MediaStreamTrackGenerator

Experimental: This is an experimental technology
Check the Browser compatibility table carefully before using this in production.

Non-standard: This feature is non-standard and is not on a standards track. Do not use it on production sites facing the Web: it will not work for every user. There may also be large incompatibilities between implementations and the behavior may change in the future.

The MediaStreamTrackGenerator interface of the Insertable Streams for MediaStreamTrack API creates a WritableStream that acts as a MediaStreamTrack source. The object consumes a stream of media frames as input, which can be audio or video frames.

Constructor

MediaStreamTrackGenerator() Experimental Non-standard: Creates a new MediaStreamTrackGenerator object which accepts either VideoFrame or AudioData objects.

Instance properties

This interface also inherits properties from MediaStreamTrack.

MediaStreamTrackGenerator.writable Experimental Non-standard: A WritableStream.

Instance methods

This interface doesn't implement any specific methods, but inherits methods from MediaStreamTrack.

Examples

The following example is from the article Insertable streams for MediaStreamTrack, and demonstrates a barcode scanner application, which process barcodes and highlights them before writing the transformed frames to the writable stream of MediaStreamTrackGenerator.writable.

const stream = await getUserMedia({ video: true });
const videoTrack = stream.getVideoTracks()[0];

const trackProcessor = new MediaStreamTrackProcessor({ track: videoTrack });
const trackGenerator = new MediaStreamTrackGenerator({ kind: "video" });

const transformer = new TransformStream({
  async transform(videoFrame, controller) {
    const barcodes = await detectBarcodes(videoFrame);
    const newFrame = highlightBarcodes(videoFrame, barcodes);
    videoFrame.close();
    controller.enqueue(newFrame);
  },
});

trackProcessor.readable
  .pipeThrough(transformer)
  .pipeTo(trackGenerator.writable);

Specifications

No specification found

No specification data found for api.MediaStreamTrackGenerator.
Check for problems with this page or contribute a missing spec_url to mdn/browser-compat-data. Also make sure the specification is included in w3c/browser-specs.

Browser compatibility

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