MediaStreamTrackProcessor.md

MediaStreamTrackProcessor

Namespace: SpawnDev.SpawnJS.JSObjects
Inherits: SpawnJSObject
Source: JSObjects/MediaStreamTrackProcessor.cs
MDN Reference: MediaStreamTrackProcessor on MDN

The MediaStreamTrackProcessor interface of the Insertable Streams for MediaStreamTrack API consumes a video MediaStreamTrack object's source and generates a stream of VideoFrame objects. https://developer.mozilla.org/en-US/docs/Web/API/MediaStreamTrackProcessor

Constructors

Signature	Description
MediaStreamTrackProcessor(MediaStreamTrackProcessorOptions options)	The MediaStreamTrackProcessor() constructor creates a new MediaStreamTrackProcessor object which consumes a video MediaStreamTrack object's source and generates a stream of VideoFrames.

Properties

Property	Type	Access	Description
Readable	ReadableStream	get	The readable property of the MediaStreamTrackProcessor interface returns a ReadableStream of VideoFrames.

Examples

SpawnDev.SpawnJS Mapping Note: The JavaScript examples below show the standard Web API usage. In SpawnDev.SpawnJS, the same API is available with C# conventions:

• Properties and methods use PascalCase (e.g., readyState becomes ReadyState)
• Events use ActionEvent with +=/-= (e.g., addEventListener("click", fn) becomes OnClick += handler)
• Async methods return Task<T> instead of Promise<T>
• Objects should be disposed with using statements
• Access via JS.Get<MediaStreamTrackProcessor>(...) or constructor new MediaStreamTrackProcessor(...)

const stream = await navigator.mediaDevices.getUserMedia({ video: true });
const [track] = stream.getVideoTracks();
const worker = new Worker("worker.js");
worker.postMessage({ track }, [track]);
const { data } = await new Promise((r) => {
  worker.onmessage = r;
});
video.srcObject = new MediaStream([data.track]);

onmessage = async ({ data: { track } }) => {
  const vtg = new VideoTrackGenerator();
  self.postMessage({ track: vtg.track }, [vtg.track]);
  const { readable } = new MediaStreamTrackProcessor({ track });
  await readable
    .pipeThrough(new TransformStream({ transform }))
    .pipeTo(vtg.writable);
};

See full example on MDN