fix: account for multiple layers

GetStream · Dec 23, 2024 · b5cd7b7 · b5cd7b7
1 parent 9098cb4
commit b5cd7b7
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Showing 2 changed files with 40 additions and 3 deletions.
diff --git a/packages/client/src/rtc/__tests__/videoLayers.test.ts b/packages/client/src/rtc/__tests__/videoLayers.test.ts
@@ -193,7 +193,7 @@ describe('videoLayers', () => {
     });
   });
 
-  it('should map OptimalVideoLayer to SVC encodings', () => {
+  it('should map OptimalVideoLayer to SVC encodings (three layers)', () => {
     const layers: Array<Partial<OptimalVideoLayer>> = [
       { rid: 'f', width: 1920, height: 1080, maxBitrate: 3000000 },
       { rid: 'h', width: 960, height: 540, maxBitrate: 750000 },
@@ -210,6 +210,37 @@ describe('videoLayers', () => {
     });
   });
 
+  it('should map OptimalVideoLayer to SVC encodings (two layers)', () => {
+    const layers: Array<Partial<OptimalVideoLayer>> = [
+      { rid: 'h', width: 960, height: 540, maxBitrate: 750000 },
+      { rid: 'q', width: 480, height: 270, maxBitrate: 187500 },
+    ];
+
+    const svcLayers = toSvcEncodings(layers as OptimalVideoLayer[]);
+    expect(svcLayers.length).toBe(1);
+    expect(svcLayers[0]).toEqual({
+      rid: 'q',
+      width: 960,
+      height: 540,
+      maxBitrate: 750000,
+    });
+  });
+
+  it('should map OptimalVideoLayer to SVC encodings (two layers)', () => {
+    const layers: Array<Partial<OptimalVideoLayer>> = [
+      { rid: 'q', width: 480, height: 270, maxBitrate: 187500 },
+    ];
+
+    const svcLayers = toSvcEncodings(layers as OptimalVideoLayer[]);
+    expect(svcLayers.length).toBe(1);
+    expect(svcLayers[0]).toEqual({
+      rid: 'q',
+      width: 480,
+      height: 270,
+      maxBitrate: 187500,
+    });
+  });
+
   describe('getComputedMaxBitrate', () => {
     it('should scale target bitrate down if resolution is smaller than target resolution', () => {
       const targetResolution = { width: 1920, height: 1080, bitrate: 3000000 };

diff --git a/packages/client/src/rtc/videoLayers.ts b/packages/client/src/rtc/videoLayers.ts
@@ -29,8 +29,14 @@ const defaultBitratePerRid: Record<string, number> = {
 export const toSvcEncodings = (
   layers: OptimalVideoLayer[] | undefined,
 ): RTCRtpEncodingParameters[] | undefined => {
-  // we take the `f` layer, and we rename it to `q`.
-  return layers?.filter((l) => l.rid === 'f').map((l) => ({ ...l, rid: 'q' }));
+  if (!layers) return undefined;
+  // we take the highest quality layer, and we assign it to `q` encoder.
+  const withRid = (rid: string) => (l: OptimalVideoLayer) => l.rid === rid;
+  const highestLayer =
+    layers.find(withRid('f')) ||
+    layers.find(withRid('h')) ||
+    layers.find(withRid('q'));
+  return [{ ...highestLayer, rid: 'q' }];
 };
 
 /**