VideoDecoder: configure() method

Secure contextAvailable in workers

The configure() method of the VideoDecoder interface enqueues a control message to configure the video decoder for decoding chunks.

Syntax

configure(config)

Parameters

• config
  • : An object containing the following members:
    • codec
      • : A string containing a valid codec string. See “codecs” parameter for details on codec string construction.
    • description Optional
      • : An ArrayBuffer, a TypedArray, or a DataView containing a sequence of codec specific bytes, commonly known as extradata.
    • codedWidth Optional
      • : An integer representing the width of the VideoFrame in pixels, including any non-visible padding, before any ratio adjustments.
    • codedHeight Optional
      • : An integer representing the height of the VideoFrame in pixels, including any non-visible padding, before any ratio adjustments.
    • displayAspectWidth Optional
      • : An integer representing the horizontal dimension of the VideoFrame in pixels when displayed.
    • displayAspectHeight Optional
      • : An integer representing the vertical dimension of the VideoFrame in pixels when displayed.
    • colorSpace Optional
      • : An object representing a VideoColorSpace, containing the following members:
        • primaries
          • : A string representing the color gamut of the video sample. One of:
            • "bt709"
            • "bt470bg"
            • "smpte170m"
        • transfer
          • : A string representing transfer characteristics. One of:
            • "bt709"
            • "smpte170m"
            • "iec61966-2-1"
        • matrix
          • : A string representing a matrix coefficient. One of:
            • "rgb"
            • "bt709"
            • "bt470bg"
            • "smpte170m"
    • hardwareAcceleration Optional
      • : A hint as to the hardware acceleration method to use. One of:
        • "no-preference"
        • "prefer-hardware"
        • "prefer-software"
    • optimizeForLatency Optional
      • : A boolean. If true this is a hint that the selected decoder should be optimized to minimize the number of EncodedVideoChunk objects that have to be decoded before a VideoFrame is output.
    • flip Optional
      • : A boolean. If true, horizontal mirroring is applied. Defaults to false.
    • rotation Optional
      • : An integer representing the rotation (0, 90, 180, or 270) in degrees clockwise. Defaults to 0. Arbitrary numbers (including negatives) are rounded to the next quarter turn.

[!NOTE] The registrations in the WebCodecs Codec Registry link to a specification detailing whether and how to populate the optional description member.

Return value

None (undefined).

Exceptions

• TypeError
  • : Thrown if the provided config is invalid.
• InvalidStateError DOMException
  • : Thrown if the state is "closed".
• NotSupportedError DOMException
  • : Thrown if the provided config is valid but the user agent cannot provide a codec that can decode this profile.

Examples

The following example creates a new VideoDecoder and configures it with the "vp8" codec, a codedWidth of 640 pixels and a codedHeight of 480 pixels.

const init = {
  output: handleFrame,
  error(e) {
    console.log(e.message);
  },
};

const config = {
  codec: "vp8",
  codedWidth: 640,
  codedHeight: 480,
};

let decoder = new VideoDecoder(init);
decoder.configure(config);

Specifications

Browser compatibility

See also

• isConfigSupported()
• Codec String Support Table