can be pointed directly at the subject, reflected or ‘bounced’ off a nearby wall or ceiling or removed from the camera and operated remotely. Modern detachable flashguns can exchange information with the camera before and during the exposure to improve focusing and exposure.

 
Left, camera ‘hot shoe’ top middle of frame. Right, detachable flash mounted on camera’s hot shoe

Studio flash systems offer considerably more power than camera-mounted systems but they are also less portable. Studio flashlights are normally fitted with a tungsten modelling light which simulates the flashlight; this assists the photographer in focussing and composing the image. Modelling lights do however radiate a lot of heat and they should be used with care when photographing sensitive objects.

  
Left, studio flash ‘head’. Right, wireless (radio) flash synchronisation

Tungsten or incandescent lighting

Tungsten or incandescent lighting is used by both photographers and filmmakers. Tungsten lights have a warm coloured light with a colour temperature of around 3500K and therefore should not be mixed with bright daylight or flash unless tungsten to daylight colour correction (CC) gels are placed over the lights. The bare tungsten filament is a small light source and produces a very direct light unless it is modified (see small light sources below). Most professional tungsten lights are fitted with black adjustable flaps or ‘barn doors’ which can be opened, closed or rotated to control the area of illumination, they can also be closed over the light to protect the bulb when not in use.

These lights draw a lot of power and normally need to be connected to a 240V supply and are therefore not suited to location photography. For location work, film units with large Hollywood budgets use mobile generators to power their lights however small scale video projects normally have to make do with reflectors or small camera mounted ‘top lights’ to provide ‘fill’.

Tungsten lights are highly inefficient and produce a lot of heat and infrared light. Human subjects soon start to feel uncomfortable under the light and the radiant heat can damage delicate objects.  The light’s casing can get quite warm but some parts of the light close to the bulb such as the adjustable barn doors can get extremely hot and should only be adjusted when cold or with thick leather gloves. To avoid the risk of fire, flammable materials shouldn’t ever be attached to the light or placed close to it. For safety reasons these lights should never be left unattended.

Domestic tungsten sources such as adjustable desk lights can be used to illuminate small areas and are a low cost, though less bright alternative to specialist tungsten lighting.

Tungsten studio light with barn doors attached

Fluorescent studio lights

Fluorescent studio lights are popular alternatives to tungsten for both stills and video photography. They produce a continuous light with colour temperatures ranging from 3200K to 5600K. These lights are far more efficient than tungsten lights and produce very little heat, which makes them suited to lighting delicate objects. At present however fluorescent bulbs do not produce the same amount of light as a single studio tungsten bulb. To increase the brightness, fluorescent lights often incorporate an array of bulbs; these may be switch able to alter the light output (most fluorescents cannot be fitted with dimmers). With larger bulbs grouped together in a single head fluorescents generally produce a ‘soft’ illumination we associate with large light sources (see large light sources below).

Some fluorescents, particularly those used at home and in offices do not offer a full spectrum and may lead to inaccurate colour so it would be wise to run some simple colour tests before using these lights photographically.

Normal AC mains electricity alternates at 50 cycles per second (50 hz), this can create a rapid shift in brightness with many types of light, particularly fluorescents. If a number of frames are taken of the same subject a shift in colour or tone may be seen as different frames are captured at different points in the flicker cycle. Manufacturers are beginning to resolve this, though it would be wise to run tests to check for flicker. If there is a noticeable shift, reduce the shutter speed (and compensate by closing the aperture) then check the results.

Fluorescent studio light

LEDs

LEDs (Light Emitting Diodes) are generating a lot of interest particularly in video making where there is a demand for a portable, energy efficient daylight balanced lighting system. LEDs produce full colour spectrum light with a colour temperature of 5500K. Like fluorescents, these systems use an array of tiny LEDs to create a large bright light source. The more LEDs the brighter the light. They are very efficient and some systems can be used with 240v mains electricity, 12 volt DC or portable batteries. The small size of LEDs means that they can be incorporated into housings with compact form factors, which can be used in confined or difficult positions.

Small and large light sources

The relative size of a light source to the subject has a strong influence on the appearance of the lighting. A small light or ‘point source’ has high contrast between shadows and highlights; shadows will normally have clearly defined or ‘hard’ edges. A large light source produces a much ‘softer’ light with less contrast between shadows and highlights. The Sun is a very large light source however its great distance from the Earth makes it behave like a point source. Light rays from the Sun travel parallel to one another, this produces clearly defined shadows. On overcast days the clouds disrupt the light rays causing them to travel in all directions, this produces less clearly defined or ‘softer’ shadows. Small light sources include flash bulbs, bare domestic light bulbs and candles. Large light sources include general office lighting, reflected or ‘bounced’ light and north light. It is normally reasonably easy to convert a small light source into a large one but quite difficult to do the opposite.

         
Left, direct light rays from the Sun produce hard edges shadows. Right, diffused sunlight produces softer shadows

Modifying light

The quality of light in the natural world and how it illuminates the subject varies according to the position of the Sun in the sky and the prevailing weather conditions. By carefully adjusting the position of the light/subject or using large or small light sources the photographer or filmmaker can also radically alter the appearance of the captured image.

Modifying flash

Most digital cameras have built in flash units, their proximity to the lens makes them hard to modify and they often produce images with hard-edged shadows. A loop of light diffusing material such as tracing paper attached to the built in flash might ‘soften’ the light a little, for greater control over flash lighting a separate camera mounted flash may be required.

       
Left, camera firing built in flash. Right subject illuminated by a direct camera flash. Note the sharp edged shadows behind the books.

Detachable flash units may be directed or ‘bounced’ off a large white surface like a wall or ceiling or through a sheet of translucent material such as tracing paper. This in effect creates a large light source, which is less directional and produces a more even illumination. A lot of the light is lost when it is bounced or diffused and the photographer may have to adjust the camera’s exposure settings to compensate. It is important to check that the surfaces used for bouncing lights are not coloured as the colour is also reflected onto the subject.

      
Left, camera with flash pointing at a white ceiling (bounced flash). Right subject illuminated with bounced flash. Note less obvious shadows and lower contrast.

By moving a large light source closer the lighting becomes softer and more of the light will reach the subject. Moving it away from the subject makes the light harder and less light will reach the subject.

Modifying daylight

Ambient lighting is the lighting that exists in a scene before the photographer starts work. Daylight is the most familiar type of ambient light but it is also the hardest one to control, it can’t be switched on or off and often the photographer must work with what is available or wait and hope that the light improves. With daylight we are unable to move the light source (the Sun) to illuminate the subject from the desired angle though we may be able to choose a time of day when the Sun is in the right place in the sky to light the subject. Alternatively we may be able to move the subject. Strong direct lighting can produce harsh shadows, to compensate (if this effect is undesired) the subject can be moved into shade or the light can be diffused. Shadows can be ‘filled’ with bounced light from a reflector or with a little light from a flash (fill in flash) or top light on a video camera. Before the widespread use of specialist lighting many photographers and artists used studios with large north facing windows (in the northern hemisphere) to take advantage of the diffused light.

 
Right, filming under direct light. Left, subject illuminated directly from above.

The image above shows how direct light creates high contrast lighting with very strong shadows.

 
Right, filming in direct light with reflector. Left, subject illuminated from above with reflector lightening shadows.

The images above show how a reflector can be used to reduce the contrast and ‘fill’ the shadows, stills photographers can use the camera’s flash instead, this is known as ‘fill in flash’. While there are lots of commercially made reflectors available, a homemade reflector made from a piece of white card, polystyrene sheet or flip chart paper will produce similar results. For the best results the reflector should be positioned in the light facing the side of the subject which was in the shadow. The reflector can be curved around the subject to wrap the reflection around more than just one side.

 
Left, filming in open shade. Right, subject in open shade.

Another solution is to move the subject into open shade, the lighting will have much lower contrast and exposure values will change dramatically. This option may not always be desirable or possible. Another solution is to place an opaque board or semi transparent material between the subject and the light.

The soft light we associate with overcast daylight is very hard to modify with reflectors. If harder more directional lighting is required it will probably have to come from an artificial source such as a flash. Clouds also tend to absorb more of the ‘warmer’ wavelengths of light which can give images a blue hue. Careful use of the cameras white balance controls should reduce this.

Other types of ambient light include moonlight, domestic, office and classroom lighting. While the intensity is typically much lower than daylight or flash some of the above methods for modifying can be used to alter the appearance of the light.

Conclusion

Thanks to digital cameras it is now much easier for the casual photographer or filmmaker to produce good quality images under a wide variety of lighting conditions providing a few simple precautions are taken. If light levels are low, which is common in a classroom or lecture theatre then long exposure times may be an issue. In video the gain can be increased or in stills the ISO can be raised to reduce camera shake though the quality of the final image may be degraded slightly. A camera support may also improve quality and reduce shake - see our Stands and Supports document for more on this. In some environments it may be possible to switch additional lights on or off to adjust the light levels or even move them  to concentrate attention on the subject.

Last updated: 11 January 2010
Published in: Digitising analogue media | Creating new digital media
Tags: digitisation | hardware | lighting | photography | supports and stands | tripod

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Putting Things in Order: a Directory of Metadata Schemas and Related Standards

Last updated: 07 January 2010
Published in: Managing your digital resources
Tags: business & community engagement | metadata

Comments (0)

Summary

This directory provides a list of formal metadata schemas and related standards giving brief descriptions and links to further information. It complements JISC Digital Media’s series of advice documents on metadata, which the reader is strongly advised to read alongside this resource.

Introduction

A metadata framework can be viewed as having five key components:

• A schema (the categories of information you choose to record)
• Vocabulary (specific ‘words’ or ‘values’ you enter into those categories)
• Conceptual model - the underlying model that describes how all the information and concepts inherent in a resource are related to one another
• Content standard - practical standards that describe how specific information (e.g. vocabularies) should be entered within metadata schema categories (e.g. Cataloguing Cultural Objects)
• Encoding - which is concerned with the way the metadata is presented (e.g. XML)

This directory makes reference to all of these except metadata vocabularies which form a separate advice document, see:

• Controlling your Language: a Directory of Metadata Vocabularies

Readers should note that we are using “schemas” in a broad sense, to describe a set of categories (i.e. “elements” or “units”) of information used to describe resource.  As JISC Digital Media’s metadata advice documents describe, metadata schemas can be differentiated in many different ways, for example:

• Their size and scope (e.g. comprehensive or ‘core’; emphasis on description, administration, preservation; concern with single items or collections or both)
• Things they describe (e.g. art images, audio, video, objects, books, places)
• Communities they serve (e.g. libraries, museums, educators)

This document does not attempt to categorise the schemas and other standards: it presents them within an alphabetical listing. The descriptions will provide some information about their scope, but readers should refer to JISC Digital Media’s still image, moving image or sound specific advice documents for more context.

Furthermore distinctions between schemas, conceptual models, content standards, and encoding standards are often not fixed or discreet. Several metadata schemas describe their underlying conceptual models, provide guidance on what data might to be entered within their categories, or indicate how the metadata should be encoded. Dublin Core, for example, provides all of these.

Listing

Cataloguing Cultural Objects (CCO)

CCO is a data content standard, providing guidelines for entering data into schemas relating to cultural objects, particularly the VRA Core and CDWA Lite (see below). CCO was developed by the US-based Visual Resources Association (VRA) with significant input from the Getty Research Institute.

Main link:

• Official CCO web pages

Categories for the Description of Works of Art (CDWA)

CDWA is an extensive metadata schema for cataloguing objects held by art museums. It was developed in the US in the 1990s by the National Endowment for the Humanities (NEH), College Art Association (CAA), and J. Paul Getty Trust, and is maintained by the Getty Research Institute. A second edition of CDWA was published in 2000 and revised in 2006. An XML encoding of selected categories from CDWA was developed in 2005, called CDWA Lite. CDWA Lite is intended to work with the CCO data content standard (see above) and the OAI-PMH encoding and harvesting standard (see below).

Main links:

• Discussion of CDWA and CDWA Lite in our Metadata Standards and Interoperability advice document
• Official Categories for the Description of Works of Art (CDWA) web pages

Other useful links:

• Categories and Definitions [530KB PDF document]
• CDWA Lite
• Crosswalk between CDWA and other standards
• CDWA entry in JISC Standards Catalogue

CCO see Cataloging Cultural Objects

CDWA see Categories for the Description of Works of Art

CIDOC CRM see Conceptual Reference Model

CRM see Conceptual Reference Model

Conceptual Reference Model (CRM)

The CRM is a conceptual model, providing formal definitions and structures for describing the concepts and relationships used in cultural heritage documentation (e.g. by museums or archives). The CRM is not a metadata schema but can be used as a tool for analysing and mapping existing schemas or as a guide to creating new schemas. The development of the MIDAS standard (see below), for example, has been influenced by this model. CRM can be represented as XML and used within Semantic Web applications. The CRM was developed by the International Committee for Documentation (CIDOC) of the International Council of Museums (ICOM) and achieved ISO standardisation in 2006 (ISO 21127). There is an overlap between CRM and FRBR (see below) and there are efforts underway to harmonise these two standards.

Main link:

• Official CIDOC CRM web pages

Other useful links:

• Latest online version of CRM
• International Standard ISO 21127

DACS see Describing Archives: A Content Standard

DCMES or DCMI see Dublin Core

Describing Archives: A Content Standard (DACS)

DACS is a US content standard for archival description, based on ISAD(G) (see below). Published by the Society of American Archivists in 2004 and only available in print, it provides guidance on how information about archival resources might be entered into schemas such as EAD or MARC 21 (see below).

Main link:

• DACS publication details on the Society of American Archivists website

Other useful links:

• DCC Digital Curation Manual: instalment on archival metadata (2006)

Dublin Core

Dublin Core is a generic metadata schema (i.e. intended to be able to describe any type of resource) which has been widely used and adapted. Developed from the mid 1990s through a process of international collaboration, it is maintained by the Dublin Core Metadata Initiative (DCMI). In its simple 15-element form, Dublin Core has achieved NISO and ISO standardisation. In addition, there is also a larger set of elements and sub-elements (DCMI Metadata Terms) and several ‘application profiles’ (versions of Dublin Core developed for particular purposes). There are XML encodings of Dublin Core and a version for harvesting via OAI-PMH (see below). Many of the other schemas in this listing have been based on or influenced by Dublin Core. Most have established mappings to Dublin Core for the purpose of interoperability.

Main links:

• Discussion of Dublin Core in our Metadata Standards and Interoperability advice document
• Official Dublin Core website

Other useful links:

• International Standard, ISO 15836/NISO Z39.85
• DCMI Metadata Terms (the extended/qualified standard)
• Guide to using Dublin Core
• Dublin Core Abstract Model
• Dublin Core Encoding Guidelines
• Dublin Core entry in JISC Standards Catalogue

EAD see Encoded Archival Description

Encoded Archival Description (EAD)

The EAD metadata schema provides an XML encoding for archival descriptions. It adopts a multi-level approach to description, providing information about a collection as a whole and then breaking it down into groups, series and (if significant) individual items. EAD grew out of work done at UC Berkeley in the mid 1990s and was influenced by TEI and ISAD(G) (see below). Version 1.0 was released in 1998 with a major revision in 2002 (Version 2002). EAD is maintained by the US Library of Congress and Society of American Archivists, but is used internationally, including the UK. The DACS content standard (see above) provides guidelines for US archivists on how to enter data into EAD.

Main link:

• Official EAD web pages

Other useful links:

• EAD help pages
• EAD entry on Cover Pages website
• DCC Digital Curation Manual: instalment on archival metadata (2006)

EXIF (Exchangeable Image File Format)

EXIF is a technical metadata standard that can be written to and read from a still image file itself (JPEG and TIFF formats). It was developed by JEITA (Japan Electronics and Information Technology Industries Association) to enable camera manufacturers to write technical data into digital images (e.g. camera settings). Although primarily used by digital cameras, some scanners will also write EXIF data.

Main link:

• Unofficial EXIF website

Other useful links:

• Official JEITA website
• EXIF entry in Wikipedia
  (Wikipedia entries can be edited by anyone, so readers should be careful in relying on the information it provides)

FRBR (Functional Requirements for Bibliographic Records

FRBR is a conceptual model for describing information resources within a library context. It describes particular entities (e.g. Item or Person) and their relationships (e.g. Item is owned by Person). Like the CRM (see above) FRBR is not a metadata schema, but a model that can be used to analyse existing schemas or influence the development of new schemas or content standards. It is currently being drawn on in the development of the RDA content standard (see below). FRBR is an international model, published in 1998 by a working group of the International Federation of Library Associations (IFLA). A working group was established in 2002 to review and further develop the standard. One of its tasks is to look at how FRBR and the CRM (see above) can be related.

Main link:

• FRBR Final Report

Other useful links:

• FRBR Review Group
• FRBR entry in Wikipedia
  (Wikipedia entries can be edited by anyone, so readers should be careful in relying on the information it provides)

Functional Requirements for Bibliographic Records see FRBR

General International Standard Archival Description see ISAD(G)

IEEE LOM (Learning Object Metadata)

The IEEE LOM provides a metadata schema for describing learning resources. The first part of the standard, the set of metadata categories, was published in 2002. A later part, published in 2005, outlined how LOM was to be encoded as XML. The UK LOM Core (see below) provides a UK version of the IEEE LOM.

Main link:

• Official IEEE LOM website

Other useful links:

• Final draft of the standard
• Draft of XML-encoding standard
• IEEE LOM entry in JISC Standards Catalogue

IPTC (International Press Telecommunications Council)

IPTC is both the name of an organisation and a descriptive metadata schema. The IPTC schema can be written to and read from an image file itself.  From the mid-1990s, through the Council’s work with Adobe, it has been possible to embed IPTC metadata directly into the header of JPEG and TIFF image files. In 2005 the Council released “IPTC Core”, a standard for using IPTC within Adobe’s XMP schema (see below). This enables IPTC data to be incorporated (via XMP) into a wider range of image formats (e.g. JPEG, TIFF, JPEG2000, PNG, DNG, SVG). In July 2008 the IPTC Photo Metadata 2008 standard was released.

Main link:

• IPTC Official website

Other useful links:

• IPTC Core (IPTC Metadata for XMP)

ISAD(G) (General International Standard Archival Description)

ISAD(G) outlines metadata elements that should be used in the description of archival collections. . It adopts a multi-level approach to description, providing information about a collection as a whole and then breaking it down into groups, series and (if significant) individual items. ISAD(G) has influenced national archival standards and the development of the international archival encoding schema: EAD (see above) and the European SEPIADES schema (see below). ISAD(G) is in its 2nd edition, published in 1999.

Main link:

• International Council on Archives Committee on Descriptive Standards

Other useful links:

• Downloadable standard on the main ICA website
• DCC Digital Curation Manual: instalment on archival metadata (2006)

ISAN (International Standard Audiovisual Number)

ISANs can be compared to ISBNs (International Standard Book Numbers) for printed matter. They are a system of unique identifiers for analogue or digital resources which are used to ensure consistency across catalogues.

Main link:

• ISAN (International Standard Audiovisual Number)

LOM see IEEE LOM and UK LOM Core

MARC (Machine-Readable Cataloguing)

MARC is a family of metadata standards for representing library resources. Although chiefly used by libraries to describe bibliographic material (books or periodicals), it is also sometimes used to describe non-book material (e.g. images) or archival collections. MARC is a very extensive and formalised standard, with hundreds of potential categories and a rigid way of encoding its data. In the past, individual countries developed their own versions of MARC (e.g. UKMARC), but many are now converging to the current version: MARC 21 (published in 1999 and maintained by the US Library of Congress). MODS (see below) provides a sub-set of MARC encoded as XML, but there are also efforts underway to provide an XML encoding of the larger MARC standard (MARCXML). Many libraries have relied on the Anglo-American Cataloguing Rules for guidance on how to enter data within MARC, but this will be replaced by the new RAD content standard (see below).

Main link:

• Official MARC website

Other useful links:

• MARCXML
• Understanding MARC
• British Library web page on MARC and related standards

Metadata Encoding and Transmission Standard see METS

Metadata Object Description Schema see MODS

METS (Metadata Encoding and Transmission Standard)

METS is a standard for encoding metadata within an XML format. Although it contains descriptive and administrative elements of its own, a key function of the METS standard is to structure or “package” other metadata or data for exchange or delivery. METS can embed or link to other XML-based metadata (e.g. MODS, MIX, PREMIS or TEI, see below). Any number or type of digital files can be described and linked together by a METS record, enabling it to represent very complex digital resources (e.g. a whole digitised book, with bibliographic data, images and transcribed text). METS grew out of work in the mid 1990s on the Making of America II (MOA2) digitisation programme sponsored by the US Digital Library Federation. It is now maintained by the US Library of Congress. METS 1.1 was released in 2001; the current version is 1.5, released in 2005.

