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Media metadata properties

Problem statement / use cases

  • users want access to metadata stored within various media formats
  • often immanent metadata properties are better way to store metadata for authors and users so that these properties do not become separated from the file

Proposed solutions

DOM interface to access metadata properties

A DOM interface to access metadata properties the on HTMLImageELement, HTMLObjectElement, and HTMLMediaElement. Attributes might be included such as:

interface HTMLImageElement : HTMLElement {
  readonly attribute DOMString mediaCopyright; // returns the IPTC standard copyright notice
  readonly attribute DOMString mediaTitle; // returns the IPTC standard title
  readonly attribute DOMString mediaKeywords; // returns the IPTC standard keywords
  readonly attribute DOMString digitalPhotograph; // returns a boolean indicating from other
             // metadata whether a resource is from a digital camera
  readonly attribute DOMString mediaEvent; // returns the IPTC standard event
  readonly attribute DOMString mediaHeadline; // returns the IPTC standard headline
  readonly attribute DOMString mediaCaption; // returns the IPTC standard caption

 DOMString metadataProperty(in DOMString protocol, in DOMString name ); // returns the DOMString
           // of the metadata property from the protocol by name
 boolean setMetadataProperty(in DOMString protocol, in DOMString name, in DOString value );
           // for use in editable DOMs with load/save capabilities

These DOM attributes could also be generalized to non IPTC metadata properties. For example for an IFRAME or OBJECT element embedding another HTML document the mediaTitle could return the title of the HTML document.

Other convenience accessors for IPTC properties could include:

  • people
  • category
  • supplemental-categories
  • byline
  • bylineTitle
  • credit
  • source
  • status

Liaison with IPTC to create new HTML/W3C metadata properties

Establish new metadata properties that accept HTML rather than only plain text. In addition to the plaintext IPTC caption property, it might also be useful to include HTML-rich properties for subject description (similar to caption) and visual description. Similarly adding metadata properties with a IRI data type or IRI list data type would provide richer metadata expression. For example:

  • role (space-separated list of role QNames)
  • transcript (an HTML valued property particularly for audible media)
  • subjectDescription (an HTML valued property for visual or aural media)
  • sensoryDescription (an HTML valued property for visual or aural media with greater subject detail and description of sensory aspects of the media)
  • describedby (URI space-separated list)
  • licenses (URI space-separated list)

Establish new interactive UA norms

Establish new interactive UA norms that expose image metadata properties in the UA inspector.

Discussion and evaluation


WG members should post feedback and other discussion to the WG’s list serve (the URI for the links below provides date information). Search on this email subject.

initial message (Robert Burns)

See also