Digitization Standards

This information is intended to specify Discovery, Technology and Publishing's current standards for local digitization of materials for online digital library collections. While digitization standards used during outsourced projects may differ from these, the images presented online will be consistent in resolution, bit depth and file type throughout all collections.

Faculty projects are handled on a case-by-case basis, and imaging standards vary according to their needs and the intended use of the materials. Digitization standards for interlibrary loan, document delivery and electronic reserves are noted separately below.

Standards for Digital Collections

Image Specifications for Initial Capture

Type of Original

Bit Depth

Resolution

Compression

File Format

Books (text, figures, illustrations) 24-bit (color) 600 ppi Uncompressed TIFF
Slides (35mm) 24-bit (color) 600 ppi at 900% (5400 ppi)
Uncompressed TIFF
Oversized Items (maps, posters, large books) 24-bit (color) 600 ppi Uncompressed TIFF
Project Specific (may vary based on needs and intended use) 4-, 8- or 24-bit (black and white, grayscale or color) as appropriate 600 ppi Uncompressed TIFF

Image Specifications for Online Delivery

Type of Original Bit Depth Resolution File Format
Books (text, figures, illustrations) 24-bit (color) 72 ppi Lossless JPEG2000 *
Slides (35mm) 24-bit (color) 72 ppi Lossless JPEG2000 *
Oversized Items (maps, posters, large books) 24-bit (color) 72 ppi Lossless JPEG2000 *
Project Specific (may vary based on needs and intended use) 4-, 8- or 24-bit (black and white, grayscale or color) as appropriate 72 ppi Lossless JPEG2000 *
* Note: JPEG2000 is a wavelet compressed image that is not widely supported in browsers. While images are stored on servers in this format, they are dynamically converted to JPEG images before appearing in browser windows.

Text Standards

Purpose Description Format Standard
Structured Transcription of Text Literal text transcription encoded in XML. All new text collections are encoded in this manner. Specialized software is required to index, manage and deliver these texts.
XML Files conform to the Text Enconding Initiative's P5 release, or a modified TEI-based schema available here
Page Images PDF page images PDF Not currently supported.

 

Standards for Interlibrary Loan, Document Delivery and Electronic Reserves

Image Specifications for Delivery of ILL and Electronic Reserve Materials

Type of Original Bit Depth Resolution File Format
Book chapter, article, illustration, etc. 4-, 8- or 24-bit (black and white, grayscale or color) as appropriate 300 ppi PDF