Final Report on the Academic Image Exchange Appendix E.

Developed at a meeting of the AIC held at Yale University on 4 August 2000.

E1. Standards the AIC will apply in creating and managing master digital image files and associated metadata

Image formats

Principle: master files will supply the same resolution of a 35mm slide or better

File format: Uncompressed TIFF

Color depth, etc.:

• Color images: 24bit color, 8 bits per channel, no alpha or other types of channels.

• Greyscale (where appropriate) - 8-bit greyscale

• Bitonal (only likely to be included in the collection in exceptional circumstances)

Resolution: 3072 x 2048 pixels at 72 dpi (resolution may be higher where images are based on formats larger than 35mm slides)

File size: Likely to be between 14-25MB depending on format of source image

Post-processing: AIC will post-process (crop, color correct, filter, sharpen) raw TIFFs according to guidelines to be developed

The AIC metadata record

Principle: to develop of a VRA 3.0 conformant implementation that is consistent with the requirements of the AIC's online service, the AIC's business interests, and the AIC's data and rights management requirements

The AIC metadata record will be developed for the AIC by early 2001 on the basis of existing VRA version 3.0.

File-naming conventions

Principle: To adopt conventions that supports the AIC's data management and dissemination needs with minimum redundancy

Two strategies will be reviewed, revised and one selected for implementation by end September 2000.

Strategy one (based on U Michigan's file-naming convention). Image files maintain the names supplied by their creators and are entered into directories which are themselves named by some combination of (a) a standardized abbreviated contributor name (b) a time/date stamp (c) a CD number - i.e. as will be necessary where contributors supply several CDs on a given date. Post processed image files will retain their original names and be stored in sub-directories of those just described.

Strategy two. Image files are supplied with some normalized AIC-generated name that may be mapped onto the file-naming convention described above

E2. Standards the AIC will require of image contributors

Principle: By supplying guidelines to its contributors, the AIC will help to ensure the quality and consistency of its collections and services. Where contributors supply images in digital form, the guidelines will also assist the AIC in preserving those digital images on their contributors' behalf

Formats AIC will require/prefer from contributors

Non-digital image formats: Where non-digital formats are concerned, the AIC will consider digitizing (or assisting in the digitization of) images that are supplied in formats to be agreed between the AIC and its contributors. AIC may prefer 35 mm slides but will accept both larger formats and materials that are film positive,s film negatives, and prints, pending discussion and review of sample materials.

Digital formats may be supplied as TIFFs or as Kodak PhotoCD. They will typically be supplied on CD-ROMs (to be returned by AIC to the contributor) created in conformance with ISO 9660. The image should conform to the standards specified above with the following exceptions:

• File formats: TIFFs may be LZW compressed
• Resolution: AIC may accept resolutions that have a minimum true optical resolution of 1024x768 pixels.
• Post processing: AIC prefers raw scans. Post-processed images may be accepted after review by AIC staff.

Image documentation supplied by contributors

Principal: Image must be supplied with a minimum level of administrative and descriptive metadata. Descriptive metadata will be sufficient to enable an appropriately skilled individual to create a full AIC metadata record for the underlying image.

Minimum level metadata will consist of

• global attributes (e.g. attributes that may be supplied once and associated with all images in a contributed n image set)
  • contributor name
  • contributor contact information (email, phone, fax, postal address)
  • date contributed to AIC

• Item-level attributes (attributes that must be supplied for each image)
  • filename/slidenumber/image identifier
  • title or description of work
  • creator or cultural context and date of work
  • photographer
  • date photographed if available
  • museum/location of work

Rights information may be a global attribute (e.g. where the same rights information applies to all images contributed in an image set) or an item-level attribute (e.g. where rights information differs across images included within an image set). Where rights information is a global attribute, it may be supplied by AIC staff at accession

Contributors are encouraged to supply any additional metadata that exist such as

• additional descriptive metadata (e.g. item notes, description of work, etc)
• additional technical information (e.g. hardware profile, film type, scanner hardware, scanning notes, etc. that may exist for contributed digital images)

Metadata must be logically associated with images (whether supplied in digital or non-digital form) e.g. through application of some internally consistent file-naming convention

Metadata must be supplied in machine readable form as delimited ASCII files which are sufficiently documented so that they:

• Identify tables and fields
• Map tables/fields to the minimum metadata requirement as specified above
• Supply abbreviation keys or codebooks where appropriate
• Supply information about use of controlled vocabularies

AIC will undertake to assist potential contributors by developing web-accessible guidelines for contributors including examples of acceptable and unacceptable practices, pointers to related information resources, etc.

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