The registration is not intended to include any information on whether a
codec format is encumbered by intellectual property claims. Implementers and
authors are advised to seek appropriate legal counsel in this matter if they
intend to implement or use a specific codec format. Implementers of
WebCodecs are not required to support the AVC / H.264 codec.
This registration is non-normative.
Status of this document
This section describes the status of this document at the time of its publication. Other documents may supersede this document. 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.
Publication as a Working Draft does not imply endorsement by the W3C Membership.
This is a draft document and may be updated, replaced or obsoleted by other documents at any time.
It is inappropriate to cite this document as other than work in progress.
This document was produced by a group operating under the W3C Patent Policy.
The group does not expect this document to become a W3C Recommendation. 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.
The codec string must begin with the prefix "avc1.", and contain a suffix of 6
characters as described in Section 3.4 of [rfc6381].
NOTE: The common "avc3." prefix is intentionally not included. This prefix does
not signal a material difference to decoder inputs, so it is omitted for
simplification. For the purposes of this registration, authors should simply
map "avc3." to "avc1.".
2. VideoDecoderConfig description
A VideoDecoderConfig.description may or may not be required by the
AVC codec depending on the bitstream format of the AVC content to be decoded.
If the VideoDecoderConfig.description includes an AVCDecoderConfigurationRecord, as defined by [iso14496-15], section
5.3.3.1, it will be assumed that the bitstream is in "avc" format.
NOTE: This format is commonly used in .MP4 files, where the player generally
has random access to the media data.
NOTE: "annexb" format is described in greater detail by [ITU-T-REC-H.264],
Annex B. This format is commonly used in live-streaming applications, where
including the SPS and PPS data periodically allows users to easily start
from the middle of the stream.
The AvcBitstreamFormat determines the location of AVC Sequence Parameter
Set (SPS) and Picture Parameter Set (PPS) data, and mechanisms for packaging
the bitstream.
SPS and PPS are described in greater detail in sections G.3.41 and G.3.55 of [ITU-T-REC-H.264].
annexb
SPS and PPS data are included periodically throughout the bitstream.
NOTE: This format is described in greater detail by [ITU-T-REC-H.264],
Annex B. This format is commonly used in live-streaming applications,
where including the SPS and PPS data periodically allows users to easily
start from the middle of the stream.
NOTE: This format is described in greater detail by [iso14496-15],
section 5.3.3.1. This format is commonly used in .MP4 files, where the
player generally has random access to the media data.