Inline a patched version of WebCodecs types

Author: robintown

knip.ts

@@ -27,10 +27,6 @@ export default {
     // then Knip will flag it as a false positive
     // https://github.com/webpro-nl/knip/issues/766
     "@vector-im/compound-web",
-    // We need this so the eslint is happy with @livekit/track-processors.
-    // This might be a bug in the livekit repo but for now we fix it on the
-    // element call side.
-    "@types/dom-mediacapture-transform",
     "matrix-widget-api",
   ],
   ignoreExportsUsedInFile: true,

package.json

@@ -62,7 +62,6 @@
     "@testing-library/react": "^16.0.0",
     "@testing-library/user-event": "^14.5.1",
     "@types/content-type": "^1.1.5",
-    "@types/dom-mediacapture-transform": "^0.1.10",
     "@types/grecaptcha": "^3.0.9",
     "@types/jsdom": "^21.1.7",
     "@types/lodash-es": "^4.17.12",

src/@types/dom-mediacapture-transform.d.ts

@@ -0,0 +1,137 @@
+/* eslint-disable */
+// The contents of this file below the line are copied from
+// @types/dom-mediacapture-transform, which is inlined here into Element Call so
+// that we can apply the patch to @types/dom-webcodecs found in
+// ./dom-webcodecs.d.ts, which it depends on.
+// (https://github.com/DefinitelyTyped/DefinitelyTyped/pull/72625)
+// Once that PR is merged and released, we can remove this file and return to
+// depending on @types/dom-mediacapture-transform.
+// -----------------------------------------------------------------------------
+
+// In general, these types are only available behind a command line flag or an origin trial in
+// Chrome 90+.
+
+// This API depends on WebCodecs.
+
+// Versioning:
+// Until the above-mentioned spec is finalized, the major version number is 0. Although not
+// necessary for version 0, consider incrementing the minor version number for breaking changes.
+
+// The following modify existing DOM types to allow defining type-safe APIs on audio and video tracks.
+
+/** Specialize MediaStreamTrack so that we can refer specifically to an audio track. */
+interface MediaStreamAudioTrack extends MediaStreamTrack {
+  readonly kind: "audio";
+  clone(): MediaStreamAudioTrack;
+}
+
+/** Specialize MediaStreamTrack so that we can refer specifically to a video track. */
+interface MediaStreamVideoTrack extends MediaStreamTrack {
+  readonly kind: "video";
+  clone(): MediaStreamVideoTrack;
+}
+
+/** Assert that getAudioTracks and getVideoTracks return the tracks with the appropriate kind. */
+interface MediaStream {
+  getAudioTracks(): MediaStreamAudioTrack[];
+  getVideoTracks(): MediaStreamVideoTrack[];
+}
+
+// The following were originally generated from the spec using
+// https://github.com/microsoft/TypeScript-DOM-lib-generator, then heavily modified.
+
+/**
+ * A track sink that is capable of exposing the unencoded frames from the track to a
+ * ReadableStream, and exposes a control channel for signals going in the oppposite direction.
+ */
+interface MediaStreamTrackProcessor<T extends AudioData | VideoFrame> {
+  /**
+   * Allows reading the frames flowing through the MediaStreamTrack provided to the constructor.
+   */
+  readonly readable: ReadableStream<T>;
+  /** Allows sending control signals to the MediaStreamTrack provided to the constructor. */
+  readonly writableControl: WritableStream<MediaStreamTrackSignal>;
+}
+
+declare var MediaStreamTrackProcessor: {
+  prototype: MediaStreamTrackProcessor<any>;
+
+  /** Constructor overrides based on the type of track. */
+  new (
+    init: MediaStreamTrackProcessorInit & { track: MediaStreamAudioTrack },
+  ): MediaStreamTrackProcessor<AudioData>;
+  new (
+    init: MediaStreamTrackProcessorInit & { track: MediaStreamVideoTrack },
+  ): MediaStreamTrackProcessor<VideoFrame>;
+};
+
+interface MediaStreamTrackProcessorInit {
+  track: MediaStreamTrack;
+  /**
+   * If media frames are not read from MediaStreamTrackProcessor.readable quickly enough, the
+   * MediaStreamTrackProcessor will internally buffer up to maxBufferSize of the frames produced
+   * by the track. If the internal buffer is full, each time the track produces a new frame, the
+   * oldest frame in the buffer will be dropped and the new frame will be added to the buffer.
+   */
+  maxBufferSize?: number | undefined;
+}
+
+/**
+ * Takes video frames as input, and emits control signals that result from subsequent processing.
+ */
+interface MediaStreamTrackGenerator<T extends AudioData | VideoFrame>
+  extends MediaStreamTrack {
+  /**
+   * Allows writing media frames to the MediaStreamTrackGenerator, which is itself a
+   * MediaStreamTrack. When a frame is written to writable, the frame’s close() method is
+   * automatically invoked, so that its internal resources are no longer accessible from
+   * JavaScript.
+   */
+  readonly writable: WritableStream<T>;
+  /**
+   * Allows reading control signals sent from any sinks connected to the
+   * MediaStreamTrackGenerator.
+   */
+  readonly readableControl: ReadableStream<MediaStreamTrackSignal>;
+}
+
+type MediaStreamAudioTrackGenerator = MediaStreamTrackGenerator<AudioData> &
+  MediaStreamAudioTrack;
+type MediaStreamVideoTrackGenerator = MediaStreamTrackGenerator<VideoFrame> &
+  MediaStreamVideoTrack;
+
+declare var MediaStreamTrackGenerator: {
+  prototype: MediaStreamTrackGenerator<any>;
+
+  /** Constructor overrides based on the type of track. */
+  new (
+    init: MediaStreamTrackGeneratorInit & {
+      kind: "audio";
+      signalTarget?: MediaStreamAudioTrack | undefined;
+    },
+  ): MediaStreamAudioTrackGenerator;
+  new (
+    init: MediaStreamTrackGeneratorInit & {
+      kind: "video";
+      signalTarget?: MediaStreamVideoTrack | undefined;
+    },
+  ): MediaStreamVideoTrackGenerator;
+};
+
+interface MediaStreamTrackGeneratorInit {
+  kind: MediaStreamTrackGeneratorKind;
+  /**
+   * (Optional) track to which the MediaStreamTrackGenerator will automatically forward control
+   * signals. If signalTarget is provided and signalTarget.kind and kind do not match, the
+   * MediaStreamTrackGenerator’s constructor will raise an exception.
+   */
+  signalTarget?: MediaStreamTrack | undefined;
+}
+
+type MediaStreamTrackGeneratorKind = "audio" | "video";
+
+type MediaStreamTrackSignalType = "request-frame";
+
+interface MediaStreamTrackSignal {
+  signalType: MediaStreamTrackSignalType;
+}