Main link:

• Official METS website

Other useful links:

• METS tutorial
• METS Awareness Training Project
• METS implementation registry
• METS entry on Cover Pages website
• METS entry in JISC Standards Catalogue

MIDAS Heritage: the UK Historic Environment Data Standard

MIDAS is a UK standard for describing cultural heritage assets that form the historic environment (buildings, archaeological sites, shipwrecks, areas of interest, artefacts and ecofacts). MIDAS was published by English Heritage in 1998 with slight revisions in 2000 and 2003. It is now being developed by the Forum on Information Standards in Heritage (FISH). In 2004 FISH published MIDAS XML, representing an improved version of MIDAS with XML encoding. The development of MIDAS has been influenced by both SPECTRUM (see below) and the Conceptual Reference Model (CRM, see above).

Main links:

• FISH Forum
• FISH Interoperability Toolkit

Other useful links:

• Download page for MIDAS standard
• Article on FISH and MIDAS in D-lib magazine
• MIDAS Heritage

MIX (NISO Metadata for Images in XML)

MIX is an XML-based schema for encoding the NISO Technical Metadata for Digital Still Images standard (see below). It is being developed and maintained by the US Library of Congress. MIX could be incorporated within any XML-based metadata, but is particularly intended for use within METS (see above). MIX is currently in its second version.

Main link:

• Official MIX web pages

MODS (Metadata Object Description Schema)

MODS is an XML-based metadata schema for encoding information about library resources (particular books). It is based on a subset of the MARC 21 standard (see above). The first (draft) version 1.0 was released in 2002. The current version is 3.2, published in 2006. MODS is maintained by the US Library of Congress and is often used with METS (see above).

Main link:

• Official MODS website

Other useful links:

• MODS Overview
• MODS user guide
• JISC Tech Watch report on MODS [35KB PDF document]
• MODS entry in Wikipedia
  (Wikipedia entries can be edited by anyone, so readers should be careful in relying on the information it provides)

MPEG-7 (Moving Pictures Expert Group)

MPEG-7 is a multimedia metadata schema which can be used to provide rich descriptions of digital image, digital video or digital audio content. One key strength of MPEG-7 is the ability to segment time-based media and attribute different metadata to each part. When constructed MPEG-7 was intended to take into account aspects of several other schemas such as: the SMPTE (Society of Motion Picture Technical Experts) Metadata Dictionary, Dublin Core, P/Meta and TV-Anytime. MPEG-7 can be used alone or as a technical metadata schema within models such as METS or MPEG-21.

Main link:

• MPEG-7 Overview

MPEG-21 (Moving Pictures Expert Group)

MPEG-21 has a similar purpose to METS (see above): providing an XML framework for “packaging” sets of metadata and files representing complex digital resources. Of particular interest is MPEG-21 Part 2: Digital Item Declaration Language (DIDL), which describes the digital resource, and Part 5: Rights Expression Language (REL), which details rights-related information (e.g. copyright). To date MPEG-21 has only been used experimentally with digitised collections.

Main link:

• Official MPEG website

Other useful links:

• MPEG-21 overview

OAI-PMH (Open Archives Initiative Protocol for Metadata Harvesting)

OAI is an important initiative to facilitate the interoperability of metadata records.  The OAI Protocol for Metadata Harvesting (OAI-PMH) provides a means of requesting metadata records from OAI-compliant repositories.  In other words, it works by ‘harvesting’ (from data providers) metadata that has been made available in a standard xml format. This harvested metadata can then be searched together from one place (from a service provider). In order to take advantage of OAI, those maintaining digital repositories or collections must provide an encoding of their metadata as simple Dublin Core (see above), although other metadata schema can be additionally supplied. The current version of OAI-PMH is 2.0, released in 2002.

Main link:

• OAI Official website

Other useful links:

• Open Archives Forum
• Implementation guidelines
• OAI-PMH entry in JISC Standards Catalogue

NISO Metadata for Images in XML Schema see MIX

NISO Technical Metadata for Digital Still Images

NISO Technical Metadata is a “data dictionary” rather than a formal metadata schema: a list of categories of data that might be used to describe the technical aspects of raster-based digital images (e.g. TIFF, JPEG, GIF). The standard is very lengthy and few if any implement it in its entirety. NISO Technical Metadata does not specify any particular encoding, so the MIX standard (see above) is being developed to represent it as XML for incorporation into other XML-based schema (e.g. METS, see above). NISO Technical Metadata has had a long development. Work began in 1999 and its current version was made available in 2006.

Main link:

• Official NISO Technical Metadata web page

Other useful links:

• Automoatic Exposure project

P/Meta

P/Meta is the European Broadcasting Union’s own metadata standard, developed by EBU members on a not-for-profit basis. It is intended to be used to exchange media between professional media broadcasting organisations
P/Meta was designed to be flexible and suitable for use in a wide range of broadcasting activities and be both language and system independent. P/Meta has, so far, not found wide support outside of the broadcasting industry.

Main link:

• European Broadcasting Union

PBCore

PBCore (or the Public Broadcasting Metadata Dictionary) is intended for use by television, radio and web broadcasters and hopes to be a standard way of describing and using this metadata, allowing content to be more easily retrieved and shared among colleagues, software systems, institutions, community and production partners, private individuals and educators. It can also be used as a guide for an archival or asset management process at an individual station or institution. As with other, primarily technical, metadata standards PBCore can be incorporated to cover technical metadata within structures such as a METS record.

Main link:

• PBCore
  

PREMIS

Like NISO Technical Metadata (above) PREMIS provides a “dictionary” of core metadata elements that can be used to support the digital preservation of a resource. PREMIS was based on an international survey of practice and on previous research and development. It was particularly influenced by a conceptual model called the Open Archival Information System (OAIS), which provides a conceptual framework for preserving digital (and non-digital) resources. The current version of PREMIS (1.0) was finalised in 2005 but planning has begun (in 2006) for version 2.0. The official website provides an XML-encoding for PREMIS, which is intended to facilitate its use with other XML-based metadata such as METS (see above).

Main link:

• Official PREMIS web pages

Other useful links:

• PREMIS Working Group website
• PREMIS entry in JISC Standards Catalogue
• DCC Digital Curation Manual: instalment on preservation metadata (2006)

RDA see Resource Description and Access

Resource Description and Access (RDA)

RDA is a data content standard (like CCO or DACS above), the online version of which is due for publication in June 2010.  RDA is intended to provide guidance on how data should be entered into library-based metadata schemas. It represents a major revision of an established library standard called the Anglo-American Cataloguing Rules (AACR). RDA will draw on the FRBR conceptual model (see above) and will focus on the use of library standards such as MARC (see above).

Main link

• Official RDA web pages

SEPIADES (SEPIA Data Element Set)

SEPIADES provides a metadata schema for describing archival photographic collections. It is closely based on ISAD(G) (see above), adopting a similar multi-level approach to description. SEPIDES was developed by the European-funded SEPIA Project (Safeguarding European Photographic Images for Access, 2000-2003). SEPIADES was published in 2003 as a set of “Recommendations for cataloguing photographic collections”. It does not provide a particular encoding, but in 2004 one of the SEPIA partners released a cataloguing tool that incorporates the standard and generate records in a Dublin Core format suitable for harvesting under OAI-PMH (see above).

Main links:

• Discussion of SEPIADES in our Metadata Standards and Interoperability advice document
• SEPIA Working Group on Descriptive Models

Other useful links:

• SEPIADES Recommendations for Cataloguing Photographic Collections [4MB PDF document]
• SEPIADES Software Tool

SMPTE (Society of Motion Picture Technical Experts) Data Dictionary

The metadata dictionary structure defined by the SMPTE dictionary covers the use of metadata for video, audio and multimedia data in their various forms. SMPTE metadata must conform to definitions published in the ‘dictionary
structure standard’ and the associated ‘metadata dictionary recommended practice’ (SMPTE RP 210). SMPTE RP 210 also defines a registered set of metadata element descriptions. Although the SMPTE dictionary forms the basis of many other descriptive schemas (such as MPEG-7). It is rarely used in isolation.

Main link:

• SMPTE (Society of Motion Picture Technical Experts)

SPECTRUM

SPECTRUM is a key UK standard for museum documentation. It recommends “units of information” that can be used to document museum procedures (and objects). First published in 1994 and currently in its 3rd edition (released in 2005), SPECTRUM is developed and maintained by the Collections Trust. 

Main link:

• Official SPECTRUM web page

Technical Metadata for Digital Still Images see NISO Technical Metadata

TEI or TEI-Lite see Text Encoding Initiative

Text Encoding Initiative (TEI)

TEI is a standard for describing and encoding literary texts. The first part of an encoded work (TEI Header) provides metadata about the work, while the remainder of the file ‘marks up’ the transcribed text, indicating chapters, paragraphs, and other noteworthy features. TEI was founded in 1987 with the first version released in 1990. However it is version P3 (1994) that most TEI implementers have used. TEI was based on SGML, a precursor to XML, so version P4 (2002) converted the standard into XML. The latest version (2007) is P5.  In addition, there is a simplified version of TEI, called TEI Lite.

Main link

• Official Text Encoding Initiative website

Other useful links:

• TEI Lite

TV-Anytime

Within the TV-Anytime metadata specification, the most visible parts of metadata are the attractors/descriptors (used in Electronic Program Guides (EPG) or in web pages to describe multimedia content). This is the information that the consumer uses to search and select content available from a provider. Another set of TV-Anytime metadata describes user preferences, representing  consumption habits, and defining other information such as demographics models, for targeting a specific audience. Whilst highlighting practical interactivity the TV-Anytime schema cannot easily be incorporated into other metadata models.

• TV-Anytime

UK LOM Core

The UK LOM Core provides a metadata schema for describing learning resources. UK LOM Core is a UK version of the international IEEE LOM standard (see above). It specifies a “core” set of LOM elements that should be used, and provides guidance on how data should be entered within the LOM‘s categories. The development of the UK LOM Core is being coordinated by CETIS (the Centre for Educational Technology Interoperability Standards) and the standard is still in a draft form (2004).

Main link:

• Official UK LOM Core web pages

Other useful links:

• UK LOM Core entry in JISC Standards Catalogue

VideoMD

VideoMD was designed by the Library of Congress and is a schema specifically constructed to describe the technical elements of digital video. The schema uses 36 top level elements and is expressed as XML (eXtensible Mark-up Language). VideoMD does not aim to cover all aspects of a video resource, only technical features. As such VideoMD is best used in conjunction with other systems, such as within METS records. Although the schema is well defined and detailed, at time of writing surprisingly few examples are available.

Main link:

• VideoMD

Visual Resources Association Core Categories see VRA Core

VRA Core

The VRA Core is a widely used metadata schema for describing art or cultural images, providing 17 core categories. The current version is VRA Core 4.0 (2007). VRA Core was originally based on CDWA, but later versions have been heavily influenced by Dublin Core (see above). The new version (4.0)  draws on the CCO content standard and provides an XML encoding for VRA Core.

Main links:

• Discussion of VRA Core in our Metadata Standards and Interoperability advice document
• Visual Resources Association Data Standards Committee

Other useful links:

• VRA Core 4.0
• VRA Core entry in JISC Standards Catalogue

XMP (Extensible Metadata Platform)

XMP is an XML-based open Adobe standard, used within Adobe’s imaging software and also by an increasing number of third parties. XMP can incorporate metadata from other schemas (such as Dublin Core and IPTC, see above) and write this data into an image file.

Main link:

• Official XMP web page

Other useful links:

• XMP entry on Cover Pages website
• XMP entry in Wikipedia
  (Wikipedia entries can be edited by anyone, so readers should be careful in relying on the information it provides)

Z39.85 see Dublin Core

Z39.87 see NISO Technical Metadata for Digital Still Images, Data Dictionary

Last updated: 07 January 2010
Published in: Managing your digital resources
Tags: business & community engagement | metadata

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Controlling your Language: a Directory of Metadata Vocabularies

Last updated: 07 January 2010
Published in: Managing your digital resources
Tags: business & community engagement | metadata

Comments (0)

Summary

This directory provides details of more than 70 vocabulary sources. It categorises the various types of vocabularies available to us as Thesauri, Subject headings, Authority lists and Classification schemes. Thesauri, subject headings and word lists more generally, are used primarily in aiding retrieval, whereas Classification schemes help us to organise resources, and Authority Lists help us to standardise the expression of values used in our metadata, like, for example, the way we enter names and dates.  Although there are overlaps, broadly speaking each serves a different purpose in helping to control the terminology used in our schemas and in aiding the search and retrieval of our resources.

Contents

1. Introduction
2. Thesauri, subject headings, and word lists
3. Classifications
4. Authority lists
5. Conclusion

1. Introduction

There are many vocabulary sources already available and it makes sense to check these out before inventing your own. Depending on your particular needs you might find yourself:

• Using an existing controlled vocabulary as it is
• Adapting or customising a vocabulary - e.g. deciding to use a classification or thesauri to a particular level of detail
• Developing your own vocabulary - not recommended, but sometimes the best solution
• Using “uncontrolled” vocabulary - i.e. keywords entered by your cataloguers or, more radically, your users

Of course, you could also use a combination of these approaches. It is quite reasonable to use multiple vocabularies, for example, a formal controlled vocabulary plus additional keywords the cataloguer thinks will assist in retrieval.

In choosing a vocabulary, you should bear in mind:

• Your users - are the terms used going to be meaningful to them?
• Your community - it makes good sense to use vocabularies that similar collections are using
• The nature and extent of your collection - if your collection is small, you’re unlikely to need a highly detailed vocabulary
• The skills and available time of your cataloguing staff - some of these vocabularies will require experience or training to use properly
• Copyright issues - you may need to check whether permission or a license is required to use the vocabulary in the way you wish to

This directory presents a selection of formal vocabularies, most of which are available via the Internet. Brief introductions are given to the different types of vocabularies and their uses.

2. Thesauri, subject headings, and word lists

Thesauri, subject headings and word lists are sources of subject terms and their primary purpose is to aid retrieval.

A thesaurus orders its words hierarchically. If you look up a particular term (e.g. houses), you are likely to find references to Broader Terms (e.g. buildings), Narrower Terms (e.g. cottages), or Related Terms (e.g. palaces - terms which are different, but overlap in meaning). Where there are different words with the same meaning (e.g. houses and dwellings), a thesaurus will also tell you which is the preferred term (e.g. “dwellings, USE houses”). The thesaurus’s hierarchical structure is intended to help you find a suitable subject term at the appropriate level of detail.

Typical thesaurus entries

dwellings
USE houses

houses
BT=buildings
NT=cottages
RT=palaces
USE FOR dwellings

Subject headings are often arranged like a thesaurus, so the distinction is not always clear. However, instead of giving you a single term or phrase to use, as a thesaurus does, subject headings often enable you to link or coordinate terms to produce long phrases or strings of terms (this is sometimes referred to as ‘pre-coordination’). For example, the Library of Congress Subject Headings (LCSH) bring together the concepts “Art” and “War” to form the heading “Art and war”. You can further coordinate this with headings for particular wars, for example “World War, 1939-1945 - - Art and the war” (this latter example, using the ‘- -’ notation, is known as ‘subdivision’ - dividing up a main concept with another concept). The published LCSH is very big, including 270,000 pre-formed headings, but because of the way headings can be coordinated and sub-divided, the total number of potential headings is incredibly vast.

Sometimes people use thesauri to generate subject headings, for example “buildings - houses - cottages” (from our thesauri example above). This goes against traditional indexing practice, which insists that you take the thesauri term at the appropriate level and don’t include any of its broader terms, but it can make good sense in the age of digital retrieval. If we only added “cottages” to a record, a search on “buildings” would not retrieve it (unless the search software was quite sophisticated). So in this example, including the broader terms in the hierarchy would greatly improve the search results. Some cataloguing systems now do this automatically - if you choose a term from their thesaurus, they automatically insert all of the broader terms into the catalogue record. This kind of practice is blurring the distinction between thesauri and subject headings.

We’ve included the term “word lists” in our heading for this section to catch the simpler lists of words that are not coordinated like subject headings or organised hierarchically like thesauri. These sorts of vocabularies are, typically, simple alphabetical lists of terms or phrases. They’re also often created locally, for particular projects or institutions. The IEEE 1998 Keyword List (see below) offers an example of such a word list, although this is probably much longer than any list you would produce ‘in-house’.

2.1 General thesauri, subject headings and word lists

• Australian Pictorial Thesaurus (APT)
• Library of Congress Moving Image Genre - Form Guide
• Library of Congress Subject Headings
• Library of Congress Authorities
• National Digital Archive of Datasets (NDAD) Thesaurus
  (Based on UNESCO thesaurus)
• SEARS Subject Headings
• Thesaurus for Graphic Materials (TGM) 1: Subject Terms
• Thesaurus for Graphic Materials (TGM) 2: Genre and Physical Characteristics
• Thinkmap Visual Thesaurus
• UK Archival Thesaurus (UKAT)
  (Based on UNESCO thesaurus)
• UNESCO Thesaurus
• WordNet (Princeton University)

2.2 Specialist thesauri, subject headings and word lists

2.2.1 Arts and Humanities

• Art and Architecture Thesaurus (AAT)
• ARTLex Art Dictionary
• British Museum Materials Thesaurus
• British Museum Object Names Thesaurus
• Glossary of Technical Theatre Terms
• HASSET - Humanities and Social Science Electronic Thesaurus (UK Data Archive)
• ICOM Vocabulary of Basic Terms for Cataloguing Costume
• International Index to Film Periodicals: Subject Headings
• National Monuments Record Thesauri
  Set of thesauri relating to monuments and structures
• Understanding Illuminated Manuscripts: A Guide to Technical Terms
• Words of Art

2.2.2 Science

• Agrovoc Thesaurus (UN Food and Agriculture Organisation)
• Alexandria Digital Library Feature Types Thesaurus
  Categorises features relating to geographic locations
• Biocomplexity Thesaurus
• BIOSIS Controlled Vocabulary
  Covers life sciences
• CAB Thesaurus
  Covers applied life sciences
• Canadian Thesaurus of Construction Science and Technology
• Connecting Mathematics
• eHealth Thesaurus
• ERIC (Educational Resources Information Clearinghouse) Thesaurus
  Covers educational topics
• General Multilingual Environmental Thesaurus (GEMET)
• GeoRef Thesaurus
  Covers geological topics
• IEEE 1998 Keyword List
  List of keywords, mostly relating to electronics and computing
• INSPEC Thesaurus (Institute of Electronic Engineers)
  Covers Information Technology topics
• MeSH Medical Subject Headings (US National Library of Medicine)
• Multilingual Thesaurus of the Geosciences (MULTHES)
• NASA Thesaurus - Vol 1 and Vol 2
• National Agricultural Library’s Thesaurus (NALT)
• Terms of the Environment
• Zoological Record Thesaurus

2.2.3 Social Science

• ASIS Thesaurus of Information Science
• British Education Index Thesaurus
• Eurovoc Thesaurus (European Union)
  Covers topics relating to the EU
• GEM Controlled Vocabularies
  Educational Teminology
• Global Legal Information Network (GLIN) Thesaurus
• International Thesaurus of Refugee Terminology (ITRT)

3. Classifications

Classifications are sources of subject categories and their primary purpose is to organise resources.

Traditionally, the main purpose of subject headings and thesauri terms was retrieval, while classification schemes were more about putting things ‘in their place’ on a shelf, in a box, into a category, etc. Generally (there have always been exceptions), an item would be assigned many different subject terms, but only one classification. This makes perfect sense in a physical world, but in the virtual world there is no reason why something shouldn’t have more than one ‘location’. So the distinction between classifications and subject terms is beginning to break down.

