WebCodecs VideoFrame Metadata Registry

Editor’s Draft,

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This registry is intended to enumerate the metadata fields that can be attached to VideoFrame objects via the VideoFrameMetadata dictionary.

Status of this document

This section describes the status of this document at the time of its publication. A list of current W3C publications and the latest revision of this technical report can be found in the W3C technical reports index at https://www.w3.org/TR/.

Feedback and comments on this specification are welcome. GitHub Issues are preferred for discussion on this specification. Alternatively, you can send comments to the Media Working Group’s mailing-list, public-media-wg@w3.org (archives). This draft highlights some of the pending issues that are still to be discussed in the working group. No decision has been taken on the outcome of these issues including whether they are valid.

This document was published by the Media Working Group as an Editor’s Draft. This document is intended to become a W3C Recommendation.

Publication as an Editor’s Draft does not imply endorsement by W3C and its Members.

This document was produced by a group operating under the W3C Patent Policy. W3C maintains a public list of any patent disclosures made in connection with the deliverables of the group; that page also includes instructions for disclosing a patent. An individual who has actual knowledge of a patent which the individual believes contains Essential Claim(s) must disclose the information in accordance with section 6 of the W3C Patent Policy.

This document is governed by the 03 November 2023 W3C Process Document.

1. Registration Entry Requirements

A registration entry is a document describing one or several metadata entries, and has the following requirements:

  1. Each metadata entry is defined as a separate VideoFrameMetadata dictionary member.

  2. Each metadata entry must be serializable.

  3. Each metadata entry must be defined by a W3C specification that has reached consensus in the originating Working Group.

  4. The specification defining each metadata entry must provide clearly defined semantics. In particular, interactions with the media processing pipeline (encoders, decoders, renderers, etc.) should be well defined.

  5. A candidate registration entry must be announced by filing an issue in the WebCodecs GitHub issue tracker so they can be discussed and evaluated for compliance before being added to the registry. If the Media Working Group reaches consensus to accept the candidate, a pull request should be drafted (either by editors or by the party requesting the candidate registration) to register the candidate. The registry editors will review and merge the pull request.

  6. Existing entries may be changed after being published, through the same process as candidate entries. Possible changes include modification of the link to the public specification.

  7. Existing entries may be deprecated. This requires Media Working Group consensus, and if still active, consensus of the Working Group that originated the registration entry specification.

2. VideoFrameMetadata members

member name public specification
segments Human face segmentation

3. Privacy Considerations

Please refer to the section Privacy Considerations in [WEBCODECS].

4. Security Considerations

Please refer to the section Security Considerations in [WEBCODECS].


Terms defined by reference


Normative References

Paul Adenot; Bernard Aboba; Eugene Zemtsov. WebCodecs. URL: https://w3c.github.io/webcodecs/