fix: Fix ts parser when using B-frames (#8696)

Fixes #8691

Author: avelad

karma.conf.js

@@ -287,6 +287,7 @@ module.exports = (config) => {
       {pattern: 'test/test/assets/hls-text-offset/*', included: false},
       {pattern: 'test/test/assets/hls-ts-aac/*', included: false},
       {pattern: 'test/test/assets/hls-ts-ac3/*', included: false},
+      {pattern: 'test/test/assets/hls-ts-b-frames/*', included: false},
       {pattern: 'test/test/assets/hls-ts-ec3/*', included: false},
       {pattern: 'test/test/assets/hls-ts-h264/*', included: false},
       {pattern: 'test/test/assets/hls-ts-h265/*', included: false},

lib/util/ts_parser.js

@@ -485,7 +485,11 @@ shaka.util.TsParser = class {
           this.referenceDts_ = dts;
         }
 
-        pes.dts = this.handleRollover_(dts, this.referenceDts_);
+        if (pes.pts != pts) {
+          pes.dts = this.handleRollover_(dts, this.referenceDts_);
+        } else {
+          pes.dts = dts;
+        }
       }
       this.referenceDts_ = pes.dts;
     }
@@ -767,7 +771,9 @@ shaka.util.TsParser = class {
             this.videoPes_[this.videoPes_.length - 1] : null;
         if (pes && pes.pts != null && pes.dts != null && (!previousPes ||
             (previousPes.pts != pes.pts && previousPes.dts != pes.dts))) {
-          if (this.videoPes_.length && pes.dts < (previousPes.dts || 0)) {
+          if (previousPes && this.videoPes_.length &&
+              pes.dts < (previousPes.dts || pes.dts) &&
+              pes.pts < (previousPes.pts || pes.pts)) {
             sort = true;
           }
           this.videoPes_.push(pes);

test/test/assets/hls-ts-b-frames/1.ts

@@ -0,0 +1,6 @@
+#EXTM3U
+#EXT-X-VERSION:4
+#EXT-X-INDEPENDENT-SEGMENTS
+
+#EXT-X-STREAM-INF:BANDWIDTH=857405,AVERAGE-BANDWIDTH=857405,RESOLUTION=1280x720,CODECS="avc1.64001F",FRAME-RATE=25
+playlist.m3u8

test/test/assets/hls-ts-b-frames/index.m3u8

@@ -0,0 +1,8 @@
+#EXTM3U
+#EXT-X-VERSION:3
+#EXT-X-MEDIA-SEQUENCE:1
+#EXT-X-TARGETDURATION:6
+#EXT-X-PLAYLIST-TYPE:VOD
+#EXTINF:5.760,
+1.ts
+#EXT-X-ENDLIST

test/test/assets/hls-ts-b-frames/playlist.m3u8

@@ -253,6 +253,17 @@ describe('Transmuxer Player', () => {
       await player.unload();
     });
 
+    it('H.264 in TS with b-frames', async () => {
+      await player.load('/base/test/test/assets/hls-ts-b-frames/index.m3u8');
+      await video.play();
+      expect(player.isLive()).toBe(false);
+
+      // Play for 30 seconds, but stop early if the video ends.
+      await waiter.waitForEndOrTimeout(video, 30);
+
+      await player.unload();
+    });
+
     it('H.265 in TS', async () => {
       if (!await Util.isTypeSupported('video/mp4; codecs="hvc1.2.4.L123.B0"',
           /* width= */ 640, /* height= */ 360)) {