Classifications are usually hierarchical: they start off with broad subject areas and then break them down into increasingly narrower topics. In this way they resemble thesauri, but classifications are generally much more rigid in their structure. While it is entirely feasible for a thesaurus term to have more than one broader term (this is known as ‘polyhierarchy’), a classification scheme will break down its subject domain in just one way. Because of this, classifications offer a single ‘world view’, imposing a structure that is never going to satisfy every user. And, unlike thesauri terms, classification schemes declare their structural biases openly through the numbers and codes they employ. For example, in the Dewey Decimal classification resources on Buddhism are usually classified at “294”. These digits are meaningful: the 200s are for “Religion”; the 290s, “Other and comparative religions” (note that most of the numbers from 200-289 are devoted to Christianity); and the 294s, “Religions of Indic Origin”. Here the nineteenth-century Western world view upon which the Dewey classification is based becomes apparent.

The classification scheme’s use of codes or numbers is the other important feature that distinguishes it from other kinds of controlled vocabulary, which are word-based. This coding can be used to advantage in a digital context, especially if it is based on a decimal system, like Dewey or the UDC (see below). Since numbers are much more “machine-readable” than words they can be used to advantage in searching. For example, searching for all the Dewey Classifications beginning with “2” would retrieve items relating to religion. They can also be used to generate hierarchical browse interfaces: users might be shown the first 10 subject categories, then choose one of these to view 10 sub-categories, then one of these to look at the next level… etc. Some of those building online collections are taking advantage of these opportunities.

3.1 General classifications

• BLISS Classification
• Book Industry Communication (BIC) Standard Subject Categories
• Dewey Decimal Classification (DDC)
• Library of Congress Classification (LCC)
  LCC Outline
• Open Directory Project categories
  Entire category structure can be downloaded in XML
• Universal Decimal Classification (UDC)

3.2 Specialist classifications

3.2.1 Arts and Humanities

• ICONCLASS
  Covers art history iconography

3.2.2 Science

• ACM Computing Classification System
• Mammal Species of the World
• Mathematics Classification Scheme
• Physics and Astronomy Classification Scheme

3.2.3 Social Science

• Learning Directory Classification System
  Course classification system
• International Standard Classification of Occupations (ISCO)
• International Family of Economic and Social Classifications (United Nations)
• JACS educational subject classifications
• Classification of HE disciplines and subjects
• North American Industry Classification System (NAICS)
• PAIS International Broad Topics Classification System
• United Nations Standard Products and Services Code (UNSPSC)
• Integrated Public Sector Vocabulary (IPSV)
  Covers topics relating to the UK government

4. Authority lists

Authority lists help you control names.

The other main grouping of controlled vocabularies are “authority lists” or “authority files”. These are sources of proper nouns (e.g. people, organisations, places). Names and places could be included in general thesauri or subject headings, but it makes sense to keep them in separate lists or databases.

Some institutions are cataloguing resources related to internationally known figures, such as authors and artists. In these instances, they can draw on common authority lists like the Library of Congress Authorities (see below), which includes the names of nearly 4 million individuals. Other institutions, like archives and museums, have resources relating to people that are not widely known. They cannot draw these names from a common list, but must create their own authority records, using particular rules like the ISAAR(CPF) or the UK National Council on Archives Rules (see below).

There are several online sources of place names listed below. Other sources could include atlases or official maps. Increasingly, digitisation projects are adding other place references such as postcodes or geospatial coordinates.

4.1 Name authorities

• International Standard Archival Authority Record for Corporate Bodies, Persons, and Families (ISAAR(CPF))(International Council on Archives)
• Library of Congress Authorities
• Namebase
• Rules for the Construction of Personal, Place and Corporate Names (UK National Council on Archives)
• Union List of Artist Names (ULAN)

4.2 Place authorities

• Alexandria Digital Library Gazetteer Service
• Getty Thesaurus of Geographic Names (TGN)
• Global Gazetteer
• Library of Congress Authorities

5. Conclusion

If chosen and managed carefully, controlled vocabularies can make cataloguing easier and improve the retrieval and presentation of items from your collection. Careful choice and management of vocabularies are key as:

• Vocabularies can improve retrieval, but only if the terms are obvious and meaningful to your users. If you’re using a small or specialised vocabulary, it will greatly assist your users if they can call up a full list of the terms you’ve used. Consider using multiple vocabularies and adding additional keywords (in another field) to aid retrieval.
• Vocabularies can improve cataloguing consistency, but only if everyone cataloguing your resources is using the vocabulary in a consistent way. It is vital that you write clear guidelines on what aspects of the image or object to describe, produce scope notes for the terms used (including examples), and regularly check and compare work.
• Vocabularies can help your collection ‘interoperate’ with other collections, but only if you’re using the same vocabularies and in the same way. If you adapt or customise a vocabulary you must record the changes you’ve made and you should be aware that you’re reducing the chances of fully interoperating with others.
• Some vocabularies will save you time and money; others might add to your costs, especially if they require a lot of expertise or intellectual effort. Where possible, automate the cataloguing process: use thesauri management software, cut and paste rather than retype.

JISC Digital Media has more information about metadata:

• An Introduction to Metadata
• Metadata Standards and Interoperability
  
• Metadata and Digital Images
• Metadata and Audio Resources
• Metadata and Digital Video
• Putting Things in Order: a Directory of Metadata Schemas and Related Standards
• Approaches to Describing Images

JISC Digital Media also runs a training course:

• Introduction to Image Metadata

Other vocabulary information on the Web:

• Taxonomy Warehouse (Synapse)
  Database of vocabulary sources
• HILT Project (University of Strathclyde)
  Project looking at mapping different vocabularies for interoperability
• Collections Trust
  Hosts several online thesauri and provides links to others
• Barbara Lute’s Web Thesaurus Compendium
  Links to vocabulary sources

Last updated: 07 January 2010
Published in: Managing your digital resources
Tags: business & community engagement | metadata

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Metadata Standards and Interoperability

Last updated: 07 January 2010
Published in: Managing your digital resources
Tags: delivery | digital collections | digital preservation | metadata | standards

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Summary

This advice document aims to provide a comprehensive look at the various choices the developer of multimedia collections has in terms of metadata standards and the principles behind using them. It attempts to provide a synopsis of general metadata trends, a) in usage for audio, moving and still image format types; b) in specific areas of practice such as museums, archives, libraries and education; and, c) in various activities and tasks such as preservation, interoperability and resource discovery. For an overview of the whole series of papers, and an introduction to the metadata issues discussed here, please see An Introduction to Metadata.

Contents

• Why use existing standards?
• What exactly do we mean by ‘standards’?
• What metadata standards are there?
• Community specific metadata schemas
• Task specific metadata schemas
• Application Profiles
• Metadata vocabularies
• Content standards
• Conceptual models
• Embedded metadata
• Conclusion

Why use existing standards?

While you could choose to make up your own metadata schemas and vocabularies from scratch, for various reasons it is generally preferable to use or adapt existing standards. Using an existing standard can offer:

• Cost saving - you won’t need to develop the schema, its usage guidelines or vocabularies yourself;
• Access to help and advice - a given standard is likely to have a community of users that has built up over time, which is likely to mean there will be comparatively easy access to help and advice about how best to use the standard.
• Usability - if your users are already familiar with your metadata structure or terminology they can more quickly and easily use your collection
• Resource discovery - your collection could be more easily opened up to be searched and shared by others;
• Sustainability - your use of common standards would make it easier to pass your collection on to someone else to look after if you ever need to

The last two advantages in this list (resource discovery and sustainability) are particularly concerned with ‘interoperability’ - the ability of your collection to work alongside other collections, either through shared resource discovery services or by contributing your metadata to other collections.

Interoperability depends on either the strict use of common standards or by understanding how your ‘non-standard’ metadata can be mapped to or transformed to common standards. When deciding on metadata for your collection, in addition to thinking about the collection itself and its specific needs, you will need to ask yourself whether it’s important for you to interoperate with other analogous collections.  If you do, it is likely to influence your choice and usage of standards.

What exactly do we mean by ‘standards’?

The word ‘standard’ can be problematic, since people use this term in different ways. If you’re seeking formal internationally approved metadata standards (often called de jure standards), then you’ll find very few. But if you’re looking for metadata schemas or vocabularies with reasonably wide endorsement and use, then you’ll find many more de facto standards.

Instead of adopting a narrow definition of ‘standards’, JISC Digital Media suggests that standards can be thought of as: commonly used and consistently applied formats or processes, which are measurable, well documented, and endorsed by someone. Such ‘standards’ will be found throughout your digital collection and workflows: e.g. file formats, digitisation workflow, Web delivery and - the focus of this paper - your metadata.

JISC Digital Media recommends:

• Where there are clear and obvious standards for your resource type, community, or task, make use of them
• Where the standards are unclear and competing, follow models of ‘good practice’ within your community
• Where you can find no appropriate standards or models, adapt an existing standard to better fit your needs and document the changes you make very carefully using the documentation methods and mappings deployed by existing standards as a guide

What metadata standards are there?

If you’re doing some research into metadata you’ll encounter many different standards, often with long names or confusing acronyms. It can sometimes be difficult to know which are the most relevant for your collection.  JISC Digital Media’s documents on metadata schemas and vocabularies are also intended to provide help in understanding and choosing standards. These should be read alongside this current paper:

• Putting Things in Order - a Directory of Metadata Schemas and Related Standards
• Controlling your Language - a Directory of Metadata Vocabularies

The remainder of this paper introduces several metadata standards of particular relevance to multimedia collections. It concentrates on metadata schemas (standards describing the categories of information you might record). It also briefly considers metadata vocabularies (standards describing specific terms that could be entered within the schemas categories) and two other special kinds of metadata standards: conceptual models and content standards (these are defined below).

Dublin Core

The Dublin Core (DC) is one of the most widely used schemas and illustrates many of the issues you’ll need to think about when choosing or adapting a metadata schema. If you can’t find a more suitable schema for your collection, then DC would be a good starting point.

DC was originally conceived as an attempt to provide a set of ‘core’ metadata properties that were able to provide a basic description of any type of resource, including individual items such as image, video, sound and text resources and composite resources such as websites.  DC is one of the few metadata schemas that has achieved international standardisation (ISO15836).  Due to its generic - sometimes referred to as ‘lowest common denominator’ - nature DC is often used as a basis for extending and adapting to better describe a specific resource, and it also increasingly provides the means for a basic level of interoperability between and across separate digital collections.

The table below lists the 15 elements or categories of DC, along with their formal definitions and two examples.

In the examples above, we’ve shown how DC might be used to catalogue a physical object (painting) or a digital object (image file). We might also have included a record describing a whole collection of physical or digital resources.

If you compare the two examples given, you’ll notice that while the elements are the same for each record, some of them are filled in very differently depending on what is being described (see, for example, Date and Format).

Some other metadata schemas take a different approach, choosing to include information about an original item and its digital reproductions within the same metadata record (the CDWA and SEPIADES schemas described below do this). DC creates separate records because it adopts a principle known as “one-to-one”. This principle states that a metadata record should only refer to one thing. If there are different ‘layers’ within an image (e.g. an original work and several reproductions of that work) then DC expects you to create a different record for each, as we have above. Similarly, if there are different ‘levels’ that you need to describe (e.g. collection, group of images, single image) then each of these will need to have their own records.

We’ve presented the simple, 15-element standard version of DC above, but people frequently add other elements (e.g. Audience or Provenance). It is also very common to “refine” or “qualify” a DC element in order to provide more information about the data contained within that element.

The DC initiative has suggested some refinements and those building digital collections frequently add others. For example, the Date element might be usefully broken down further (Date - Created, Date - Available, Date - Modified…). The Relation element is another good example. Looking again at the two example records above, it is clear that the two things being described by these records are related to each other. But the nature of the relationship is not stated. The table below shows how we might qualify the Relation element further to make the relationship clearer:

This indicates that Record B (the digital image) is a surrogate of Record A (the original painting).

Where possible, it is better to qualify an existing element rather than create a new separate element. Then, if you need to, you can always collapse your richer, qualified metadata back into its core element for the purposes of interoperability (e.g. exchanging records with others). In doing so, you will have lost some refinement, but you won’t have lost any data. This method - of being able to collapse your data into a broader category - is sometimes referred to a ‘dumbing down’ your metadata.

It is likely however that you may need to extend the DC element set with some additional elements. DC focuses more on describing resources, than administering them. So if you’re using DC as the basis for your metadata you’ll probably choose to add a few administrative or technical metadata elements to help you manage your collection. You might, for example, want to add elements to record which camera was used to capture the digital image (e.g. Capture Device), or any conservation work done to the original painting (Conservation), or perhaps any corrections made to the digital image (Optimisation). Although these non-standard metadata additions are not going to be as interoperable (since they can’t be ‘dumbed down’ to a standard DC category), this is not so critical since this information is unlikely to be used in search and retrieval and probably won’t even be shown to the users of your collection.

When adding new elements to DC, it is preferable to draw on other metadata standards where possible. Recently, quite a lot of attention has been paid to technical and preservation-related metadata (see NISO Technical Metadata and PREMIS, below), so you could use some categories from these standards to supplement DC.

Your adaptation of DC will result in a particular version of the standard that suits your needs. If a number of different collections have similar needs and are interested in interoperating in some way, then it makes sense to standardise these adaptations. Sometimes this has led to the development of new standards that are based on (and mapped to) DC, such as the UK e-Government Metadata Standard (e-GMS), or the development of Application Profiles that use DC as a base (see section on Application Profiles below).

Visual Resources Association Core

The Visual Resources Association Core (VRA) is a widely used metadata schema for describing works of visual culture and their associated images. It takes its name from its developing body: the Visual Resources Association, which is a US based association of visual resource librarians and associated image media professionals. VRA Core can be seen as an extension of DC aimed specifically at visual resources and has been influenced also by other initiatives in the field like the Categories for the Description of Works of Arts (CDWA) standard (see below).

Like DC, in its early versions VRA Core adopted the one-to-one principle, although it made a distinction between: original works (e.g. a painting, building or born digital work) and digital and analogue surrogate images of works (e.g. slides, prints or digital photographs).  VRA Core 3 presented the same 17 categories for both its Work and Image records, and like DC, they were filled in differently depending on what was being described.

The table below lists the 17 elements of VRA Core 3.0, along with their formal definitions and some examples.

VRA Core 3.0 also recommended some qualifiers (e.g. ‘Date.Creation’ or ‘Date.Restoration’) and some controlled vocabularies. As with users of DC, those using the VRA Core will frequently find they need to add new qualifiers or extend the schema with additional categories. For example, the African & Asian Visual Artists Archive collection hosted by the Visual Arts Data Service (VADS) decided to refine the VRA‘s image categories with elements like ‘Colour Space’, and ‘Compression’ to accommodate some additional technical metadata.

In 2007 VRA Core 3 was superseded by Core 4.  The new version has been influenced by two recent trends in the development of metadata: (a) the use of XML to encode and express the schema; and (b) increased attention to the way data is entered within the categories. There have been a number of modifications and structural changes to a number of the elements to take account of XML coding, as well as the addition of four new elements. The changes are:

Please visit VRA Core 4.0 for further information on the element outline and element descriptions and tagging examples and links to related resources.

CDWA (Categories for the Description of Works of Arts)

Like the VRA Core, CDWA is a standard for cataloguing cultural objects, such as those found within museums and galleries. With 512 categories or sub-categories it is much more detailed and extensive than VRA Core. Recognising that such a lengthy standard is too much for many institutions or collections, the CDWA identifies a set of 35 core categories which should be used as a minimum. During 2005-6 a revised version of the CDWA was prepared and released, reflecting the development of the Cataloguing Cultural Objects (CCO) content standard (see below). At the same time an XML version of CDWA has been released, called CDWA Lite. As its name suggests, CDWA Lite only encodes a subset of CDWA categories. The table below shows the main elements of CDWA Lite (but excludes its sub-elements):

Note that unlike DC and VRA Core, both CDWA and CDWA Lite include information about the original work and any digitised images of it within the same metadata record. All of CDWA‘s elements are repeatable, so it is possible to include multiple resource descriptions within the same metadata record to describe different views of an object or different versions of digital images.

CDWA Lite concentrates on those CDWA elements that are covered by the new CCO standard (see previous section) so it bears a close similarity to the VRA Core. CDWA Lite also conforms to an important standard used in interoperability, OAI-PMH (see Interoperability metadata, below). This has the potential to enable collections using CDWA Lite to share their metadata records more easily with others. 

SEPIADES (SEPIA Data Element Set)

In 2003 a European-funded project called SEPIA (Safeguarding European Photographic Images for Access) published a set of recommendations for describing photographic collections, which are known as SEPIADES. The SEPIA project focused on photographic archives, so the metadata it recommended was closely modelled on archival metadata, especially the General International Standard for Archival Description (ISAD(G) - see Archival schemas, below). The archival approach to metadata is hierarchical or “multi-level”: it creates a single metadata record for a whole collection of items, and then breaks the collection down into groups and, where significant, individual items.

SEPIADES adopts the same approach. The diagram on the right illustrates the parts of a SEPIADES metadata record. It begins by providing information about the photographic archive (Institution), then the source of the photographs (Acquisition), then discreet collections or sub-collections (Collection, Grouping), and finally individual works (Single Item).

At the Single Item level, SEPIADES makes a distinction between a “Visual Image” (i.e. its visual content) and its “Physical Description” (the particular material form it takes). Physical Description is further divided up into “Photographs” (which includes negatives, slides and prints) and “Digital Photo File” (which includes born-digital or digitised images). The table below shows the information SEPIADES recommends recording for a Single Item. The dashes indicate sub-categories.

In addition to its metadata standard, one of the SEPIA partners developed an open-source JAVA-based cataloguing system to record SEPIADES records. This system provides data entry and search facilities, and it also exports SEPIADES records as DC in OAI-PMH compliant XML (see Interoperability metadata, below).

Although SEPIADES is ideally suited to a photographic archive, its relationship to ISAD(G) means that elements of it could be incorporated within other archival metadata frameworks. The Single Item metadata could also be used independently as the basis of a collection’s metadata or could be used to supplement another core schema.

PB Core

PB Core (or the Public Broadcasting Metadata Dictionary) is intended for use by television, radio and web broadcasters and aims to be a standard way of describing and using multimedia content (including video, audio and still image), allowing it to be more easily retrieved and shared among colleagues, software systems, institutions, community and production partners, private individuals and educators. It can also be used as a guide for an archival or asset management process at an individual station or institution. As with other metadata standards PB Core can be incorporated to cover multimedia metadata within structures such as a METS record.  PB Core is based on DC and organises its fifty three elements in ‘containers’, which in turn are organised in four classes.  Which are:

• PBCoreIntellectualContent (metadata elements describing the actual intellectual content of a media asset or resource)

• PBCoreIntellectualProperty (metadata elements related to the creation, creators, usage, permissions, constraints, and use obligations associated with a media asset or resource)

• PBCoreInstantiation (metadata elements that identify the nature of the media asset as it exists in some form or format in the physical world or digitally)

• PBCoreExtensions (additional descriptions that have been crafted by organisations outside of the PBCore Project. These extensions fulfil the metadata requirements for these outside groups as they identify and describe their own types of media with specialised, custom terminologies unique to their needs and community requirements)

The table below shows the PB Core elements with their definitions and content classes. More information on these elements, along with examples of use, can be viewed at the PB Core website.

You will notice how many of these elements are based on DC.  Indeed, the PB Core schema is essentially an application profile for the broadcasting industry whose elements combine DC and others, and provide pointers to specific controlled vocabularies and structured values and can be expressed in XML.

PB Core is intended to be used by a wide range of expert and non-expert users in the public broadcasting domain, and therefore is intended be as ‘simple’ in the sense that DC is, but to also facilitate useful exchange of information.  Also like DC, PB core is intended to be used as basic starting point, and users of the schema are encouraged to add their own extensions and element qualifiers where appropriate.

MPEG-7 (Moving Picture Experts Group)

MPEG-7 is a multimedia metadata schema which can be used to provide rich descriptions of digital image, digital video or digital audio content. One key strength of MPEG-7 is the ability to segment time-based media and attribute different metadata to each part. When constructed MPEG-7 was intended to take into account aspects of several other schemas such as: the SMPTE (Society of Motion Picture Technical Experts) Metadata Dictionary, DC, P/Meta and TV-Anytime. MPEG-7 can be used alone or as a metadata schema within models such as METS or MPEG-21.  The standard achieved ISO status in 2001 (ISO/IEC 15398).

