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OSU Library Metadata: A Guideline to Best Practices: Format

This site provides guidelines for OSU's local implementation of CDP Dublin Core Metadata Best Practices Version 2.1.1


Label: Format
Maps to Dublin Core Element Name: Format
Maps to MARC field (in World Cat): 500, 300 (extent), 340 (medium)
Mandatory: Yes, if applicable
Repeatable: Yes

Refinement Name Refinement Label Definition
Extent Extent The size or duration of the resource
Medium Medium The material or physical carrier of the resource







Scheme Name Scheme Label Definition
IMT IMT Internet Media Type


Dublin Core Definition: Format

Dublin Core Definition: The physical or digital manifestation of the resource.

Dublin Core Comment: Typically, Format may include the media type or the dimensions of the resource. Format may be used to describe the software, hardware, or other equipment needed to display or operate the resource. Examples of dimensions include size and duration. Recommended best practice is to select a value from a controlled vocabulary (for example, the list of Internet Media Types [MIME] defining computer media formats).

Comment/Context: Format

The OSU Library will use the Format element to record digital manifestation of the resource and use the Internet Media Type (IMT scheme). 

Use the Extent refinement to record a resource’s file size and/or duration. 

Use the Medium refinement to describe an item’s physical (as opposed to its digital) nature. 

The Format element is reserved for describing the access file only (be it image, audio, or video). Technical metadata relating to the digitization process (i.e., scanner model, scanner resolution, color schemes, file size of the master file, etc.) should be recorded in the Technical Specifications element.

Input Guidelines: Format

  1. Some digital objects may involve more than one format, for example, an oral history interview may have audio formats and text format transcriptions. Use separate Format elements for the refinements Extent and Medium.
  2. Enter formats for different purposes as separate Format elements, i.e., separate file size and
    duration entries.
  3. Select electronic format terms from the Internet Media Types (IMT) standardized list, formerly
    known as MIME types.
  4. Record the file size as kilobytes (Kb), megabytes (Mb), etc. Not bytes.
  5. For audio and video file formats include the duration (i.e., play time) of the resource.
    New media types and applications are always emerging. If the resource format being described is
    not yet part of the IMT type list, follow the IMT convention by selecting a broad category of object
    format (audio, video, application, etc.) for the first part of the IMT type, then use as a brief
    identifier for the second half of the IMT type the file name suffix that is usually attached to files of
    this format. See "audio/WAV" example below.


Examples: Format


Format [Extent]



file size for a 3 megabyte file

1 minute

play time for a digital audio file

4 x 5 in. Physical dimensions of original photograph (digitized as a JPEG image file)
00:59:00 Oral history audio time duration


Format [Medium] Comment
color lithograph

Physical medium of original postcard

black and white photograph Physical medium of original photograph
color photograph Physical medium of original photograph






Format [IMT]                                



visual file in JPEG format


visual file in TIFF format


text file in HTML format


File in PDF format.


video file in MPEG format


sound file in MP3 format


sound file in WAV format (See Input Guideline 6 of section 4.10 for explanation of new media types)

image/jp2 visual file in JP2000 format

visual file in GIF format