National Library of Australia


DIGITISATION SUBGROUP OF THE CMF IT WORKING GROUP

 

The Department of Communications, Information Technology and the Arts has established a number of working groups reporting to its Corporate Management Forum. The Information Technology Working Group, in late 1999, established a subgroup devoted to digitisation of collection materials by national collecting institutions in its portfolio and other related cultural organisations in the Australian Capital Territory.

The Digitisation Subgroup met during 1999 and 2000 on a near-monthly basis and was chaired by Dr Katy Gillette, Manager of Information Technology at the National Museum of Australia. The group held its last formal meeting on 6 December 2000; it will now meet on an informal basis every 4 months. The participating institutions are:

Australian Institute of Aboriginal and Torres Strait Islander Studies

Australian War Memorial

National Archives of Australia

National Gallery of Australia

National Library of Australia

National Museum of Australia

National Portrait Gallery

ScreenSound Australia.

 

Terms Of Reference

In recognition of whole-of-government initiatives and policies to move government services and business online, the Digitisation Subgroup was formed with the following terms of reference:

  1. To exchange information on digitisation activities and initiatives within the participating institutions.
  2. To examine strategies and best practice in digitisation management across the institutions.
  3. To explore possibilities for developing or adopting common standards and specifications for digitisation, especially with a view to promoting inter-operability.
  4. To explore opportunities for shared business arrangements, including the potential for common service providers or provision of services between institutions.
  5. To explore possibilities for cooperative public access initiatives.
  6. To explore mechanisms to avoid duplication of effort.
  7. To report monthly to the Corporate Management Forum IT Working Group.

 

Objectives

The objectives of the group were to:

 

Principles of Digitisation

The following principles for digitisation programs were developed by the Digitisation Subgroup of the Corporate Management Forum’s IT Working Group.

Digitisation of cultural heritage materials is a complex and costly endeavour. Many issues need to be addressed by any institution embarking on digitisation programs, but the Digitisation Subgroup has identified a number of fundamental principles that can guide decisions about what and/or how to digitise. It agreed that the first two are fundamental principles, while the remaining ten are a menu from which to select depending on the goals of the program (Principle 1).

  1. Goal directed

Deciding how and what to digitise will vary according to the goals of the project. Decisions about quality and quantity will be bounded by goals, priorities and available resources. For institutions that anticipate using a set of images only on the Web, then digitising at a lower resolution (quality) may be an option (but consider Principle 3). When archival (high-resolution) digital images are wanted, then perhaps fewer items (quantity) in a particular collection can be digitised and selection must be guided by clear goals, eg collection management, preservation, access and other goals. For audio and video material, bit and sampling rates correspond to resolution and the above principles apply. Ultimately, setting goals includes a cost-benefit decision-making process.

  1. Driven by institutional policy

Digitisation programs should reflect the strategic and operational goals of the institution and obey policies. For example, at some institutions there is a policy that collection materials do not leave the premises to be photographed, digitised, or copied by any other means. When such policy is to be knowingly violated, risk minimisation procedures should be instituted. At a higher level, digitisation programs should reflect internal policies regarding collection access, preservation, collection management and marketing. Note that in turn digitisation policy should be driven by principles such as these.

  1. Long term thinking

Digitisation of collection materials can be a complex and expensive process. Thinking about future uses and needs for the digital copies we create today may help to avoid duplication of effort, using formats of limited longevity and applicability, cheap short-term solutions that are not cost-effective long-term.

  1. Technological and procedural re-evaluation

The technology of digitisation, like all areas of technology, is continually changing. Regular re-evaluation of technological approaches and processes will play a role in optimising the efficiency and effectiveness of digitisation programs.

  1. Risk minimisation

Many potential risks attend digitisation programs, from loss or damage of originals to using technological solutions that do not meet required standards. Approaching digitisation of collection materials as a series of smaller, controllable subprojects can have many advantages in minimising risks, as can good quality control procedures.

  1. Integrate digitisation into institutional activities

At the outset of the digitisation program it is desirable that digitisation should be seen as part of a larger, routine process rather than as an isolated, separate activity. That larger process can include:

  1. Eliminate duplication

The routine processes adopted for managing digital collections and records should preclude, or at least minimise, any double handling or unnecessary duplication of products. For example, digitising 50 images for Web presentation at a low screen resolution or, for audio, at a low sampling rate, and later re-digitising at high resolution or high sampling rate for other purposes is a waste of time and resources, and could be hard on collection materials where originals are being scanned or played again on a tape recorder.

  1. Provenance of foreign goods

Collecting institutions have many reasons for borrowing materials from each other, eg for exhibition purposes. In some of these cases both parties may agree that the borrower make digital copies of these items for a variety of purposes (eg condition reporting, online exhibition). It is vital that information management systems for digital materials can adequately record the provenance of these digital ‘borrowings’ to avoid confusion about the custodianship.

  1. No breach of copyright or moral rights

Digitisation of cultural materials and provision of access to digital copies should comply with intellectual property legislation, with moral rights, and with cultural protocols with respect to Indigenous and other cultural groups. In turn, it is good practice to ensure that users also comply with legal and cultural conventions.