Formally called the Multimedia Content Description Interface, the standard focuses on representing information about the content, and not the encoding of the content itself, as was the case with MPEG 1, 2 and 4 standards.  MPEG 7’s broad aims are to provide a standard for:

• A core set of Descriptors (Ds) that can be used to describe the various features of multimedia content
• Pre-defined structures of Descriptors and their relationships, called Description Schemes (DSs)
• A language to define Description Schemes and Descriptors, called the Description Definition Language (DDL)
• Coded representations of descriptions to enable efficient storage and fast access

The standard also allows for additional information for organising, managing, and accessing the content, such as:

• Information about how objects are related and gathered in collections
• Information to support efficient browsing content (such as summaries, variations, and transcoding information)
• Information about the interaction of the user with the content (such as user preferences and usage history)

Moreover, in addition to standard archival type descriptors that relate to the content’s production processes (e.g. titles, locations, actors etc.), storage formats and copyright, MPEG 7 provides scope to record detailed descriptions of information within the content itself, such as:

• Information regarding the content’s spatial, temporal, or spatio-temporal structure (for example, scene cuts, segmentation in regions, and region motion tracking)
• Information about low-level features in the content (for example, colours, textures, sound timbres, and melody descriptions)
• Semantic information captured by the content (for example, objects, events, and interactions between objects)

MPEG 7 is therefore a relatively comprehensive metadata standard (at time of writing comprising twelve parts), that aims to provide descriptors for multimedia content that are useful across a wide range of domains and applications; that describe varying levels of abstraction - from low level descriptions like size and colour, to positional descriptors (i.e. where in a scene is a specific object), to high level semantic descriptors about what’s in the actual content itself.

Its descriptors are not laid out in list form like, for example DC, but rather form part of a series of methods and tools that can be altered depending on viewpoint.  Here is a simple example record which is describing the MPEG logo, taken from the article ‘Introduction to MPEG 7’ at MPEG Industry Forum:

Community specific metadata standards

The previous sections have highlighted schemas that are directly related to image and multimedia collections or, in the case of DC, are non prescriptive in the types of resources they can describe. In addition to these, there are also community specific metadata standards that have been developed by the Museum, Library and Archive communities, and emerging standards developed for Educational resource use. Some of these will be used to describe image and multimedia resources, particularly in these communities or in situations where systems developed primarily for these communities are being utilised elsewhere.  Web links and further information are provided in JISC Digital Media’s Putting Things in Order - a Directory of Metadata Schemas and Related Standards.

Libraries

Because libraries collect published items that are also held within many other libraries, they were early in developing standard cataloguing formats and have been very active in metadata initiatives such as DC. The main electronic metadata standard used by libraries is MARC (Machine-Readable Cataloguing) which has been in use since the 1960s in several different versions. MARC concentrates on bibliographic items (e.g. books and journals), but has also often been used by libraries to catalogue other types of collections. Those building digital collections within a library context may want to derive their metadata from existing MARC records or develop metadata compatible with the MARC format. Or it may be that they are digitising books and so require a metadata schema suitable for describing bibliographic works.

Because MARC is such an extensive standard, the library community has developed a sub-set of elements taken from MARC called MODS (Metadata Object Description Schema). MODS is intended to be used for a variety of library purposes, uses language base tags rather than the numeric ones used by MARC and is expressed in XML. This latter development gives MODS an advantage when being used to share data between different sources and combining with other metadata standards. For example, those digitising a book might choose to use MODS to describe the book as a whole, DC to describe the individual page image files, and METS to wrap the various records together (see Structural metadata, below).

The library community is also currently developing a new content standard to govern the way data is recorded within catalogue records (similar to the CCO standard mentioned below). This will be called RDA (Resource Description and Access) and will replace a much older, pre-digital standard called the Anglo-American Cataloguing Rules (AACR).

Museums and Heritage

For UK museums, a key standard is the MDA’s (Museum Documentation Association) SPECTRUM documentation standard. SPECTRUM is more than a metadata schema. It is a guide to documenting all the procedures a museum might need to undertake in managing its collections (e.g. acquisition, cataloguing, auditing, and loans). SPECTRUM recommends several “units of information” that can be recorded to support each of these procedures, some of which are required, others recommended. 

In terms of cataloguing museum objects, SPECTRUM suggests that sometimes it will be appropriate to catalogue at a collection level; at other times, at the item level. It suggests that any catalogue record should include at least: an identity number, name of the object, number of items or parts, physical description, and details about its acquisition, location and any associated images. SPECTRUM does not prescribe particular elements for digital reproductions, so those developing museum collection management systems often use SPECTRUM as the basis for the object information and DC to record information about any associated digital images.

While SPECTRUM focuses on the description and management of heritage objects, the MIDAS standard (Monument Inventory Data Standard) concentrates on UK heritage environments. MIDAS is maintained by FISH (Forum on Information Standards in Heritage), who have developed an XML version and other tools for interoperability. It is likely that we will see some convergence or increased compatibility between SPECTRUM and MIDAS in the future.

Archives

Because of the hierarchical nature of archival resources (typically large amounts of unique materials arranged in collections and sub-collections) the archival community has adopted a different approach to cataloguing its resources to libraries. Instead of creating metadata records for individual items, archives typically create metadata records for a whole collection, breaking it down into series and item levels where these are important and an archives’ limited financial resources will enable it. We have already seen this multi-level approach to cataloguing in the SEPIADES standard (above). The main standard for archives is ISAD(G).

Like the SPECTRUM standard, ISAD(G) says which units of information should be recorded for a collection, but does not specify a particular data structure or form of encoding. An independent but closely-related standard called EAD (Encoded Archival Description) provides such an encoding, using the XML format. EAD is increasingly being used to enable archives to publish or share their archival records. It is used, for example, within the UK’s Archives Hub and the Online Archive of California (OAC). EAD includes some elements for describing digitised versions of archival materials (see its <dao>Digital Archival Object</dao> tag). Multimedia objects can be described in simple terms within an EAD record, but those using EAD may prefer to link to more detailed records described using another schema.

In 2005 the US archival community published a content standard similar to the art image community’s CCO and the library community’s RDA standards (see above). Called DACS (Describing Archives: A Content Standard), it is intended to help archivists decide how to select and format the information they put within ISAD(G), EAD, or MARC categories.

Education

The rise in electronic resources being used for specific teaching purposes has led to the requirement for metadata standards that can accompany and describe such resources. A key international standard is IEEE LOM (Learning Object Metadata). LOM was based on older metadata schemas and has been much influenced by DC. A UK application profile of the LOM, called UK LOM Core, is currently available in a draft form.

Because it deals with learning resources, LOM includes categories related to the resource’s educational use (e.g. interactivity level, typical age range, typical learning time). Another interesting category is Annotation, which provides space within the metadata record for educators to record their comments about the learning resource.

Task specific metadata schemas

The previous sections have discussed standards for describing specific types of resources (e.g. art works, photographic archives) or materials held by specific communities. In addition, some specialist schemas or related standards have been developed for particular tasks such as recording technical or preservation-related information, structuring different sets of metadata, or sharing metadata with others. We present the main standards for each below.

Technical metadata for digital still images

A standard has been developed to record technical information about raster (i.e. pixel-based) digital images.  This is referred to as Technical Metadata for Digital Still Images or NISO Z39.87, which is the code given to it by the US based National Information Standards Organization (NISO).  It takes the form of a data dictionary rather than a formal schema, listing technical elements that an organisation might want to record about a digital image. In order to make it more usable and interoperable, the Library of Congress, MARC Standards Office and the original committee responsible for its creation have developed an XML version called MIX (NISO Metadata for Images in XML), which is currently in its second version. NISO Technical Metadata is an extremely detailed standard which gives scope to record basic image information and extensive image capture and change history elements.  Those building digital image collections may want to be selective about the elements they choose from the standard (perhaps via MIX) rather than implement it in its entirety.

Preservation metadata (PREMIS)

Like NISO Technical metadata (previous section) a data dictionary has been developed listing core metadata elements that can be used to support the preservation of a digital resource. Called PREMIS, this standard was based on an international survey of practice and on previous preservation research. It was particularly influenced by the Open Archival Information System (OAIS), which provides a framework for the long-term preservation of digital (and non-digital) resources.

PREMIS recommends recording various bits of information about (1): the Intellectual Entity (i.e. the “work” itself); (2) the related digital Objects (e.g. their format or encoding); (3) any particular preservation-related Events (e.g. acquisition, conservation); (4) Agents (e.g. details of the preservation repository or rights owner); and (5) any related Rights information (e.g. conditions of use). All five sets of information are important for understanding how a resource has reached its current state and what can be done with it in the future.

The developers of PREMIS felt that the metadata for the Intellectual Entity was best supplied using a relevant descriptive metadata standard (e.g. DC, VRA Core or MODS), so PREMIS only provides elements for Objects, Events, Agents and Rights. It is not very prescriptive about how much of this information should be recorded or in what form it should be encoded, but it does provide XML encoding. Like the NISO Technical Metadata standard, it is likely that those using PREMIS will pick and choose which elements they want to use, and will use the XML version to incorporate PREMIS within their overall metadata framework, perhaps incorporating it within a METS record (see next section).

Structural metadata (METS)

In the discussion of DC (above) we said that relationships between metadata records could either be made by including references to separate but related records or by wrapping up a number of records within a larger, coordinating metadata standard. The Metadata Encoding and Transmission Standard (METS) is intended to facilitate the second approach. METS can coordinate or “package” any number of files or metadata records. Although it includes some metadata elements of its own, METS is designed to accommodate other metadata standards.

There are two ways to use other metadata with METS: (a) embed it directly within the METS record; or (b) provide a link from the METS record to an external metadata source. METS is an XML-based standard, so any metadata embedded within it is also best encoded as XML. But as we have seen, metadata standards are increasingly being provided with standard XML encodings.

Each METS record has four main sections (there are some others). These are summarised in the table below.

METS is potentially a very powerful standard and is becoming more useful as more XML-based schemas are developed and used. However there is still a lack of easy-to-use tools for generating or displaying METS records. Custom-written software is usually required to generate a METS record from a collection database and to style it for display via a Web browser. For the time being METS is most likely to be used by larger projects that are digitising complex resources, such as books or archives. This may change if off-the-shelf systems start providing support for the standard.

For information, we have produced two example METS records that package together various standards on:

• an audio file
• a video file

Interoperability (OAI-PMH)

At the beginning of this paper we said that an important reason for choosing a standard metadata schema is to be able to interoperate with other collections. While this has long been a goal of those building digital collections, it has been quite difficult to achieve in practice. There are several different approaches to interoperability:

• Cross-searching - your metadata and digital objects stay where they are, but are searched alongside other collections.
• Contribution - you physically give your metadata and objects to someone who is building a larger collection.
• Harvesting - your metadata and objects stay where they are, but you make available metadata records in a standard format for others to use in building catalogues which point to your resources.

The harvesting approach is a kind of cross between the other two. It has the advantage of opening up your collection to others while maintaining your ability to manage and maintain your digital objects and their metadata locally. OAI-PMH is increasingly being used to achieve this kind of interoperability.

OAI-PMH requires you to generate your resource discovery metadata in a standard XML format. Simple DC is required by the protocol at minimum, although any standard set of metadata can be used additionally for this purpose. These records are placed in a public space on a server and made available for others to harvest. The data can then be incorporated into the harvesting bodies’ catalogues or directories, thus making the records from your collection cross searchable with however many other datasets they choose to harvest. If using simple DC, these OAI records may represent a “dumbed-down” version of your richer metadata, but users will often have a link through to your own collection to view the digital resource itself. Once there, they will be exposed to your full metadata and can see the item in its context.

The diagram below shows a simplified top level view of the protocol in operation, with the contributor’s metadata being made available on the contributor’s server to be requested and ingested by the harvesting bodies’ catalogue.  There is no limit as to how many data-sets can be harvested in this way, and the OAI protocol therefore can enable end users to cross search many collections of metadata from one place.

This diagram is a simplified version of the one available from the National Library of Australia’s Picture Australia Technical Guide. Indeed Picture Australia is a very good current example of OAI-PMH in practice, whereby various image collections from around Australia contribute metadata data to a central place where their materials can be accessed together.

Other examples can be seen at the OAIster project at the University of Michigan, which has harvested almost 10 million OAI records from 700 institutions:

• OAIster

Application Profiles

Application Profiles have been defined as ” ... schemas which consist of data elements drawn from one or more namespaces, combined together by implementers, and optimised for a particular local application.”  In other words, it is possible to ‘mix and match’ metadata elements from across different schemas and use the resultant ‘profile’ as a means to provide more precise search and retrieval within a narrow domain, say learning resources, while maintaining DC (and other) mappings to enable basic interoperability with the world at large. Some examples from specific communities include:

• Library Application Profile (DC-Lib)
• Collection Description Application Profile (DC CD AP)
• Education Application Profile (DC Education)

And there has also been recent development in the UK to develop DC based application profiles for specific resource types (text, images and moving images) that can aid interoperability of the growing network of Institutional Repositories, these are:

• Scholarly Works Application Profile (SWAP)
• Images Application Profile
• Time Based Media Application Profile

Application Profiles are often not only concerned with the elements and vocabularies that are chosen, but also the way the metadata is encoded. They often specify a particular way of tagging and laying out a metadata record using XML encoding. This level of specification is very important if metadata records created using the profile are going to be easily interoperable.

The development of XML-based metadata schemas or application profiles is becoming increasingly common. Early metadata standards were not very prescriptive about how their categories were named or laid out (most people were just using them as fields in their databases). However as the use of XML has become more common and its potential for interoperability is being realised, XML encodings are being developed for most formal metadata schemas. See for example the recommended XML schemas for the Dublin Core.

Metadata vocabularies

This paper has concentrated on metadata schemas: the categories you use to describe and manage your digital images. However the use of standard categories will not guarantee that your collection can be efficiently searched or understood by your users. Metadata vocabulary standards will assist you in choosing specific terms to enter into those categories.

Metadata schemas frequently come with recommendations for vocabularies. VRA Core, for example, recommends that the Art and Architecture Thesaurus (AAT) is used with several of its categories. JISC Digital Media’s metadata vocabularies advice document describes several different kinds of vocabularies and provides links to many examples available via the web.

Content standards

Of course, some schema categories commend themselves more to formal vocabularies than others. While it makes good sense to draw on a thesaurus or word list to fill in a Subject or Format category, a Title or Description category will require a different approach. For these kind of categories, data entry guidelines must be devised. Some metadata schemas provide this level of guidance to their users, others don’t. Although there are some older precedents, a fairly recent trend is the development of separate content standards (e.g. CCO, RDA and DACS above). Their purpose is to provide detailed guidance on data entry to help ensure consistency and so improve interoperability.

Conceptual models

Each metadata standard mentioned above has a conceptual model which underpins it, and while not directly related to the primary objective of this paper, the notion of the conceptual model still worth some consideration. In the context of metadata, and information management in general, the aim of the ‘conceptual model’ is to provide the means of achieving an efficient structure and flow of information in a specific problem area in a given domain. This is achieved through the modelling of relationships between things or actions (concepts) that have been identified. So, for example, a museum (i.e. the domain) may have to provide a system that can catalogue its objects and manage their life-cycle (i.e. the problem area). A typical museum object will have been made in a specific place, by a specific person, may be related to other objects, may have had various conservation treatments, images captured, been on loan to various places etc. The resulting conceptual model could involve creating a series of entities developed from the concepts of: ‘object’, ‘person’, ‘place’, ‘images’ and ‘event’ and then articulate how these entities are best described (i.e. what attributes they have) and how the entities relate to one another (i.e. a person ‘makes’ an object, an image ‘contains’ an object etc.) Concept models are developed at a level of abstraction removed from the actual domain or problem area they are addressing which means that one model can underpin the whole system that eventually manages, in this case, the museums’ holdings.

Metadata schemas often acknowledge their conceptual framework (such as DC‘s one-to-one principle, or the hierarchical relationships implied in ISAD(G)). There are also attempts to provide separate, fully articulated conceptual models, which amount to metadata “world views” of given domains. For example, the CIDOC CRM (Conceptual Reference Model), which began life in the mid 1990s as an attempt to establish a model for the description of museum and cultural heritage information, is now an ISO standard which is likely to underpin many future information sharing and semantic web initiatives.  The Libraries domain has developed the Functional Requirements for Bibliographic Records (FRBR), which provides a model for the relationships between, and access and retrieval of, library holdings, primarily, though not limited to, bibliographic records. FRBR is also seeing applicability in other areas (see current work on application profiles and attempts to harmonise CRM and FRBR). Both these models are detailed in Putting Things in Order - a Directory of Metadata Schemas and Related Standards.

Conceptual models can be useful in: (1) helping make explicit some of the assumptions implicit within metadata schemas; (2) informing the evolution of existing schemas or the development of new schemas, (3) assisting in the task of mapping two different, but related, schemas, and (4) developing database and other data management systems.

Embedded metadata

As we said in the introductory paper to this series, metadata can be extracted from, or embedded within, the digital file itself.

The first part of an image file - before all the pixel data - is the “file header”. This contains information about the file itself (e.g. its format and order), but it also has some room for other data. Digital Cameras make use of this space within the TIFF and JPEG formats to write EXIF data (information about the camera and its settings). Programs like Adobe Photoshop enable users to embed descriptive metadata according to a schema called IPTC. Adobe have also developed an XML-based metadata schema called XMP, which can potentially embed a wide variety of other metadata standards within image files, including DC. More information about these standards is provided in JISC Digital Media’s Putting Things in Order - a Directory of Metadata Schemas and Related Standards.

There is some potential here for those developing digital collections to write their metadata directly into their digital files. This can be particularly useful in: (1) providing identification information, in case your image is separated from its usual context or is renamed; and (2) enabling you to record information about copyright or usage restrictions within the file.

However, there are also some problems with relying on embedded metadata: (1) it is usually very easy for someone to delete this information, either deliberately or inadvertently; (2) these standards are not supported across all common formats or accessible to all image optimisation or image management software; (3) writing data into some file formats will require re-compressing the image, which can compromise its quality (e.g. the popular JPEG format).

Conclusion

There are many considerations to take into account when choosing the metadata standard(s) that best fit your resource and your users’ needs. This paper has outlined some of these, which centre around: the type of resource you are creating; the domain you work in; the particular tasks you want to carry out; and the level to which you want your resource to complement and perhaps be searched alongside other related collections.

At one level, every resource will have its own idiosyncratic metadata needs, users and priorities, however, hopefully this paper has shown that this need not be at the expense of using common standards. Indeed to ensure a managed resource that can engage users effectively and enjoy a degree of longevity, conformity to formal metadata standards at some level - more often than not adapted to fit your needs - is essential.

To recap, some of the factors likely to influence your decisions are:

• Your users and their needs - what kind of information do they require and expect?
• Your own needs as a collection manager - what information do you require to manage, deliver and preserve your collection?
• Your community’s approach to metadata - are there clear standards being used by similar collections?
• Your legacy metadata - what metadata already exists, what form does it take?
• Existing systems - does the metadata need to work well within particular systems (e.g. library catalogues, VLEs)?
• Your resources - how much time can you allocate to cataloguing; can you really afford to fill in dozens of categories or do you need something simpler?
• The level of technical expertise available to you
• Interoperability - how important is it that your collection works alongside other collections?
• The future development of your collection - e.g. do you expect it to grow to include other formats or subjects?

Last updated: 07 January 2010
Published in: Managing your digital resources
Tags: delivery | digital collections | digital preservation | metadata | standards

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An Introduction to Metadata

Last updated: 07 January 2010
Published in: Managing your digital resources
Tags: business & community engagement | metadata

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Summary

This is the first in a series of advice documents about metadata. In general the documents are aimed at those developing managed and sharable digital collections and are of use to those creating still image, moving image or audio collections. This first document defines metadata and introduces some of the key themes and issues that are dealt with in more depth later on.

Introduction

This first document defines metadata and introduces some of the key themes and issues that are dealt with in more depth later on. The full list of the other advice documents in the series is:

• Metadata and Digital Images
• Metadata and Audio Resources
• Metadata and Digital Video
• Metadata Standards and Interoperability
• Putting Things in Order: a Directory of Metadata Schemas and Related Standards
• Controlling your Language: a Directory of Metadata Vocabularies
• Approaches to Describing Images

What is metadata?

Metadata is often defined as ‘data about data’ or ‘information about information’. In the digital world, metadata is usually structured textual information that describes something about the creation, content, or context of an individual file or collection of many digital files.

