WebCodecs

Status of this document

This specification was published by the Web Platform Incubator Community Group. It is not a W3C Standard nor is it on the W3C Standards Track. Please note that under the W3C Community Contributor License Agreement (CLA) there is a limited opt-out and other conditions apply. Learn more about W3C Community and Business Groups.

1. Introduction

This section is non-normative

The introduction has not yet been written.

NOTE: The interfaces that follow are a work in progress.

2. VideoDecoder Interface

[Exposed=(Window)]
interface VideoDecoder {
    Promise<void> Initialize(VideoDecoderInitParameters params);
    Promise<void> Flush();
    void Close();

    readonly attribute WritableStream writable;  // of EncodedVideoFrame
    readonly attribute ReadableStream readable;  // of VideoFrame
};

[Exposed=(Window)]
dictionary VideoDecoderInitParameters {
  required DOMString codec;
  required DOMString profile;

  // These are the "coded size", not the "visible size"
  required unsigned long width;
  required unsigned long height;
};

3. VideoEncoder Interface

[Exposed=(Window)]
interface VideoEncoder {
  Promise<void> Initialize(VideoEncoderInitParameters params);
  void Close();

  readonly attribute WritableStream writable;  // of VideoFrame
  readonly attribute ReadableStream readable;  // of EncodedVideoFrame
};

enum VideoEncoderHardwareMode {
  "hardware",
  "software"
};

[Exposed=(Window)]
dictionary VideoEncoderInitParameters {
  required VideoEncoderHardwareMode hardware_mode;
  required DOMString codec;
  required DOMString profile;

  required unsigned long visible_width;
  required unsigned long visible_height;

  required unsigned long bitsPerSecond;
  required double framesPerSecond;

  required double maxFramesBetweenKeyFrames;
};

Conformance

Conformance requirements are expressed with a combination of descriptive assertions and RFC 2119 terminology. The key words “MUST”, “MUST NOT”, “REQUIRED”, “SHALL”, “SHALL NOT”, “SHOULD”, “SHOULD NOT”, “RECOMMENDED”, “MAY”, and “OPTIONAL” in the normative parts of this document are to be interpreted as described in RFC 2119. However, for readability, these words do not appear in all uppercase letters in this specification.

All of the text of this specification is normative except sections explicitly marked as non-normative, examples, and notes. [RFC2119]

Examples in this specification are introduced with the words “for example” or are set apart from the normative text with class="example", like this:

This is an example of an informative example.

Informative notes begin with the word “Note” and are set apart from the normative text with class="note", like this:

Note, this is an informative note.