Digitization Guidelines

Scanning Specifications

Any materials digitized for the NIUDL must adhere to the following minimum requirements. Any divergences from these minimum requirements will be documented in the project's specifications.

Text (Books, Newspapers, Documents)

Image Types Bit Depth Color Space Resolution (ppi) Scale File Format
B&W Text Only 1-bit Bitonal 600dpi 100% (1:1) TIFF (uncompressed or lossless compression)
B&W Text with Illustrations 8-bit Grayscale 400dpi 100% (1:1) TIFF (uncompressed)
Text with Continuous-Tone Images & Photos (Color) 24-bit RGB 400dpi 100% (1:1) TIFF (uncompressed)

Photographs (Prints)

Image Types Bit Depth Color Space Resolution (ppi) Scale File Format
B&W Photographs 8-bit Grayscale 600dpi 100% (1:1) TIFF (uncompressed)
Color Photographs 24-bit RGB 600dpi 100% (1:1) TIFF (uncompressed)

Photographs (Negatives and Slides)

Image Types Bit Depth Color Space Resolution (ppi) Scale File Format
B&W Negatives and Slides 8-bit Grayscale 5,000 pixels across the longest side 100% (1:1) TIFF (uncompressed)
Color Negatives and Slides 24-bit RGB 5,000 pixels across the longest side 100% (1:1) TIFF (uncompressed)

Large Format (Posters and Maps)

Image Types Bit Depth Color Space Resolution (ppi) Scale File Format
B&W Posters and Maps 8-bit Grayscale 5,000 - 10,000 pixels across the longest side 100% (1:1) TIFF (uncompressed)
Color Posters and Maps 24-bit RGB 5,000 - 10,000 pixels across the longest side 100% (1:1) TIFF (uncompressed)

Video Recordings

Video Types Codec Resolution Sampling Size Data Rate Frame Rate File Format
Archival Preservation Uncompressed YCbCr or lossless JPEG2000 640 x 480 (4:3) or 1280 x 720 (16:9) 30 bit 30 MiB/s 30p (24p for film) AVI, QuickTime, or MXF
Access Preservation DV or ProRes 640 x 480 (4:3) or 1280 x 720 (16:9) 30 bit 30 MiB/s 30p (24p for film) AVI or QuickTime
Born Digital DV or ProRes >1280 x 720 (16:9) 30 bit >50 MiB/s 30p (24p for film) AVI or QuickTime

Scanning Practices and Procedures

Guidelines for Digital Images

  • If digitizing a multi-part resource, always digitize the entire item, including the binding or wrapper and any blank pages.
  • Ensure that there is adequate space around each side of the resource (approximately 1/8"), including the gutter of any opposing pages. Each edge should be clearly defined.
  • If the image contains important color information, scan with a ruler and color checker, providing space between the resource and the ruler.
  • Always use a plain underlay, preferably dark gray, that will contrast with the resource being digitized.


  • Materials are handled as little as possible and stored in a secured location when not in use.
  • Bound materials are scanned lying flat, but should not be opened beyond the point where the binding is stressed.
  • Scanning of tightly-bound materials occasionally requires removing the binding, which is done in consultation with the Project Manager and Content Provider.
  • Glass is used to flatten pages for scanning, but only when it poses no danger to the materials. Fingers or pens should never be used to flatten resources.
  • Uncut book edges will be cut by scanning technicians, unless otherwise requested.
  • Materials are handled with clean bare hands, unless otherwise requested.

Scanner Calibration

  • Scanners are calibrated every week using targets to enure accurate color capture and focus.
  • Monitors are calibrated annually.
  • Scanners are serviced every year.

Image Manipulation

Image manipulation is kept to a minimum after scanning and should always be avoided whenever possible. In the event that significant problems are identified, the batch will be re-scanned. For this reason, consistent quality control is extremely important. Some exceptions to image manipulation include:

  • Images may be desewed or rotated, as needed.
  • Images are often cropped, leaving a small border of space (1/8") around each item.

Filenaming and Storage

Files are given meaningful names, typically indicating the collection or project that the files belong to using an alpha-numberic identifier. The name should always end with numerals in a sequnce of at least three digits, seperated from the identifier using the underscore character (_). Filenames should not contain any spaces or other special characters.

If the collection contains resources with multiple parts (e.g. books or manuscripts), each part should be assigned a unique and meaningful identifier after the collection identifier, preceded by an underscore (_). For example:


--> SEADL999_CambodianManuscripts025_001.tif

--> SEADL999_CambodianManuscripts025_002.tif

--> SEADL999_CambodianManuscripts025_003.tif

Files are stored on the University Libraries' Network Attached Storage (NAS) in the Scanning directory during production, then copied to the Staging directory when they are ready to be published. Files are removed from the Scanning directory after they have been published and reviewed for quality.


Two mechanisms are used for publishing digital content to NIUDL: batch ingest and form ingest. Batch ingest involves creating a Submission Information Package (SIP), which typically consist of a MODS record and an archival file in the appropriate directory structure, which varies by content type. This allows NIUDL to publish many assets at the same time. Form ingest involves publishing one file at a time through the NIUDL front-end and does not require technical knowledge or server access, allowing those outside of NIUDL staff to participate in publishing, include staff from other Library units and partners at other libraries. Ingest forms are developed by the Digital Collections and Metadata Librarian in consultation with the Project Manager.