Metadata might take the form of controlled terminology, carefully constructed or chosen from formal lists and entered into pre-established categories. Or it might be simply a free text description or set of keywords used to annotate or ‘tag’ an image. It might describe something objective and straightforward, such as the file size of the digital file; or something much more complex, such as the subject matter of the resource or legal rights associated with its use. Metadata is often held within databases, but it can take other forms - it can just as easily be found embedded within the digital file itself.  In short, metadata provides the means for us to describe our digital resources in a structured way that enables us to share those resources with other people and machines.

Selective

Metadata invariably offers a selective or simplified description of a resource. The Oxford English Dictionary defines metadata as “data that operates at a higher level of abstraction”. If “a picture paints a thousand words” (or more!) it is clear that our text-based descriptions will only ever partially capture the information or meanings held within a digital resource - let alone all the other information that might be associated with it (e.g. the history of its creation, its relationship to other resources, or possible uses to which it might be put). The challenge for those applying metadata to a digital collection is to work out which information is going to be the most important and useful to record.

Structured

Metadata is usually structured in some way. Rather than randomly associating terms with the digital file, it is common to use a set of generic categories (e.g. ‘Creator’, ‘Title’, ‘Subject’) and then assign specific terms within those categories (e.g. ‘Creator: Leonardo da Vinci’, ‘Title: Mona Lisa’, ‘Subject: woman’). The example below relates to still image metadata.

Image: Wikipedia Commons	Metadata schema categories	Metadata vocabulary terms
	Creator	Leonardo da Vinci
	Title	Mona Lisa
	Subject	woman, portrait, Renaissance…
	...etc

This approach has several advantages:

• It make it easier to create the metadata, since the categories tell the cataloguer which information needs to be collected and recorded
• It makes it easier to understand the metadata, making it clear to a user, for example, that it is Leonardo who has created this image rather than Mona Lisa!
• It makes it easier to retrieve the image in a search, since the search query can be much more specific, targeting relevant categories rather than searching across all of the metadata
• It also makes it easier to share the image and its metadata with other image collections - as long as common categories and terminologies have been used

Sometimes metadata categories are referred to as metadata ‘elements’ or ‘units’ and the full set of categories used to describe a resource are called a metadata ‘schema’, ‘data structure’ or ‘format’. Each of these labels can be problematic, since they also have other meanings. We will generally use the phrase ‘metadata schema’ in these advice documents, but the reader should be aware that this phrase is sometimes used more narrowly to refer to a particular way of encoding metadata categories within the XML (Extensible Mark-up Language) format (we will say more on XML later).

Another phrase you will often find used in these advice documents (and elsewhere) is “controlled vocabularies”. This is used where the specific terminology used within a metadata category has been drawn from a pre-defined list (e.g. thesauri) or has been constructed according to a standard set of rules (e.g. “enter the creator name in this form: ‘Surname, Forenames’”). The advice documents on metadata schemas and related standards and metadata vocabularies provide more information on these topics.

Different levels and layers

Metadata might focus on describing different levels of a digital resource. Although we will generally want to describe individual resources (e.g. a photo, a moving image or an audio file), sometimes we may prefer to describe aggregations of resources (e.g. a photo album, an online learning resource or a music album). Or perhaps we might wish to describe just a part of a larger whole (e.g. an illustration found within a published book, a particular scene from a moving image file or a single track of music from an audio file). Those developing metadata standards have approached this challenge in different ways. Some have created separate metadata records to describe individual ‘things’ (e.g. collection, single item, part of an item) and then made links within the metadata record to related files and metadata records, e.g. the Dublin Core (DC) schema. Some have created complex metadata schemas that are capable of describing different levels within a single metadata record, e.g. the SEPIADES schema. Others use different kinds of metadata to describe the various levels of a complex resource and then tie them together using special metadata schemas that are intended to structure and coordinate other metadata, e.g. the METS schema (Metadata Encoding and Transmission Standard).

As well as being focused on different levels, metadata might describe different ‘layers’ of content within the digital resource. Take again the example of Leonardo’s Mona Lisa. In this case there might be (a) an original art work (the painting), (b) a photographic reproduction of that art work (a slide), and (c) a digital representation of that work (a digital file). The table below shows how the metadata might differ according to the different ‘content layer’ being described.

			010010100101 010010100101 001010101010 100001001010 101010101001 010100101010 011001010101
	Original image	Slide image	Digital image
Creator	Leonardo da Vinci	Jane Smith [Photographer]	John Brown [Scanning Technician]
Format	Painting	Photographic transparency	JPEG image
Location	Louvre Museum	University slide collection	A:\images\0023.jpg
...etc

The challenge for those creating metadata is to decide which layers need to be described, how much detail to go into for each, and how the resulting metadata will be organised. Although, in the example above, Leonardo, Jane and John have all contributed to the creation of the final digital resource, you are likely to mislead users of your collection if you put all of their names in one field in your database. As with the different levels, metadata schemas tackle this problem in different ways. Some will create sub-categories (e.g. Creator_OriginalWork; Creator_SurrogateImage); others, separate categories (e.g. Artist; Photographer; Scanning Technician); others, completely separate records for each layer.

Different purposes

Metadata can also serve different purposes. It might be used to help us to find the resource (often termed ‘resource discovery’ metadata), or might tell us what it is (descriptive metadata). It might tell us where the resource has come from, who owns it and how it can be used (provenance and rights metadata). It might describe how the digital resource was created (technical metadata), how it is managed (administrative metadata) and how it can be kept into the future (preservation metadata). Or it might, as mentioned above, help us to relate this digital resource with other resources (structural metadata).

These are not discrete sets of metadata: there is obviously a considerable overlap. For example, descriptive metadata (e.g. subject of image) will also be very important in searching and retrieving the image (resource discovery); while metadata relating to the creation of the resource (e.g. filename and format) will clearly also be vital in managing and preserving it.

However, while there are no clear divisions, it can be convenient to use labels like “descriptive” or “administrative” to characterise the different metadata standards in existence. Some standards tend to be much more focused on resource description (e.g. Dublin Core), while others include a larger proportion of administrative categories (e.g. Categories for the Description of Works of Art). There have also been some attempts to create standards that are focused on particular purposes (e.g. NISO Technical Metadata, PREMIS Preservation metadata).

These distinctions are also useful to keep in mind when you are developing your own metadata framework and delivering your collection. What activities do you need to support? What particular metadata categories will you need to include to support those activities? The broad distinction between “descriptive metadata” and “administrative metadata” is a useful reminder that some of your metadata is going to be particularly aimed at the end users of your digital collection and other metadata will be primarily for your own use and management of the collection. Descriptive metadata is likely to be searched and displayed within a public interface, while much of the administrative metadata will need to be hidden from public display (e.g. location of your master files).

Those who have written about metadata have often differed in the broad categories or types of metadata they identify. In this and other advice documents, we will generally talk about four categories (below), but the reader must always remember that these are to some extent artificial and overlapping:

• Descriptive metadata - used to find, identify and understand a resource
• Administrative metadata - used to manage the creation, use and preservation of the resource (includes technical and preservation metadata)
• Structural metadata - used to record and facilitate relationships between or within digital resources
• Use metadata - metadata collected from or about the users themselves (e.g. user annotations, number of people accessing a particular resource)

Different communities and users

Metadata does not exist in a vacuum. As the previous paragraphs have indicated, it serves particular purposes and particular groups of users. We’ve just distinguished the end users of the collection from those managing the collection (who are also “users”). But even among these groups there will often be different kinds of users with different needs. In developing a metadata framework for your collection it is important that you identify all of these users and needs. It’s best to ask your users what information they need rather than make assumptions.

Digital collections are often based within particular ‘communities’, for example: libraries, archives, museums, educators. Many of the formal metadata standards currently in use have been developed within such communities. This has advantages and disadvantages. It means that these standards are generally good at supporting the needs of that community. However, they can also incorporate old-fashioned or ‘legacy’ approaches that may have worked well in a non-digital environment, but are not as practical or useful in the digital world. If your collection is firmly based within a particular community, it probably makes sense to adopt the metadata standards commonly used within that community - if they exist.

However it is important to realise that the approaches and biases that community-based standards encode within their metadata may not be suitable for digital collections that span different kinds of communities or physical collections. In these cases, it will usually be necessary to take a more generic approach, which often means some kind of compromise.

As this section has indicated, metadata can take many different forms. It can focus on different aspects of the digital assets (layers and levels), serve different purposes, users, and communities, and be structured in different ways. Those developing a metadata framework for a digital collection will face several challenges and will need to decide on the most suitable approaches to overcoming them.

Where does metadata come from?

Metadata relating to a digital resource can come from one of two sources: (a) it can be automatically derived from the digital resource itself, or (b) can be created and associated with a resource by human beings.

The first kind of metadata might be called intrinsic or implicit metadata. Examples of this include file formats, resolution, bit-depth, or frame-rate. File formats typically encode this sort of information within the header (the first section) of the digital file. If an image has been created by a digital camera, it is likely that the camera has also written a certain amount of information about the digital capture into the file header, such as the camera make and model, its settings, and the date the photograph was taken (this makes use of the EXIF standard)

Most implicit metadata is technical in nature and is generally - although not always - of more use to those administering the collection rather than those using it. While most implicit metadata is derived from the file itself, a certain amount could also be derived from its context (e.g. its location within directories/folders or on servers). In developing a digital collection it may be useful to extract some implicit metadata and hold it separately within a database for the purposes of retrieval, quality control, or digital preservation. Typically, though, much implicit metadata is left untouched within the file.

The second kind of metadata might be called extrinsic or explicit metadata. Because this is created by humans, it is the most difficult and expensive metadata to create. But it is also usually the most important - especially to the end user. The advice documents in this series are mostly concerned with creating and managing explicit metadata.

Although explicit metadata must be created by humans, it need not all be created by those building and cataloguing a digital collection. It is very likely that there is some pre-existing legacy metadata that can be exploited (even if it is just a scrawled inscription on the back of a photograph, film can or audio cassette). Or it might be possible to get your collection users to add to the metadata in a semi-controlled way way (via tags or annotations).

Those developing digital collections will need to make decisions about what implicit metadata should be extracted and what explicit metadata needs to be gathered or created to support the collection and its users. Usually resource limitations will play a role in these decisions. Some collections can afford to spend hours creating metadata for each resource; others less so. Some digital asset management systems are able to automatically extract implicit metadata from a digital file; many cannot and will rely on the cataloguer using other tools to discover this information manually.

Where is metadata kept?

Metadata for digital collections can be held in several different places: (a) within the digital file; (b) within a database; (c) in a separate XML-encoded file; or (d) all of the above at once. These options are briefly described in the next few paragraphs.

As the earlier discussion of implicit metadata has indicated, there is already a certain amount of metadata held within a digital file. Some of this might be extracted for use outside of the digital asset. In addition to extracting metadata, it is possible to embed some metadata within the digital asset. Those embedding metadata into still image files can make use of the well-supported IPTC standard (originally developed to enable photojournalists to “wire” their images) or the eXstensible Metadata Platform (XMP) standard.

Most people developing digital collections will make use of a database to hold their metadata. Other advice documents in this section of JISC Digital Media’s Advice documentation provide advice on digital asset management systems.

Increasingly, XML is being used as a way of encoding metadata. XML is related to HTML (the original coding used on the World Wide Web). While the HTML tags are primarily focused on presentation (e.g. <b>Bold</b>), XML tags are used to indicate meaning (e.g. <organisationName>JISC Digital Media</organisationName>). This approach lends itself well to expressing metadata, enabling metadata schema categories to be turned into tags and wrapped around specific terms, as the simplified example below shows.

Image: Wikipedia Commons

<image record>   <original work>       <format>painting</format>       <creator>Leonardo da       Vinci</creator>   </original work>   <reproduction>       <format>photographic       transparency</format>       <creator>Jane       Smith</creator>   </reproduction>   <reproduction>       <format>JPEG       image</format>       <creator>John       Brown</creator>   </reproduction> </image record>

Most digital collections still store their metadata in databases, but might write a program to take the metadata from their database and encode it in an XML format for sharing with others.

Increasingly digital collections are making use of all three approaches: writing metadata into their digital files, storing and delivering their metadata via a database system, and encoding their metadata as XML for certain purposes, such as sharing their data with other collections. This trend is likely to continue, especially as the newer file formats provide better support for metadata within the file; systems become more capable of importing and exporting XML; and standard XML encodings are developed for existing metadata standards.

Conclusion

This advice document has provided an introduction to metadata and an overview of some of the issues involved in developing a metadata framework for a digital collection. The other advice documents in this series explore these issues in more depth and provide practical advice.

There are other good overviews of metadata available online. JISC Digital Media would particularly recommend the following:

• Understanding Metadata (NISO, 2004 - PDF file)
  
• Introduction to Metadata (Getty)
• Metadata Directory (UKOLN, 2005)

Last updated: 07 January 2010
Published in: Managing your digital resources
Tags: business & community engagement | metadata

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Using Digital Media with Blackboard

Last updated: 11 December 2009
Published in: Managing your digital resources
Tags: e-learning | vle

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Summary

This advice document aims to introduce the Blackboard virtual learning environment (VLE) and how you can use digital media to support your Blackboard course design, content, and delivery.  We will be referring to the term digital media as: still images, moving image and audio. Each may be used in conjunction with written learning material.

Background

Blackboard is a proprietary Virtual Learning Environment (VLE) widely used by further and higher education (FE/HE) institutions across the globe. As a VLE it was conceived to enable and support online learning. It consists of manageable areas for structuring course content, administration and tools to support asynchronous and synchronous learning. It requires the internet and is used for:

• Face-to-face learning Production of material / activities to be used during face-to-face teaching sessions.
• Blended learning Material and/or activities from Blackboard are integrated into the face-to-face sessions and vice-versa.
• Distance learning Where teaching is only conducted via the internet using online tools such as Blackboard and other web services.

To ensure everything within Blackboard is secure it uses authenticated access to a course based on various permissions set by staff administrators. It has a comprehensive set of tools that facilitate learning using a range of learning modes including communication, discussion, access to content and assessment.  Many of these tools support the three digital media this document is concerned with.

Detailed information about VLE’s in general can be found in our Use of VLEs with Digital Media advice document.

Using digital media in Blackboard

Blackboard acts as a secure shell that supports different types of content and course management.  Digital media learning objects can be embedded and/or linked to, enabling the enhancement of course content.

Understanding how digital media fits into your course is as much about understanding what you are trying to achieve (learning objectives) as it is about the actual file type. The digital media itself may form core activities that support a range of learning including peer review, demonstrations and submission or it may provide additional learning objectives.

ntil fairly recently most VLE content was predominately text-based. However, this is now changing due to a number of factors:

• Increase in availability of affordable hardware to capture still image, moving image and audio
• Increase in the use of a blended learning approach
• Digital media is now widely recognised as having benefits to learning
• User-generated content is rapidly growing and available for re-use
• Learner engagement can be increased by appealing to different learning styles within the student cohort
• It is now easier than ever to embed content (for example Media players for audio/video, APIs and RSS to push/pull content)
• Web-based software/services are constantly emerging which provide powerful features/tools that are often free, that support the use and re-use of digital media
• Increase in availability of access (increase of broadband internet / mobile devices)
• Experimentation with digital media is more common
• Demand from the learner community has shifted how teaching can/should be carried out using digital media resources.

These factors have led many course designers to believe that a shift for course design towards a more learner-centred approach is essential. Many course designers are facilitating different techniques, technology and media to enable learning in new ways. The learner is able to use different media to support their learning at a time that suits them with tailored learning material best suited to the situation.

Learners themselves are frequently creators and users of digital media. This has led some teaching staff to experiment with the potential benefits of using digital media in conjunction with Blackboard to support formal/informal learning.

Digital media can be used to add engagement as part of an activity. Depending on the task, a suitable media type can be chosen and an action carried out that best suits the media and activity.

Some types of learning and possible learner behaviour are:

• Formal learning (face to face dissemination, critique and sharing)
• Informal learning (learner may share ideas, make associations)
• Group activity (Create, evaluate)
• Individual reflection (Gain understanding, testing, evaluation)

Each media type can be used in the learning situations given above, this demonstrates that there is more than one way to plan and execute activities that use digital media and the need for careful planning.

How digital media can be used

The Still image

Still images have been used for many years and their continued popularity can be explained by:

• Ease of creation – Either conversion to digital or self-produced
• Availability - If you do not have existing images many outlets produce free/cheap to use images
• Ease of use – simple to embed, position and alter.

Still images are a great way to visually represent key concepts support text-based material.

Here are some ways you can choose to use images in an online environment:

• A well sized image that supports text-based content around it (visual explanation)
• Add a link to a larger/higher quality version if necessary (file may be stored elsewhere on page or externally)
• Create small thumbnails of images to link to a larger version (file may be stored elsewhere on page or externally)
• Add a descriptive title or description so that it is immediately contextualised for learners
• Add ALT tag (alternative information) for an image to support accessibility
• Create an image with clickable parts (an image map) to access different information (requires HTML knowledge)

Video

Video can be used in a number of ways for a diverse set of reasons in order to create motivating, memorable and inclusive learning experiences. However, watching a video can also be a passive experience and so teaching methods must be used which instead turn it into a springboard for learner action and interaction. Using embedded video, so that the video is within the page, reduces barriers to accessing the content. See our advice document Using Video in Teaching and Learning.

Audio

Audio is now commonly used to supplement face to face sessions largely in part to the fact that simple to use software, affordable hardware and online support material are now available. There are opportunities for assessment that are beginning to show signs of taking off such as oral feedback.  Common uses of audio include:

• Capturing the teaching session in its entirety
• Providing edited highlights of a teaching session
• Making a guest speaker’s (speeches/lecture/presentation) available

Less commonly used but with potential is recording for:

• Peer review: both teaching staff and learners may benefit from sharing recorded submissions
• Accessibility: recording audio will improve accessibility for some learners
• Assessment submission: some teaching staff are now allowing submission via recorded files and are also returning feedback in the same way.

See our advice document on Audio via Blackboard.

Our sister service JISC TechDIS has an accessibility and inclusion focus and have written their own advice on Using sound effectively.

Where media can be used in Blackboard

Digital media can be used within most of the tools and features of your course.

• Media can be uploaded as a stand-alone resource or organised into folders via the “edit view” of any section
• By attaching existing documents that contain media (e.g. Microsoft Word, PowerPoint, Adobe PDF)
• Throughout Blackboard including: Discussion Boards; the Virtual Classroom; Quizzes; Surveys and Assignments
• Anywhere in Blackboard where you use HTML
• Linked to or embedded from external sources (to Blackboard)
• Some versions/setups of Blackboard allow the use of RSS feeds that push content out to other areas of Blackboard or external services/devices such as podcasts

Content and file management considerations

How does Blackboard manage your media content?

When you have logged into Blackboard and have been granted ‘Instructor’ access to your course by your VLE administrator, you can begin structuring course content by adding course sections, tools, resources or uploading documents.  There are two views when using Blackboard: Display view, which learners view and Edit view for administrators to add, edit and remove features.

Developing your course structure within Blackboard takes place by creating what Blackboard calls content areas.

A Blackboard content area contains a subset of content types such as folders and is therefore a way of organising content.

Folders are one of the most common ways used to organise files, and are often used to act as sections themselves. E.g. a folder called Module 1, 2 , 3 etc.

Media organisation tips

It is good practice to be organised with all your media so that you know where they all are! This means not only how you name a file, but being logical in your methods of storing resources on your local computer, as well as when uploading into Blackboard. For example, if you use a collection of audio files for module 1, then on your local computer also store these files in a folder called “module 1 audio”. A very common support call, for those who provide technical support in your Blackboard, relate to poorly organised modules and courses.

For those with the Blackboard Content Collection feature this is a very helpful tool for organising all of your media. One of its biggest strengths is that content stored here can be used in multiple locations in Blackboard and updating it once will update all instances.

Intellectual property right issues (IPR)

Copyright is an intellectual property right and arises automatically whenever a work is created. It gives the owner of the copyright the right to exploit their work or control its use.

If using other people’s digital media it is important to be aware of copyright issues and respect the creator’s view. Therefore when a piece of digital media is made available online or published through a VLE, you may need to clear copyright.

Here are a few pointers to consider when selecting digital media for use in a VLE:

• Copyright is something to take seriously but it need not be an obstacle
• When finding digital media online you will need permission to reproduce them in your materials, you should always carefully read the terms and conditions (if made explicit)
• If you make your own digital media to support your teaching your employer will almost certainly hold the copyright
• Some FE and HE institutions may be able to use a CLA (Copyright Licensing Agency) scanning license to produce images.
• Asking permission seems like a chore but it may bring unexpected reward such as a higher quality version
• You must obtain clearance from the rights holder(s) of third party material that you use within your material.