  1. Collaboration

In recognition of whole-of-government initiatives and policies to move government services and business online, collecting institutions are increasingly collaborating to provide access to quality information about Australia’s cultural heritage. Collaboration with other institutions and commercial partners can contribute to minimising duplication of effort, improving access to digital collections, achieving efficiencies, improving knowledge about and processes for digitisation.

  1. Part of a broader information strategy

Digital copies are information – manage them! is another way to summarise this principle. Digital copies should be part of a broader strategy to manage collections and access to those collections, to apply good information management practices to managing digital copies (eg file naming, creating database records including ‘standard’ metadata, cross referencing, secure storage of physical and online digital formats, recording of any manipulations), and indeed to managing any intermediate reproductions, such as photographs. Planning for the maintenance and preservation of digital information should be part of the strategy.

  1. Originals are indispensable

Digital copies are excellent access ‘surrogates’, but not substitutes for the original item, which must also continue to be managed according to best practice.

  1. Faithful reproduction

Digital copies should faithfully reproduce the material provided for digitisation, including all faults and artefacts of the original in the first instance. Manipulation can be performed on a subsequent version to enhance the reproduction, if requested, for presentation purposes and so on. All such manipulations must be documented.

 

Developing minimum specifications for digitisation

The Subgroup spent the majority of its time working towards the goal of developing agreed minimum specifications for digitisation. Its most original work was in the development of the foregoing underlying principles that underpin decisions about specifications.

There was a concerted effort to develop a specifications matrix for static visual materials with one axis denoting the format of the ‘original’ material was displayed (eg 4x5 colour transparency, map, original manuscript, print publication) and the other denoting the nature of the specification ( eg resolution, file formats, file naming, metadata). In the end the group re-combined all the formats of originals into one category – static visual materials. It then specified minimum specifications for some parameters but recommended institutional discretion for other parameters (see below). In other words, it was shown to be difficult to set common minimum specifications across the board, and to find terminology that was unanimously agreed.

It had been intended to develop a similar matrix model for digitisation of audio and audio-visual originals, but the checklist of parameters developed for visual materials applies equally well for these other formats, with some changes of terminology.

While the work on specifications was intended to be one of the major tasks for the Subgroup, it does not seem that this activity can be taken any further. The major output has been the principles of digitisation referred to above. However, a valuable checklist of specifications has resulted and will be a useful tool.

 

Specifications for static visual materials

In deciding the following specifications the group worked on the assumption that:

Specification Area

Suggested Minimum Specifications and Practices

Master copy

 

Delivery medium, carrier

Any delivery medium that can be played/read, dependent upon how the organisation will use it

Tonal, pixel depth (input)

12 bits per pixel for all except microfilm and printed text where 8-bit greyscale may suffice

Tonal, pixel depth (output)

8 bits per pixel for all except microfilm and printed text where bitonal may suffice

File formats

TIFF latest version, PC bit order

Compression type & level

Uncompressed, or lossless if compression is needed

Resolution (spatial dimension in pixels)

Not below 300dpi with reference to original item, with the proviso that the scanning resolution must capture the smallest detail; spatial resolution as recommended by the California Digital Library is suitable for standard transparency and negative sizes

Manipulation, enhancements, cropping

None outside what is inherent in the digitisation process

Calibration of equipment (gamma setting, tonal range, dynamic range, colour standards) for capture

Colour standards should meet ICCC; other settings should meet appropriate international standards for PC environment

Cross-platform requirements

Specify that content can be read by PC and Macintosh

Metadata (header, caption)

Specify as per institutional needs

File naming

Each file must have a unique identifier including institution name, in a format that can be used by the institution

Measurement of capture system performance/Quality Control

Specify as per institutional needs the quality level expected of supplier (eg maximum error rate)

Handling of special formats, eg concatenation/

Specify as per institutional needs, recognizing that it is always preferable to capture the whole work in one file

Orientation

As per original or as per institution’s specified needs; where it is not clear from the original it may be necessary to advise supplier where ‘top’ is, whether original is landscape or portrait, etc

Polarity (pos., neg.)

Specify as per institution’s needs, usually same as original

Light levels

Specify that image capture must be carried out without exposing original to excessive light and that original should be immediately re packaged after capture

File sizes, eg for digital photos

Specify file sizes where this is necessary (particularly where other resolution definitions make no sense eg for 3D objects). A specification here may impact on other specifications (eg it may not be possible to achieve the resolution level specified within a specified file size).

Documentation, batch reports, lists eg of file names, file sizes, CD nos.

Specify as per institution’s needs

Handling/Care of original

Specify according to preservation needs/best practice guidelines

Labelling of carrier and packaging

Specify as per institution’s needs, noting that care should be taken in labeling not to damage integrity of the carrier

Text conversion, encoding requirements

Normally this would be a derivative - care should be taken not to lose master file; specify accuracy level, depending on need, the document type (eg ASCII, XML, plain text)

   

Derivatives

Many of the above areas need also be specified for derivatives

 

Contacting the group

The contact for the Digitisation Subgroup is Lydia Preiss, Manager of Collection Preservation at the National Library of Australia, lpreiss@nla.gov.au .


Last modified: August 09 2004.