Library of Congress

Digital Preservation

The Library of Congress > Digital Preservation > Feature Series > Meeting the Challenge > Federal Agencies Collaborate on Digitization Guidelines, Pt. II

Back to Meeting the Challenge

This is the second of three articles addressing the activities of the Federal Agencies Digitization Guidelines Initiative, this time with a focus on the Still Image Working Group. The next and last article in the series will focus on the Audio Visual Working Group.

Creating a digital collection with textual content, maps, photographic prints and negatives is a bit like piecing together a giant puzzle – and the technical requirements for the digital copies are one of the most important pieces. A host of decisions must be made before digitization (or scanning) gets under way. What are the standards for an acceptable digital copy in terms of color, resolution and faithfulness to the original? What metadata elements should be captured? A successful project depends on the right answers to these and many other questions.


The new Federal Agencies Digitization Guidelines Initiative aims to help agencies establish the right requirements for cultural heritage materials. The project has launched a Web site to document and share standards, best practices and other useful information.

Two specialized working groups are behind this effort: one for still images and another for audio-visual materials. Each group will produce guidelines covering the most crucial issues for digitizing historical, cultural and archival materials.

The Still Image Working Group has members from ten government agencies. Agencies currently involved include the U.S. Geological Survey, Library of Congress, National Agricultural Library, National Archives and Records Administration, National Gallery of Art, National Technical Information Service, National Library of Medicine, National Transportation Library, Smithsonian Institution, and the Government Printing Office.

In addition to agency representatives, the group has an advisory board of experts to provide a perspective from outside the government. The current board includes Stephen Abrams (California Digital Library), Rob Buckley (Xerox), and Don Williams (consultant).

The Still Image group will focus on developing guidelines for the activities associated with digital imaging and encoding, as well as handling metadata that will be embedded in digital files. A major goal is to implement standard measurements of image quality as set by project requirements. Another area of attention is the "reformatting" of printed, pictorial items, which will aim to develop categories and objectives to help frame questions about the intended use of the copies.

This is a highly collaborative effort, and input and feedback is actively encouraged from outside organizations as well as the public.

While much work remains, the group provides a number of resources through its Web site, including a large (and growing) glossary of technical terms, many of which are designated as specifically image related. Interested in definitions for such imaging terms as "color filter array," "downsampling," or "resolution"? Check them out in the group's glossary.

Other information available includes current institutional imaging guidelines and a list of formal industry standards. A toolkit of public domain software for image quality metrics and image file compliance will be available at a later date.

Michael Stelmach, manager of Digital Conversion Services at the Library of Congress and a key organizer of the group, is optimistic about its prospects. "So far, we’ve seen a very positive response to the collaboration," he said. "The issues we are tackling seem to resonate with others, both in the public and private sectors, who are working with digital conversion. Going forward, we hope that our work can serve as a useful reference for cultural heritage institutions."