If you have been granted permission to use a digital media resource it is advisable to put clear copyright information next it. It is also important that you keep a copy of the permission given.

Further information on copyright is in our advice documents Copyright and Digital Images and a href=“http://www.jiscdigitalmedia.ac.uk/stillimages/advice/roles-and-responsibilities-building-digital-image-collections/”>Roles and responsibilities building digital image collections

Conclusions

Blackboard provides the capacity to support the teaching and learning experience. The use of appropriate digital media can further enhance the learner experience by providing additional support mechanisms, interactive activities and engaging content. Digital media learning objects can be used in isolation or form part of a wider set of activities used in a range of ways.

It should be noted that in order to successfully utilise digital media within Blackboard it must be factored into the wider module/course plan. Too often there are attempts to use digital media as a magic bullet to increase uptake of the VLE and it fails. The pedagogical reasoning behind what and how learners are doing tasks surpasses everything and the use of the technology should feed into the plan not attempt to carry it. The usability of the course design also affects usage and you should seek to build a well designed course.

Don’t be afraid to experiment with ideas for supporting your learners with digital media in Blackboard. If you’re not sure where to start ask your learners what they think of your existing provision and work from there. As ever JISC Digital Media is available to support you through our helpdesk and online surgeries.

Last updated: 11 December 2009
Published in: Managing your digital resources
Tags: e-learning | vle

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Using Digital Media in Moodle

Last updated: 10 December 2009
Published in: Managing your digital resources
Tags: e-learning | teaching | vle

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Summary

This advice document is intended to provide an understanding of how digital media can be used in the Moodle VLE to support teaching and learning. We will be referring to the term digital media as: still images, moving image and audio. Each may be used in conjunction with written learning material.

Moodle is a free to use open-source Virtual Learning Environment (VLE). It has been created to help educators create effective online learning communities. Moodle enables a forum for discussion, learning and integration both inside and outside of the classroom for curriculum delivery.

Detailed information about VLE’s in general can be found in our Use of VLEs with Digital Media advice document.

Digital media learning objects can be used to enhance and facilitate learning by building upon ideas, concepts and tasks, using a variety of approaches that best suit the situation.

Using digital media in carefully designed teaching activities can make the learning experience engaging and deeper. This is ‘e-learning’.

The JISC define e-learning as ‘learning facilitated and supported [learning] through the use of information and communications technology (ICT)’.

Using digital media in Moodle

Until recently most VLE content was predominately text-based. However, this is now changing due to a number of factors:

• Increase of affordable hardware to capture still image, moving image and audio
• Increase in the use of a blended learning approach
• Digital media is now widely recognised as having benefits to learning
• User-generated content is rapidly growing and available for re-use
• Learner engagement can be increased by appealing to different learning styles within the student cohort
• It is now easier than ever to embed content (Media players for audio/video, APIs and RSS to push/pull content etc)
• Web-based software/services are constantly emerging which provide powerful features/tools that are often free, that support the use and re-use of digital media
• Increase in availability of access (increase of broadband internet / mobile devices)
• Experimentation with digital media is more common
• Demand from the learner community has shifted how teaching can/should be carried out using digital media resources.

This increase has helped shift course design towards a more learner-centred approach. Many course designers are facilitating different techniques, technology and media to enable learning in new ways. The learner is able to use different media to support their learning at a time that suits them with tailored learning material best suited to the situation.

As well as consumers of digital media, learners are now more frequently creators of digital media. This has led to some teaching staff experimenting with the potential benefits of using digital media more extensively with Moodle to support formal/informal learning and teaching.

For example the use of audio by teaching staff to supplement face to face sessions has grown in popularity. This is often referred to as a podcast. There are opportunities for assessment that are beginning to show signs of taking off such as oral feedback.

Just to note, individual components are termed ‘learning objects’ and where possible should be re-usable.

How digital media can be used

Still images

Still images have been used for many years and their continued popularity can be explained by:

• Ease of creation – Either conversion to digital or self-produced
• availability - If you do not have existing images many outlets produce free/cheap to use images
• ease of use – simple to embed, position and alter.

Still images are a great way to visually represent key concepts explained in text-based material.

Here are some ways you can choose to use images in an online environment:

• A well sized image that supports text-based content around it (visual explanation)
• Add a link to a larger/higher quality version if necessary (file may be stored elsewhere on page or externally)
• Create small thumbnails of images to link to a larger version (file may be stored elsewhere on page or externally)
• Add a descriptive title or description so that it is immediately contextualised for learners
• Add ALT tag (alternative information) for an image to support accessibility
• Create an image with clickable parts (an image map) to access different information (requires HTML knowledge)

Video

Video can be used in a number of ways for a diverse set of reasons in order to create motivating, memorable and inclusive learning experiences. However, watching a video can also be a passive experience and so teaching methods must be used which instead turn it into a springboard for learner action and interaction. Using embedded video, so that the video is within the page, reduces barriers to accessing the content.

See our advice document on Using Video in Teaching and Learning.

Audio

Audio is now commonly used to supplement face to face sessions largely in part to the fact that simple to use software, affordable hardware and online support material are now available. There are opportunities for assessment that are beginning to show signs of taking off such as oral feedback.  Common uses of audio include:

• Capturing the teaching session in its entirety
• Providing edited highlights of a teaching session
• Making a guest speaker’s (speeches/lecture/presentation) available

Less commonly used but with potential is recording for:

• Peer review: both teaching staff and learners may benefit from sharing recorded submissions
• Accessibility: recording audio will improve accessibility for some learners
• Assessment submission: some teaching staff are now allowing submission via recorded files and are also returning feedback in the same way.

See our advice document on Audio via Blackboard. Our sister service JISC TechDIS has an accessibility and inclusion focus and have written their own advice on Using sound effectively.

Tip

It is good practice to be organised with all of your media so that you know what and where they are! This means not only how you name them, but by being logical in your methods of storing digital media resources on your local computer, as well as when uploading into Moodle.

IPR issues

Copyright is an intellectual property right and arises automatically whenever a work is created. It gives the owner of the copyright the right to exploit their work or control its use.

If using other people’s digital media it is important to be aware of copyright issues and respect the creator’s view. Therefore when a piece of digital media is made available online or published through a VLE, you may need to clear copyright.

Here are a few pointers to consider when selecting digital media for use in a VLE:

• Copyright is something to take seriously but it need not be an obstacle
• When finding digital media online you will need permission to reproduce them in your materials, you should always carefully read the terms and conditions (if made explicit)
• If you make your own digital media your employer will almost certainly hold the copyright
• Some FE and HE institutions may be able to use a CLA (Copyright Licensing Agency) scanning license to produce images.
• Asking permission seems like a chore but it may bring unexpected reward such as a higher quality version
• You must obtain clearance from the rights holder(s) of third party material that you use within your material. For example if you have a recorded video lecture which includes the use of third party video, you must seek permission.

If you have been granted permission to use a digital media resource it is advisable to put clear copyright information next it. It is also important that you keep a copy of the permission given.

Further info on copyright can be found on our advice document Copyright and Digital Images.

Conclusion

One of the principles and strengths of Moodle is its ability to support pedagogy. Moodle is able to act as “A dimension relating to flexibility and a dimension relating to an educational model about learning activities.”

Flexible learning in a digital world, collis and Moonen, p86

Moodle has the tools and ability to support a range of tools and media as mentioned throughout this document. Carefully planned learning material and digital media in conjunction with Moodle will support learners and the teaching process.

The use of digital media will be appealing to learners and can enhance understanding of complex concepts.

Finally, there are many ways in which to use digital media, if you get stuck for ideas try searching on the web for some examples that many institutions are sharing.

JISC Digital Media would like to thank the ULCC (University of London Computer Centre) and JISC RSC (Regional Support Centre) for London for their expert Moodle support and guidance in developing this document.

Last updated: 10 December 2009
Published in: Managing your digital resources
Tags: e-learning | teaching | vle

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File Formats and Compression

Last updated: 03 December 2009
Published in: Digitising analogue media | Managing your digital resources | Finding and using digital media
Tags: compression | digital collections | file formats

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Summary

This document looks at the theory of file formats and the common methods of data compression.

Contents

• Introduction
• Compression
• Open vs. proprietary
• Additional functionality
• Digital still image formats
• Digital video formats
• Digital audio formats

Introduction

Put simply, file formats are orderly sequences of data used to encode digital information for storage or exchange. They are like written languages, with their own peculiar rules or grammars. Although they are structured in different ways, digital media files generally begin with an introductory ‘header’ section followed by a ‘body’, which contains most of the data. In time-based media files this structure is often described as ‘wrapper’ format (the envelope that holds various elements together such as video, audio and related metadata) and ‘codec’ (COmpression-DECompression algorithm) which is the language used to encode the actual media content.

It is particularly important to keep in mind the distinction between file format and type of compression used within it, because they can sometimes become confused.

File names end with an extension or suffix (generally 3 letters, like .avi, .wav or .tif), which help computer programs to recognise them. Older Macintosh systems identified files in a different way, using resource forks and 4-letter codes written into the file.

Media files can be unrealistically large and compression is a way of encoding a file’s data more concisely or efficiently - squeezing or squashing the file, as the term suggests. A compression algorithm is simply a finite series of steps required to perform a given task (in this case reducing file size). A compression algorithm can either be ‘lossy’: information is discarded in order to reduce file size and/or bandwidth or ‘lossless’: no information is irreversibly discarded.

There are other distinctions that are important when considering digital media file formats: such as open- versus proprietary- file formats. These are discussed below.

Compression

As mentioned above, digital media files can be very large. It can be useful or necessary to compress them for ease of storage or delivery. However, while compression can save space or assist delivery, it can slow or delay the opening of the file, since it must be decompressed when accessed. Some forms of compression will also compromise the ‘quality’ of the file’s content.

Digital compression is a complicated science. This section offers a non-technical introduction. If it still seems a little complicated, don’t worry. The most important distinction to grasp is that of ‘lossless’ and ‘lossy’ (see below).

Two strategies: Redundancy and irrelevancy

Compression relies on two main strategies: getting rid of redundant information (‘redundancy reduction’) and getting rid of irrelevant information (‘irrelevancy reduction’).

Redundancy reduction is often used during lossless encoding. It looks for patterns and repetitions that can be expressed more efficiently. If, for example, there are 25 values all the same, it is clearly better to record the information once and state that the next 24 values are all the same, than to record each value separately. This particular example is known as run-length encoding (RLE).

Irrelevancy reduction aims to remove or alter information that makes little or no difference to the perception of the file’s content. This usually happens prior to the encoding and involves an irreversible ‘lossy’ transformation of the content. Some of a video’s colour information, for example, can be safely simplified without being perceptible to the human eye. However, when carried to extreme this sort of compression becomes obvious and compromises quality.

Lossless and lossy

Lossless compressions are generally based on redundancy reduction and typically concentrate on more efficient ways of encoding data. The key point to grasp about lossless compression is that no information is irretrievably lost in the process. The common .zip format is an example of lossless compression, if used to ‘zip’ a collection of text documents, the exact same documents will be reconstructed once ‘unzipped’

Lossy compressions are based on irrelevancy reduction strategies but will usually also employ some redundancy strategies. Lossy compressions transform and simplify the media information in a way that gives much larger reductions in file size than lossless compressions. A typical lossless compression can be expected to cut file sizes down to three quarters or two thirds of the original - perhaps even by half, if very efficient. In contrast, a lossy compression can reduce the file size to as little as 1% of the original, although anything less than 10% is likely to distort the file’s content. The trade off, however, is that a lossy compression is by definition irreversible - it permanently disposes of information.

Irrelevancy strategy is based on the characteristics of human perception. Some information is more easily perceived and therefore more important than other information (brightness rather than colour in the visual realm, inaudible frequencies over audible ones in the audio realm).

Some digital video compressors such as MPEG-2, have an extra trick up their sleeve, as well as this simplifying of visual data in each frame of video (intraframe compression), simplifying also occurs across frames (interframe compression). So if a character remains stationary across several frames, the pixels making up the character will no be ‘refreshed’ between every frame. Instead they will remain stationary until the character moves again. In effect that portion of the video becomes a static digital photograph until a change is required. This tactic allows lossy video codecs to be more efficient.

Certain audio data compression techniques uses intelligent approaches based on models of human listening and the content of the audio file. Data relating to frequencies which are either minimally present (or not at all present) within the audio file, or those that the human ear is not particularly responsive to, are removed using mathematical algorithms. This reduction of audible content becomes increasingly noticeable when listening to highly compressed audio files, such as MP3 files with a low bit rate, where the sonic qualities are drastically altered through loss of more information at more and more frequencies.

Let’s look at the relatively simple example of the lossy digital image compressor: JPEG. JPEG makes use of a mathematical transformation known as the Discrete Cosine Transform (DCT) to shift the image’s colour values into a mode that can be more efficiently compressed and coded. The Discrete Cosine Transformation is not in itself lossy, but the next step in the compression process, known as quantisation, simplifies and rounds the colour values before they are encoded, throwing away real information. This is where the JPEG quality slider operates - it governs how much simplification occurs.

The diagram below shows the key steps in a lossy image compression. These steps are reversed when the image is displayed (decompressed). In contrast, a lossless compression will usually just have the encoding/decoding step.

Figure 1: Steps in a typical lossy image compression

JPEG compresses small 8x8 pixel blocks of the image at a time, working from top left to bottom right. Because the simplification (quantisation) of each 8x8 (64 pixel) block is done independently, at a high compression (i.e. low quality) the boundaries between the blocks will begin to show, causing the ‘blockiness’ or ‘blocking artefacts’ often observed in JPEG images. This is illustrated below.

Figure 2: JPEG without compression

These two sets of images illustrate how the processing of 8x8 pixel blocks can visibly distort an image at high JPEG compression. Each image is shown full size and enlarged 8 and 16 times. The image in the upper row is uncompressed, while the one below has had maximum JPEG compression applied (i.e. lowest quality). The blocking is a little difficult to see in the full sized image, below, but becomes quite evident as the image is viewed more closely. While both images begin to ‘pixelate’ (i.e. display their pixels) as they are enlarged, the JPEG compressed image additionally shows the edges - and the distorting effects - of its 8x8 pixel blocks.

Figure 3: JPEG maximum compression

Because they are prepared to throw information away, lossy approaches will always be able to achieve a much greater compression than lossless approaches. This makes them most suitable for situations where size is more crucial than quality, for example, streaming or downloading via the Internet. Where quality is valued more, or file size is not an issue, lossless compressions - or no compression at all - will be preferable.

Wavelet compression

Wavelet compression is a special type of compression that has been around for some time, but only in recent years has it been adopted in digital media compression. It is used within proprietary formats like MrSID and in the JPEG 2000 format (potential successor to the current JPEG) and is used for compressing both still images and digital video.

Instead of treating the image as sets of numbers (e.g. pixel values) to be processed, the wavelet transform regards the image as a signal or wave. It organises the image information into a continuous wave (typically with many peaks and dips) and centres this on zero. It records the distances from this zero line to points along the wave and then takes the average between adjacent points to produce a simplified version of the wave - in effect, it reduces the image’s resolution or detail by half. The averages are then averaged again, and so on, producing progressively simpler waves. This process is known as ‘decomposition’.

The wavelet transform results in simplified versions of the image along with all of the information necessary to reconstruct the original (i.e. to rebuild the complete wave or image). At this point, all of the information can be kept and encoded as a lossless compressed image. Alternatively, the final image can be based on a simplified version, with only the most significant detail added back into the wave. The result of this quantisation process is a much smaller file, but one that has thrown away some of the less important image information (i.e. lossy compression).

The wavelet compression has several key advantages over other lossy compressions. Wavelet compression is capable of both lossy and lossless compression. Lossy wavelet compression is more discriminating - it can preserve the important detail of the file while simplifying and smoothing over less significant features. It can also operate over a much larger area of the image at once (often the whole image), avoiding the introduction of unwanted ‘artefacts’.

The working through of the wavelet transform also produces a ‘by-product’ that offers interesting display potential. The increasingly simplified waves can be encoded in several different ways so that as the file is decompressed it can grow in size (i.e. spatial resolution) or become increasingly more detailed (i.e. fidelity). Importantly, wavelet compression can also be lossless compression, stopping short of discarding information but still optimising the data’s structure.

A fuller explanation, using JPEG 2000 as an example, can be found in JISC Digital Media’s document What is Wavelet Compression?

Open vs. proprietary

Efficient compression and good functionality are real assets in digital file formats, especially when editing or delivering. But these technologies are often proprietary: controlled by patents, related to commercial imaging products or controlled by copyright.

The digital media community has become more wary of proprietary standards after a succession of formats have been released and failed commercially. Manufacturer support has been withdrawn, making access to media complicated, even impossible.

Although it might seem sensible, then, to always and only use open standards which are not tied to a single manufacturer or group of manufacturers, it is not always that simple. Certain features may only be available within proprietary formats, and open formats may include features in their specification that are not actually supported by any of the applications available to create or access them.

It is very important to keep in mind this distinction between specification and application. Features and functionality described in file format specifications may not be possible to achieve in the real world, due to a lack of support by the software used to encode them or decode them.

This issue of support is often a problem with open standard formats upon initially release. Open standard usually take a long time to develop, with input from many interested parties. When they are eventually released (or even before official release) you can expect to see a number of different applications based on the standard, each favouring a slightly different set of features. With open standards, it is rare for all of the features to receive full community support.

As you might expect, there are generally few, initial support issues with a proprietary file format, since it has been created for a specific application. However, since it is tied to the fortunes of a commercial company, the format as a whole is vulnerable to being changed or dropped without notice or regard for its users.

The distinction between open and proprietary standards is not always clear-cut. Proprietary formats which become de facto or industry standards occasionally become open standards (e.g. Kodak’s FlashPix format). Sometimes, too, a company will adapt an open format into one of its own - particularly if it can be used to rival the proprietary formats of its competitors. In this case an open format will develop into a proprietary product.

In selecting particular formats for use within your digital imaging project, you will need to consider both the openness of the file format (and sometime the individual features within that format), and the way the format is supported by applications.

Additional functionality

In addition to the way they compress data, different file formats have different unique features or functionality. Of special interest to digitisation projects are the abilities of file formats to store additional information alongside the main media data. This may include embedded metadata, closed captions even several different versions of the media ranging from uncompressed (an archival ‘master’ copy) to highly compressed (perhaps for delivery on mobile devices) grouped together.

Digital still image formats

Raster vs. Vector

Digital still images fall into two main categories: raster (or ‘bit-mapped’) images and vector (‘object-oriented’) images. Raster images take the form of a grid or matrix, with each picture element (pixel) having a unique location and independent colour value. Vector files are really just a set of mathematical instructions that are used by a drawing program to construct an image. There is a third category of formats known as metafiles, which are able to contain both raster and vector images.

Raster images

A basic understanding of the raster image is essential, since it is the most common category of image created and used within digitisation projects. All scanners and digital cameras produce raster images and most output devices (print and screen) also use them. TIFFs, JPEG/JFIFs, and GIFs are common examples of raster file formats.

Raster images take the form of a grid or matrix. This pattern becomes easily visible as the image is magnified (i.e. viewed at more than 100% - see box below). Each square (pixel) within the matrix occupies a unique position and can be edited separately.

Figure 1: The raster grid. Photo: Standard test image from the University of Waterloo. No copyright restrictions

The image above has been magnified by 800% and 1600% to reveal its grid structure. Each square of colour is a pixel.

Raster images are internally very simple. If you examine their coding, you will typically find some brief header information describing the structure of the file followed by a series of values, each describing the colour of the individual pixels.

Since a raster image records information for each pixel, its file size can be quite large. For an uncompressed raster image, the file size will be directly related to its pixel dimensions (spatial resolution) and the extent of the colour information recorded for each pixel (its colour resolution or ‘bit-depth’). A more detailed explanation of spatial and colour resolution can be found in JISC Digital Media advice document: The Digital Still Image.

Although most raster file formats are similar in structure, they can be distinguished by the amount of information they record per pixel (i.e. their bit-depth), the methods used to record their code more efficiently (their compression), and the additional functionality they offer (e.g. transparency layers, colour management or metadata support). They can also be divided into open formats and proprietary formats (see above).

