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This specification defines the stream formats for use with the Encrypted Media Extensions [ENCRYPTED-MEDIA].
This registry is non-normative.
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 standards and drafts index.
This document was published by the Media Working Group as an Editor's Draft.
Publication as an Editor's Draft does not imply endorsement by W3C and its Members.
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 a work in progress.
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 that 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 18 August 2025 W3C Process Document.
This registry is intended to enhance interoperability among implementations and users of encrypted media streams with the Encrypted Media Extensions (EME) specification [ENCRYPTED-MEDIA]. In particular, this registry provides the means (1) to identify and avoid collisions among content type strings, and (2) to disclose information about encrypted data formats accepted by EME implementations to promote interoperability.
The registry maintains a mapping between content type strings and encryption format specifications, which describe the structure, semantics, and processing of the formats.
The strings are those used for the media type/subtype pairs in contentType values provided to Encrypted Media Extensions [ENCRYPTED-MEDIA] APIs.
This registry is not intended to include any information on whether a stream format is encumbered by intellectual property claims. Implementors and users are advised to seek appropriate legal counsel in this matter if they intend to implement or use a specific stream format.
| MIME type/subtype | Public Specification(s) |
|---|---|
|
audio/mp4
video/mp4 |
ISO Common Encryption Protection Scheme for ISO Base Media File Format Stream Format [EME-STREAM-MP4] |
|
audio/webm
video/webm |
WebM Stream Format [EME-STREAM-WEBM] |