Vector images

While most raster images result from a digital capture process, vector images are typically created and displayed within drawing programs. Common vector images include 2- and 3-D architectural drawings, flow charts, logos and fonts. They consist of lines, curves and shapes with editable attributes such as colour or fill. Because they are defined by mathematical equations, they are more easily transformed than raster images. Unlike raster images, vectors are ‘resolution independent’: they can be reshaped or rescaled without losing quality.

Vector images are looked at in greater depth in JISC Digital Media’s advice document Introduction to the Vector Image Format.

Encapsulating formats (Metafiles and PDLs)

There is a third category of file formats that can contain or encapsulate raster and vector images. This category includes metafiles and Page Description Languages (PDLs). In addition to holding different types of images and text within the same file, these formats enable, to varying degrees, their contents to be consistently displayed and used across different computer programs and operating systems.
Metafiles contain lists of commands that will draw or display an image when they are run. Vector drawing commands are most common, but metafiles can also include raster information or text. Sometimes they are little more than a kind of envelope, containing an instruction to open up another image file.

Common metafile formats include the Computer Graphics Metafile (CGM), Windows Metafile (WMF), and Enhanced Metafile (EMF). The Computer Graphics Metafile is older and will run on most computer operating systems. The other two were developed specifically for the Windows operating system, but are used more widely.

Page Description Languages (PDLs) are computer languages used to describe information about layout, fonts and graphics to a printer or display device. The classic Page Description Language is PostScript (PS), which was designed to provide detailed instructions to computer printers. PostScript can contain raster or vector images, but was not developed as a graphic file format in the way that metafiles were. However, later incarnations of PostScript, such as EPS and PDF, have been developed very much with the exchange of graphics in mind, blurring the distinction between PDLs and metafiles.

EPS (Encapsulated PostScript) is a file format based on PostScript. Specifically intended to encapsulate graphics, it uses a subset of PostScript commands, allows only one image per file, and ignores page sizes or positioning. EPS became something of an industry standard for sending images to commercial printers because it was able to ‘lock’ the images and layout so that they could not be altered. It was intended to be completely cross-platform, although proved more reliable on the Macintosh platform than the PC. EPS has now been largely superseded by the PDF.

Like EPS, PDF (Portable Document Format) is based on PostScript, but it adds, rather than subtracts, functionality. PDF can include text and image, multiple-pages, hotspots, links, extensive metadata and, like EPS, be locked to stop editing. It also supports a range of compressions, both lossy (JPEG) and lossless (ZIP). The PDF has now become a de facto standard for exchanging documents on the Web, is almost universally supported within the print industry, and is increasingly being used simply as a container for exchanging images.

PostScript, EPS and PDF were all developed by Adobe, but are created and used within many other applications and have become industry standards. There are other common proprietary formats with similar functionality, but their use tends to be limited to their own applications. Examples include the Quark file, which is used for page layout, and Photoshop’s PSD, which is primarily a raster image format but also able to accommodate vector information, such as type, within its layers.

As the example of Photoshop’s PSD format indicates, the distinction between raster and vector images is less clear-cut. Many of the newer formats now act as metafiles or encapsulating formats - capable of holding raster and vector information in different layers. This trend can also be seen in the emerging JPEG 2000 (primarily a raster format) and in the Flash, SWF, and SVG formats (primarily vector).

Advantages of encapsulating formats

These formats do some or all of the following:

• Enable the exchange of files across different platforms and applications
• Include raster, vector, text and layout information on different layers within the same file
• Provide added functionality, including hotspots and linking
• Allow easier resource discovery by using internal metadata and unique digital object identifiers
• Support multi-page images

Enable ‘locking’ to provide security and assist in rights management

Digital video formats

Over the past few years the relatively small number of available video file formats has grown exponentially. An immense number of file formats are now in common use for preservation, re-mastering or for access. Different file formats are suited to different purposes. For instance, the open source-over-proprietary argument may not extend to delivery, if the aim is to reach as many users as possible. File size and required bandwidth (i.e. data rate) are limiting factors when selecting a file format for delivery but perhaps not so much when selecting a format for long-term preservation, where a very large file size may be acceptable.

For instance, at the current time the H.264 format (MPEG-4) is growing in significance as a delivery format, while archives begin to take advantage of the uncompressed possibilities of JPEG2000.

Different formats employ different ‘tricks’ in order to reduce file size and bandwidth and (hopefully) reduce the deterioration of the image. Interframe and intraframe compression are mentioned above, but another common tactic is chroma sub-sampling. Chroma sub-sampling relies on the fact that human vision is more sensitive to contrast than colour. In effect a higher resolution monochrome image in overlaid with a lower resolution coloured image. In chroma sub-sampling the saving in file size is made at the expense of some colour information.

Whether or not these sacrifices in visual precision are acceptable depends very much on the purpose the video will serve. What is acceptable for the oral history project may not be acceptable for the film archive. But just what do the differences between different video file formats actually look like?

Presented below is the same video clip in several popular file formats for comparison purposes. The clip is available for download only, as several of these versions are too large to be streamed over the Internet (and so would be unsuited to web delivery). The clip is purely computer generated, this rules out the variables of in-camera recording format and lens quality as a purely virtual animation sequence involves no camera and no lens. The correct codec will need to be installed on your machine in order to play back the video files - conduct a web search for the named codec or use an open source player such as VLC player. In addition, your desktop computer may not have sufficient capability to playback uncompressed video in real time due to its high data rate.

The ‘quality’ of images which are moving can be difficult to judge so still image examples of each codec are also included for comparison purposes.

Sample 1: Uncompressed, 10bit, 4:4:4 subsampling
Download Video (Right-click and save as…) (177MB)

Standard: Standard definition PAL
Duration: 4.2 seconds
Frame size horizontal: 720 pixels
Frame size vertical: 576 pixels
Frame rate: 25 frames per second
Frame type: progressive
Wrapper file format: .avi
Format/codec: r210 (uncompressed)
Bit depth per channel: 10bit
Chroma sub sampling: 4:4:4
Data rate: 354 Mbps
File size: 177 MB

Sample 2: Uncompressed, 10bit, 4:2:2 subsampling
Download Video (Right-click and save as…) (110MB)

Standard: Standard definition PAL
Duration: 4.2 seconds
Frame size horizontal: 720 pixels
Frame size vertical: 576 pixels
Frame rate: 25 frames per second
Frame type: progressive
Wrapper file format: .avi
Format/codec: HDYC (uncompressed)
Bit depth per channel: 10 bit
Chroma sub sampling: 4:2:2
Data rate: 221 Mbps
File size: 110 MB

Sample 3: Uncompressed, 8bit, 4:2:2 subsampling
Download Video (Right-click and save as…) (85MB)

Standard: Standard definition PAL
Duration: 4.2 seconds
Frame size horizontal: 720 pixels
Frame size vertical: 576 pixels
Frame rate: 25 frames per second
Frame type: progressive
Wrapper file format: .avi
Format/codec: UYVY
Bit depth per channel: 8 bit
Chroma sub sampling: 4:2:2
Data rate: 166 Mbps
File size: 85 MB

Sample 4: DV
Download Video (Right-click and save as…) (15MB)

Standard: Standard definition PAL
Duration: 4.2 seconds
Frame size horizontal: 720 pixels
Frame size vertical: 576 pixels
Frame rate: 25 frames per second
Frame type: progressive
Wrapper file format: .avi
Format/codec: dvsd
Bit depth per channel: 8 bit
Chroma sub sampling: 4:2:0
Data rate: 30 Mbps
File size: 15 MB

Sample 5: MPEG-4, Profile/level: Main@L3.1*
Download Video (Right-click and save as…) (4.6MB)

Standard: Standard definition PAL
Duration: 4.2 seconds
Frame size horizontal: 720 pixels
Frame size vertical: 576 pixels
Frame rate: 25 frames per second
Frame type: progressive
Wrapper file format: .mp4
Format/codec: AVC1
Bit depth per channel: 8 bit
Chroma sub sampling: 4:2:0
Data rate: 9 Mbps
File size: 4.6 MB

Sample 6: MPEG-2, Profile/level: Main@Main*
Download Video (Right-click and save as…) (3MB)

Standard: Standard definition PAL
Duration: 4.2 seconds
Frame size horizontal: 720 pixels
Frame size vertical: 576 pixels
Frame rate: 25 frames per second
Frame type: progressive
Wrapper file format: .mpg
Format/codec: MPEG2
Bit depth per channel: 8 bit
Chroma sub sampling: 4:2:0
Data rate: 9 Mbps
File size: 3 MB

*MPEG (Moving Picture Expert Group) formats often involve a whole host of variable parameters. Sets of these parameters become popular for different applications. For instance, MPEG-4 is used for both Internet delivery and Blu-ray movie discs. The latter application offers far more visual information per frame. These sets of parameters are defined as ‘profiles’ and ‘levels’.

Digital audio formats

Until recently digital audio formats were limited to a small standardised number, fit for purpose for the professional broadcast and production industries. Originally, the properties of consumer digital audio were defined by the capabilities of the digital video technology of the time, which led to the popular use of PCM (Pulse Code Modulation) digital audio. With the recent rise of delivery methods, newer audio formats have been adapted to suit the changing trends and capabilities of audio playback and storage systems.

With PCM the raw encoding of an analogue audio signal into digital information is done by sampling the signal at regular discrete intervals. This can be done either at the recording stage (analogue to digital conversion) or when repurposing a digital file. Samples are rounded to the nearest discrete number of evenly spaced levels (quantised). The amplitude values are at a constant ratio to the amplitude, and this linear recording is often referred to as LPCM (linear PCM). This raw data (called a bitstream) is contained in a wrapper, a structured container which helps the appropriate software or digital system interpret and use the new file. Numerous wrapper formats (including video formats) can contain mono, stereo, standard surround or multi-channel audio files of varying sizes.

Below are some examples of some uncompressed recordings which are contained in WAV format. Note the relative bit rates and size of each file, listed in the corresponding table. Each recording was captured separately so as not to introduce any re-sampling and no further analogue or digital processing has been done. The recordings were taken with a simple setup of Earthworks QTC-1 microphones straight into a USB interface with no further digital or analogue processing to the signal. The piece being played is an excerpt from the first movement of Beethoven’s piano sonata no. 14 (Op 27).

Beethoven’s Moonlight Sonata by JISC Digital Media. All files © University of Bristol, 2009

Aside from linear PCM encoding, other techniques exist to deliver audio across a narrow bandwidth or at a faster speed. Logarithmic PCM is a technique where amplitude values are spaced close together at low amplitudes and far apart at high amplitudes. This approach works well for speech and requires less bits per sample than linear PCM. A-law and μ-law compression are both logarithmic transformations used in telephony, and can be applied in digital audio systems. These forms of compression reduce samples to 8-bits whilst retaining the dynamic range equivilant to 14-bit linearly quantised samples.

There are further alternate coding architectures to PCM, more than will be mentioned here, but we will briefly look at a few important ones. Whereas linear PCM encoding reads discrete individual values, differential encoding uses techniques to predict the relative difference between samples. As the value of the difference between one sample to the next is less than the absolute amplitude values recorded in PCM, less bits are needed to record the information. There are two prominent implementations of this practice that are worth mentioning here, Adaptive Differential Pulse Code Modulation (ADPCM) and Delta-Sigma encoding.

The ADPCM encoder makes use of the fact that adjacent audio samples are on the whole similar to one another. It computes the difference between the current input sample and the predicted value of the next sample using components of the decoder to compute the predicted value. ADPCM is commonly used in digital audio files including .aif and .wav and in some VOIP (Voice Over Internet Protocol) applications. In theory the performance of ADPCM can just as good results as linear PCM in terms of fidelity at lower bit rates. Other dedicated codecs for compressing speech exist such as CELP, used for GSM mobile telephony.

DSD (Direct Stream Digital) is a relatively new audio format which uses an extreme form of differential encoding. Sigma delta encoding runs at very high sample rates (between 2.8MHz - 5.6MHz) and similar to ADPCM records the difference between amplitude values but does this at a 1-bit resolution. This means that each new amplitude value is measured to be either higher or lower than the previous value and the output is either 1 for louder or 0 for quieter (i.e. 1-bit). These minute recordings of variation in amplitude can recreate waveforms due to the size of the sample rates being used. Using these high sample rates also means that quantisation noise is spread over a very wide range of frequencies at a much reduced intensity. This technique is capable of reproducing frequencies from 0Hz (D.C) to 100KHz with a dynamic range of 120db.

Whilst uncompressed audio files may not be nearly as large as uncompressed video files of the same duration, they can still prove problematic for web delivery. An uncompressed stereo 44.1KHz, 24-Bit WAV file contains just over 1MB of information for every 4 seconds of audio. The same file has a bit rate of 2,116.8 kbits/s which is considerably large for efficient online delivery. Compressing audio files lowers this bit rate so they can be downloaded (either via a direct download, streamed, or played via a browser)

A popular lossy technique, the MPEG 1 compression algorithm, uses psychoacoustic modelling algorithms that analyse the frequency spectrum of an audio signal, and then remove data intelligently at and around frequency bands with relatively little or no content. Although fidelity is more improved than other compression techniques, the effects of this become more audibly pronounced when harshly applied, and signals can sound ‘pixalated’ as anomalies are introduced. This is a high compression technique aimed at producing high fidelity results, and elements of this have been expanded upon to create new codecs, such as the open source MPC (Musepack) and the LAME codec, due to the propietray restrictions of the MP3 codec. Lossless compression, as discussed in the section above on compression, is used for decreasing the size of audio files without losing any audio fidelity. Monkey’s Audio and FLAC are two codecs that utilise this technique. An example of the FLAC format is given in the embedded player below.

One of the problems when presenting these formats and types of compression is that in a practical sense there is no one-size fits all solution when considering which method to use. Format and compression choice should be based on the objectives of a project. A spoken word podcast of a lecture recording can have its fidelity compromised considerably to improve accessibility via web downloading, whereas the online streaming of a performance may require greater fidelity to give clarity to music. Audio fidelity is a subjective concept, and perhaps the best way to understand the effects of audio data compression is to listen to varying amounts of compression. Although there is a wealth of codecs available for delivering compressed audio files, the audible distinction between them can sometimes be difficult to perceive. As a result a selection of files, of the same format (MP3), is presented below to highlight audible effects of differing bit rates, a primary concern when delivering compressed audio files.

All of the tracks in the player below are surrogates from an uncompressed PCM 48KHz 24-bit master WAV file, 33.9MB in size. Note that the FLAC file retains the sampling rate and bit depth but is only 18.5MB in comparison.

Compressed Examples by JISC Digital Media. All files © University of Bristol, 2009

Last updated: 03 December 2009
Published in: Digitising analogue media | Managing your digital resources | Finding and using digital media
Tags: compression | digital collections | file formats

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Digitisation Services

Last updated: 03 November 2009
Published in: Managing a project | Digitising analogue media
Tags: analogue collections | digital preservation | digitisation | outsourcing

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Summary

JISC Digital Media contacted a number of digitisation service providers for more information about the services they supply. The following list is not an endorsement of any of the services, but is provided to help you identify services to evaluate in more detail.

If you are a member of the JISC Digital Media mailing list, you may find other members have direct experience with these or other service providers.

You may also find it useful to read JISC Digital Media's To Outsource or to Digitise In-house?

Service providers are listed alphabetically and organised by the media they specialise in:

• Still image digitisation
  
• Moving image digitisation
• Audio digitisation

Still image digitisation

Most of the services listed here will offer standard scanning and/or photography, so we have highlighted the more specialised services they provide.

BOPCRIS Digitisation Service www.soton.ac.uk/library/bopcris/
We asked the service provider to use up to 100 words to summarise and promote their service, and to indicate how they can satisfy the needs of those within HE/FE and the cultural heritage sector: BOPCRIS Digitisation Service based at the Hartley Library, University of Southampton specialises in the production of digital page images from bound books. Specialist book scanners and a conservation environment enables fragile pages to be captured in their bindings. Images are captured in full colour or grey scale at variety of resolutions and a number of output formats are offered. Printed texts can be converted to machine readable formats with markup. Supporting bibliographic data can be extracted and exported as MODS with associated metadata including METS, MIX and PREMIS.
Specialist services offered (beyond standard scanning/ photography)		Bulk slide scanning
		Microfilm or fiche scanning
		Scanning/photography of fragile books
		Photography of museum objects
		Photography of fine art works
		On-site service available
		Other services: Digital images only produced.
Size of largest flat item that can be captured at 300dpi without interpolation		700mm × 500mm
Information supplied		December 2007

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Capita Total Document Solutions www.capita-tds.co.uk
We asked the service provider to use up to 100 words to summarise and promote their service, and to indicate how they can satisfy the needs of those within HE/FE and the cultural heritage sector: Capita Total Document Solutions has thirty years' experience in providing imaging services to the archive, preservation, education and library community via both microfilm and digital technologies. We have extensive knowledge and experience in handling fragile and historic material. Our specialist, state of the art equipment and quality assured processes enable us to work with a variety of delicate and fragile maps, books and other documents found in archives and museums. We offer fast and accurate microfilm and microfiche conversion and imaging, which conform to Mellon guidelines for archival permanence. With regard to digital solutions we have the latest flatbed book scanners, digital scanners and microfilm digitisers to ensure the production of high quality images.
Specialist services offered (beyond standard scanning/ photography)		Bulk slide scanning
		Microfilm or fiche scanning
		Scanning/photography of fragile books
		Photography of museum objects
		Photography of fine art works
		On-site service available
		Other services: Electronic Document Management Software; Full text OCR (Optical Character Recognition); Full OCR / ICR (Intelligent Character Recognition) / Semi Structured forms processing; Intelligent Data Recognition services; Invoice processing; Document storage and retrieval (physical); Document destruction services (Green/Secure); Scan on demand; ASP hosted solutions; Web hosting of documents and retrieval; Microfilm filming, processing and duplication; Electronic post room; Indexing services; 16mm and 35mm film processing; Large format scanning; Preservation services; Digital preservation services; Card index conversion; Archive services; Printers and Scanning equipment; Maintenance of hardware; Scanning Consumables e.g. toners
Size of largest flat item that can be captured at 300dpi without interpolation		A0 (841mm × 1189mm)
Information supplied		January 2008

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Digital Capture Solutions www.bcu.ac.uk/dcs/
We asked the service provider to use up to 100 words to summarise and promote their service, and to indicate how they can satisfy the needs of those within HE/FE and the cultural heritage sector: Digital Capture Solutions (DCS) developed from the digital library for Birmingham City University. We expanded into the market place in 2001 after a surge in demand to use our digitisation services. DCS can help in preserving heritage by offering a specialised service, producing the highest quality digital versions possible of original (analogue) formats. Our unique large format Zeutschel overhead scanners for bound and unbound material can scan to the highest resolution available (400dpi at A0). Clients include libraries, archives and record offices, art galleries and museums, learned societies, and private companies. We handle all original material to current NPO standards and are centrally located in Birmingham.
Specialist services offered (beyond standard scanning/ photography)		Bulk slide scanning
		Microfilm or fiche scanning
		Scanning/photography of fragile books
		Photography of museum objects
		Photography of fine art works
		On-site service available
		Other services: Large Format scanning bound and unbound originals; Digital Preservation Services, Ability to scan originals up to 400dpi true optical resolution. Specialised large format scanners for fragile bound and unbound original materials.
Size of largest flat item that can be captured at 300dpi without interpolation		A0 (841mm × 1189mm) - 400dpi (true optical i.e. without interpolation)
Information supplied		March 2008

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FSB (FenPast Scanning Bureau) www.cambridgeshire.gov.uk/leisure/archives/FSB/
We asked the service provider to use up to 100 words to summarise and promote their service, and to indicate how they can satisfy the needs of those within HE/FE and the cultural heritage sector: The FSB are part of Cambridgeshire Archives and Local Studies Service based in Cambridge. We have been specialising in the digital imaging of historical documents, glass slides, negatives, museum objects and archaeological finds for seven years. Our small team offer a friendly, personal service for small digitisation projects. Any items we accept for scanning are stored in Cambridgeshire Archives' own strongrooms. Cambridgeshire Archives is accredited by the National Archives as a repository for holding public records
Specialist services offered (beyond standard scanning/ photography)		Bulk slide scanning
		Microfilm or fiche scanning
		Scanning/photography of fragile books
		Photography of museum objects
		Photography of fine art works
		On-site service available
		Other services: We accept jobs for 1-5000 items or batches up to 5000 items. We can create master TIFF, preview and thumbnail jpeg images for the web. Also, undertake poster and leaflet design.
Size of largest flat item that can be captured at 300dpi without interpolation		A0 (841mm × 1189mm). Plus up to 2 metres × 3 metres by seamless digital stitching of images using Photoshop
Information supplied		January 2008

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Heron www.heron.ingenta.com
We asked the service provider to use up to 100 words to summarise and promote their service, and to indicate how they can satisfy the needs of those within HE/FE and the cultural heritage sector: Heron has been providing cost-effective digitisation and copyright clearance services to the HE and FE communities for almost ten years. Heron also provides software services for those who do their own scanning.
Specialist services offered (beyond standard scanning/ photography)		Bulk slide scanning
		Microfilm or fiche scanning
		Scanning/photography of fragile books
		Photography of museum objects
		Photography of fine art works
		On-site service available
		Other services: Proof-read text conversion from scanned images or photocopies output to PDF (or other formats for VIP use)
Size of largest flat item that can be captured at 300dpi without interpolation		A3 (297mm × 420mm)
Information supplied		September 2007

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IImage Retrieval (UK) Ltd www.imageretrieval.co.uk/
We asked the service provider to use up to 100 words to summarise and promote their service, and to indicate how they can satisfy the needs of those within HE/FE and the cultural heritage sector: IImage Retrieval has all the expertise, skill and professionalism required for all your company’s document management needs. Our in-house bureau specialises in the preservation scanning of books, maps, x-rays, negatives, photos and paper scanning using Kofax Accent and VRS producing high quality images. We have also invested heavily in microfilm digitising equipment making us one of the largest digitisation bureaus in the UK with 10 microfilm scanners. IIRI have developed their own web based document management viewer, available as a managed web server, supplied as a boxed or bespoke product.
Specialist services offered (beyond standard scanning/ photography)		Bulk slide scanning
		Microfilm or fiche scanning
		Scanning/photography of fragile books
		Photography of museum objects
		Photography of fine art works
		On-site service available
		Other services: I2S large format book scanning equipment - IImage Retrieval is the sole distrubutor for the UK, Ireland & US.We are also resellers for Contex Scanners, Easy Software and secured biometrix memory sticks and hard drives.
Size of largest flat item that can be captured at 300dpi without interpolation		Maximum 50" wide @ 600 dpi (drum scanner) or A1 Book scanner.
Information supplied		September 2008

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IDP Digitisation Services idp.bl.uk/pages/services.a4d
We asked the service provider to use up to 100 words to summarise and promote their service, and to indicate how they can satisfy the needs of those within HE/FE and the cultural heritage sector: With over a decade spent managing large and small digitisation, web and image management projects in the heritage sector, IDP has unrivalled expertise and experience. Our team of ten practising professionals frequently give advice to individuals and institutions worldwide and have worked as consultants, digitisers, image management and website designers on several external projects. We have trained staff in UK and worldwide, worked on-site and off-site and consistently produced excellent quality images to schedule and within budget. You will not find a service with more experience or specialised expertise in the heritage sector.
Specialist services offered (beyond standard scanning/ photography)		Bulk slide scanning
		Microfilm or fiche scanning
		Scanning/photography of fragile books
		Photography of museum objects
		Photography of fine art works
		On-site service available
		Other services: Consultancy, post-production services, database/image management design and implementation, web page design and implementation, training
Size of largest flat item that can be captured at 300dpi without interpolation		225MB at 16-bit
Information supplied		September 2007

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Max Communications Ltd www.maxcommunications.co.uk
We asked the service provider to use up to 100 words to summarise and promote their service, and to indicate how they can satisfy the needs of those within HE/FE and the cultural heritage sector: Max Communications Ltd has established itself as the leading provider of digital image solutions to the educational and cultural sectors. We specialise in high quality digitisation services and place an overriding emphasis on developing long-term relationships with clients, based on our product quality and friendly professional service. We are uniquely placed to assist with digitisation projects due to the experience gained from working with other leading institutions faced with the same challenges and opportunities. Along with free no obligation sample tests, we offer highly competitive pricing and no quibble guarantees.
Specialist services offered (beyond standard scanning/ photography)		Bulk slide scanning
		Microfilm or fiche scanning
		Scanning/photography of fragile books
		Photography of museum objects
		Photography of fine art works
		On-site service available
		Other services: A full range of image manipulation services, raw digital camera file conversion and comprehensive photographic printing services
Size of largest flat item that can be captured at 300dpi without interpolation		2 metres × 3 metres in one capture. Plus an unlimited size, by seamless digital joining of images
Information supplied		September 2007

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MicroFormat UK Ltd www.microformat.co.uk
We asked the service provider to use up to 100 words to summarise and promote their service, and to indicate how they can satisfy the needs of those within HE/FE and the cultural heritage sector: MicroFormat is one of the UK's largest and oldest document conversion specialists, with over thirty-five years' experience of supplying archive preservation, document management and indexing services. Our bureau is based in Rochester, Kent, providing quality service to UK and international customers We offer a complete document scanning, microfilming and indexing service. We also offer microfilm scanning and microfiche scanning for those who require digital imaging from existing records. Our core expertise is in document handling, and we have been of service to HE/FE and the cultural heritage sector for many years. MicroFormat is part of the MicroFormat Group bv, Netherlands.
Specialist services offered (beyond standard scanning/ photography)		Bulk slide scanning
		Microfilm or fiche scanning
		Scanning/photography of fragile books
		Photography of museum objects
		Photography of fine art works
		On-site service available
		Other services: Microfilming, indexing, image processing
Size of largest flat item that can be captured at 300dpi without interpolation		A0
Information supplied		January 2009

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Perspectives www.perspectivesnet.com
We asked the service provider to use up to 100 words to summarise and promote their service, and to indicate how they can satisfy the needs of those within HE/FE and the cultural heritage sector: As one of the principal Scottish providers of archive digitisation, we have considerable experience of scanning and handling sensitive archive material. We have worked on large on and off site digitisation projects and have provided ongoing digitisation of collections in museums and archives. We can assist with both public and private image collections throughout the UK.
Specialist services offered (beyond standard scanning/ photography)		Bulk slide scanning
		Microfilm or fiche scanning
		Scanning/photography of fragile books
		Photography of museum objects
		Photography of fine art works
		On-site service available
		Other services: A wide variety of original formats digitised to high resolution including glass plate negatives, lantern slides, medium and large format negative and transparencies and 35mm material. Document and artwork scanning and photography. File captioning, adding metadata, conversion to jpeg, pdf, etc. Archive management and web delivery.
Size of largest flat item that can be captured at 300dpi without interpolation		A1
Information supplied		August 2009

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Relic Imaging www.relicimaging.com
We asked the service provider to use up to 100 words to summarise and promote their service, and to indicate how they can satisfy the needs of those within HE/FE and the cultural heritage sector: Relic Imaging offers high-end digital archival photography to museums, galleries and other organisations in the cultural heritage sector. We specialise in high quality production whether you have 10 or 10, 000 objects. We can digitise your collection including 3d objects, framed artwork, jewellery, prints & drawings, glass plates, manuscripts, textiles or illustrations from delicate and rare volumes. A professional and friendly approach, along with careful handling and consideration for delicate items, provides our clients with a quality service time and again.
Specialist services offered (beyond standard scanning/ photography)		Bulk slide scanning
		Microfilm or fiche scanning
		Scanning/photography of fragile books
		Photography of museum objects
		Photography of fine art works
		On-site service available
		Other services: 360 degree panoramas of galleries/interiors. QuickTime object movies.
Size of largest flat item that can be captured at 300dpi without interpolation		1 metre × 1.5 metres in one capture, or multiples thereof by stitching files.
Information supplied		June 2008

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Scriptura www.sciptura.co.uk
We asked the service provider to use up to 100 words to summarise and promote their service, and to indicate how they can satisfy the needs of those within HE/FE and the cultural heritage sector: Scriptura provides a comprehensive range of high quality digitisation services to meet the needs of research libraries, archives, museums and other cultural heritage organisations. Particular emphasis is placed on the safe handling and protection of fragile originals. Scriptura employs appropriate methods and equipment to produce archive quality digital photographic masters. Scriptura was founded following seven years of work on major academic research projects that, in collaboration with conservators and custodians, pioneered an approach to the digitisation of early manuscripts from special collections housed within the University of Oxford, Trinity College Dublin, the Royal Irish Academy, and the National Library of Ireland.
Specialist services offered (beyond standard scanning/ photography)		Bulk slide scanning
		Microfilm or fiche scanning
		Scanning/photography of fragile books
		Photography of museum objects
		Photography of fine art works
		On-site service available
		Other services: Photography of maps, prints, architectural drawings, etc. Design and development of image delivery systems for the web and desktop.
Size of largest flat item that can be captured at 300dpi without interpolation		35.53 inches × 26.67 inches (image stitching can be utilised for larger originals)
Information supplied		September 2007

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Sinclair Scott Scanning Solutions Ltd www.sinclair-scott.com
We asked the service provider to use up to 100 words to summarise and promote their service, and to indicate how they can satisfy the needs of those within HE/FE and the cultural heritage sector: We have been involved in 'high-end' image reproduction for many years and supply specialsit services in digital imaging solutions from our modern premises in East Kilbride, South Lanarkshire to the archival, academic, commercial and scientific sectors. Unlike most archiving and document scanning services, our organisation has its roots in the pre-press and printing sectors. Consequently, our high-resolution scanners (Heidelberg S3900 Drum Scanner and Linotype-Hell Topaz Flatbed Scanner) are acknowledged to be among the finest in the industry, specifically designed to deliver outstanding definition and image quality. Together with our skills and experience, we are able to meet the most exacting standards in reproduction, and create precise facsimilies of source material.
Specialist services offered (beyond standard scanning/ photography)		Bulk slide scanning
		Microfilm or fiche scanning
		Scanning/photography of fragile books
		Photography of museum objects
		Photography of fine art works
		On-site service available
		Other services: We specialise in high resolution drum and flatbed scanning and handle a wide range of originals including photographs, glass plates, transparencies, prints, manuscripts, journals, rare books, fine arts, textiles, herbarium, coins and medals.
Size of largest flat item that can be captured at 300dpi without interpolation		520mm × 620mm (Flexible)
Information supplied		October 2008

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TownsWeb Archiving Ltd www.townswebarchiving.com
We asked the service provider to use up to 100 words to summarise and promote their service, and to indicate how they can satisfy the needs of those within HE/FE and the cultural heritage sector: Our flat-bed systems are unique. Our office based equipment can digitise items up to 1.5 × A0 in one single pass and our portable systems can digitise items up to A1 size. We are very experienced in dealing with old, large and fragile items as well as smaller items such as books, film and slides. Our expertise extends to software and web development, creating public search engines and allowing payments to be taken online. Please take a look at www.townswebarchiving.com where you will see that we have worked with museums, art galleries, records offices and private companies - including Royal Doulton, Purdeys, Thomas Cook and RNIB.
Specialist services offered (beyond standard scanning/ photography)		Bulk slide scanning
		Microfilm or fiche scanning
		Scanning/photography of fragile books
		Photography of museum objects
		Photography of fine art works
		On-site service available
		Other services: Graphic design services to repair and restore digital images; Bespoke software development services to create new archive systems; Web development services to create public access to archives; Payment gateway services to allow the public to pay for their access
Size of largest flat item that can be captured at 300dpi without interpolation		1.5 × A0 (841mm × 1189mm)
Information supplied		October 2007

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UK Archiving www.ukarchiving.co.uk
We asked the service provider to use up to 100 words to summarise and promote their service, and to indicate how they can satisfy the needs of those within HE/FE and the cultural heritage sector: Our aim is to excel in the delivery of preservation and archiving services through the use and development of microfilming, scanning and digitisation techniques.
Specialist services offered (beyond standard scanning/ photography)		Bulk slide scanning
		Microfilm or fiche scanning
		Scanning/photography of fragile books
		Photography of museum objects
		Photography of fine art works
		On-site service available
		Other services: Preservation microfilming; COM (Computer Output to Microfilm) creation; OCR (Optical Character Recognition)
Size of largest flat item that can be captured at 300dpi without interpolation		A1 (594mm × 841mm)
Information supplied		September 2007

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University of London Computer Centre (ULCC) www.ulcc.ac.uk/digitisation.html
We asked the service provider to use up to 100 words to summarise and promote their service, and to indicate how they can satisfy the needs of those within HE/FE and the cultural heritage sector: We specialise in the digitisation of small/high value collections that demand customisation and state-of-the-art output. Our service encompasses scanning, photography and the transfer of analogue audio/video to post-digitisation imaging and optimisation. We uphold strict handling, storage and security practices (BS5454:2000), and are experienced with digitising fragile materials. One of our strengths is the capacity to operate as a one-stop-shop that caters for the whole life cycle of an object, from guidance and digitisation, through to data management, storage, access and long-term preservation. We can provide a complete service to ensure that the potential of your digital assets is realised.
Specialist services offered (beyond standard scanning/ photography)		Bulk slide scanning
		Microfilm or fiche scanning
		Scanning/photography of fragile books
		Photography of museum objects
		Photography of fine art works
		On-site service available
		Other services: We offer digitisation of static (including historic photographic processes) and time-based media (transfer of analogue mechanical and magnetic audio and video to archival digital formats), and also other services, such as post-digitisation imaging and optimisation, transcoding for streaming and podcasts, customised metadata extraction and indexing, digital respository/bespoke image management solutions, consultancy and training.
Size of largest flat item that can be captured at 300dpi without interpolation		A0 (concealed stitching can be used for larger items)
Information supplied		October 2008

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Moving image digitisation

Creative Video Associates Ltd www.cva.co.uk/archive.htm
We asked the service provider to use up to 100 words to summarise and promote their service, and to indicate how they can satisfy the needs of those within HE/FE and the cultural heritage sector: We can clean and evaluate Umatic, Beta SP, Digital Betacam, Beta SX, HDCAM, HDCAM-SR, IMX, DVCAM, DVCPRO and DV tapes as well. We offer an archive clean service which is beneficial to the long term storage of videotape and is often used to derive the optimum signal from the tapes before transfer or digitisation.
Specialist services offered		Digitisation of analogue video formats (see list below)
		Capture/transcoding of digital videotape formats (see list below)
		Conservation of physical videocassettes
		Audiovisual collection care advice
		Generation of technical audiovisual metadata
		Provision of digital video/metadata management systems
		Digitisation project management
		Digital video hosting/online delivery
		Digital video restoration
Other services offered
Date information gathered		November 2009

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Daydream Asset Services www.daydream.co.uk/ser_related_asset_mgnt.asp
We asked the service provider to use up to 100 words to summarise and promote their service, and to indicate how they can satisfy the needs of those within HE/FE and the cultural heritage sector: Established since 1995, Daydream are a leading provider of digital asset management systems and related digital asset services, including: media digitisation, video capture & transcoding, metadata generation & management and online digital media streaming. Our DAM platform, FocusOPEN, provides many of these services as built-in features, but we can also cater for individual digitisation and encoding projects with our flexible, cost-competitive media asset services. We have worked with organisations in both the private and public sectors, including English Heritage and the London Business School.
Specialist services offered		Digitisation of analogue video formats (see list below)
		Capture/transcoding of digital videotape formats (see list below)
		Conservation of physical videocassettes
		Audiovisual collection care advice
		Generation of technical audiovisual metadata
		Provision of digital video/metadata management systems
		Digitisation project management
		Digital video hosting/online delivery
		Digital video restoration
Analogue videotape formats handled		Digitisation of 1" videotape
		Digitisation of 2" (Quad) videotape
		Digitisation of 1/2" (e.g. EIAJ) videotape
		Digitisation of U-matic videocassettes
		Digitisation of Phillips VCR videocassettes
		Digitisation of MII videocassettes
		Digitisation of Laserdiscs
		Digitisation of Video-8 videocassettes
		Digitisation of Hi8 videocassettes
		Digitisation of VHS videocassettes
		Digitisation of S-VHS videocassettes
		Digitisation of BetaMax videotape
		Digitisation of Betacam videocassettes
		Digitisation of Betacam SP videocassettes
Digital videotape formats handled		Capture/transcoding of Digital-8
		Capture/transcoding of DigiBeta
		Capture/transcoding of D1
		Capture/transcoding of D2
		Capture/transcoding of D3/D5
		Capture/transcoding of Ampex DTC
		Capture/transcoding of D9
		Capture/transcoding of DV/Mini-DV
		Capture/transcoding of DVCAM
		Capture/transcoding of DVPRO
		Capture/transcoding of Digital-VHS
		Capture/transcoding of Micro-MV
Digital delivery formats		DVD-video
		DVD(data)
		Blu-ray video (Profile 2 compliant)
		Blu-ray data (BD-r)
		Portable USB or Firewire hard drive
		SATA-2 hard drive
		LTO data tape
		DLT data tape
		Digibeta
		HDCAM-SR
		DV/MiniDV
		DVPRO50
		DVPRO100(DVPROHD)
		FTP
Other services offered		Editorial & Library Management Controlled Vocabulary & Taxonomy Design Data Migration Scanning & image digitisation Document management OCR. Delivery via SFTP also possible.
Date information gathered		March 2009

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Digital Visual www.digitalvisual.net
We asked the service provider to use up to 100 words to summarise and promote their service, and to indicate how they can satisfy the needs of those within HE/FE and the cultural heritage sector: All video goes through a NLE meaning it can be digitally enhanced, edges cleaned, cropped to any size and colours restored. We can also split into individual files and re-titled.
Specialist services offered		Digitisation of analogue video formats (see list below)
		Capture/transcoding of digital videotape formats (see list below)
		Conservation of physical videocassettes
		Audiovisual collection care advice
		Generation of technical audiovisual metadata
		Provision of digital video/metadata management systems
		Digitisation project management
		Digital video hosting/online delivery
		Digital video restoration
Analogue videotape formats handled		Digitisation of 1" videotape
		Digitisation of 2" (Quad) videotape
		Digitisation of 1/2" (e.g. EIAJ) videotape
		Digitisation of U-matic videocassettes
		Digitisation of Phillips VCR videocassettes
		Digitisation of MII videocassettes
		Digitisation of Laserdiscs
		Digitisation of Video-8 videocassettes
		Digitisation of Hi8 videocassettes
		Digitisation of VHS videocassettes
		Digitisation of S-VHS videocassettes
		Digitisation of BetaMax videotape
		Digitisation of Betacam videocassettes
		Digitisation of Betacam SP videocassettes
Digital videotape formats handled		Capture/transcoding of Digital-8
		Capture/transcoding of DigiBeta
		Capture/transcoding of D1
		Capture/transcoding of D2
		Capture/transcoding of D3/D5
		Capture/transcoding of Ampex DTC
		Capture/transcoding of D9
		Capture/transcoding of DV/Mini-DV
		Capture/transcoding of DVCAM
		Capture/transcoding of DVPRO
		Capture/transcoding of Digital-VHS
		Capture/transcoding of Micro-MV
Digital delivery formats		DVD-video
		DVD(data)
		Blu-ray video (Profile 2 compliant)
		Blu-ray data (BD-r)
		Portable USB or Firewire hard drive
		SATA-2 hard drive
		LTO data tape
		DLT data tape
		Digibeta
		HDCAM-SR
		DV/MiniDV
		DVPRO50
		DVPRO100(DVPROHD)
		FTP
Other services offered		Digital Cropping Noise reduction Titles/ re-edit Custom flash players/ Web design Video streaming server. Delivery in Flash Video Quicktime Real Video or Mpeg formats.
Date information gathered		March 2009

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Greatbear Analogue and Digital Media www.thegreatbear.net/audio-video-transfer/
We asked the service provider to use up to 100 words to summarise and promote their service, and to indicate how they can satisfy the needs of those within HE/FE and the cultural heritage sector: We can transfer a wide range of old analogue formats to digital using some of the best of yesterday's and today's technology. All transfer machines are carefully chosen and maintained to offer the best quality at reasonable prices. The Focusrite analogue to digital conversion hardware we use is excellent sounding and offers a range of sample rates up to 24-Bit / 96 Khz for the highest quality transfers.
Specialist services offered		Digitisation of analogue video formats (see list below)
		Capture/transcoding of digital videotape formats (see list below)
		Conservation of physical videocassettes
		Audiovisual collection care advice
		Generation of technical audiovisual metadata
		Provision of digital video/metadata management systems
		Digitisation project management
		Digital video hosting/online delivery
		Digital video restoration
Analogue videotape formats handled		Digitisation of 1" videotape
		Digitisation of