shaka-project · theodab · Apr 4, 2024 · Apr 1, 2024 · Apr 2, 2024 · Apr 1, 2024
diff --git a/karma.conf.js b/karma.conf.js
@@ -243,6 +243,7 @@ module.exports = (config) => {
       {pattern: 'test/test/assets/hls-raw-ec3/*', included: false},
       {pattern: 'test/test/assets/hls-raw-mp3/*', included: false},
       {pattern: 'test/test/assets/hls-sample-aes/*', included: false},
+      {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-ec3/*', included: false},

diff --git a/lib/media/media_source_engine.js b/lib/media/media_source_engine.js
@@ -1195,6 +1195,12 @@ shaka.media.MediaSourceEngine = class {
       return;
     }
 
+    // Reset the promise in case the timestamp offset changed during
+    // a period/discontinuity transition.
+    if (contentType == ContentType.VIDEO) {
+      this.textSequenceModeOffset_ = new shaka.util.PublicPromise();
+    }
+
     // Queue an abort() to help MSE splice together overlapping segments.
     // We set appendWindowEnd when we change periods in DASH content, and the
     // period transition may result in overlap.

diff --git a/test/hls/hls_parser_integration.js b/test/hls/hls_parser_integration.js
@@ -104,4 +104,30 @@ describe('HlsParser', () => {
 
     await player.unload();
   });
+
+  it('supports text discontinuity', async () => {
+    if (!shaka.util.Platform.supportsSequenceMode()) {
+      pending('Sequence mode is not supported by the platform.');
+    }
+
+    player.configure('manifest.hls.ignoreManifestProgramDateTime', true);
+    player.setTextTrackVisibility(true);
+
+    await player.load('/base/test/test/assets/hls-text-offset/index.m3u8');
+    await video.play();
+
+    // Wait for last cue
+    await waiter.waitUntilPlayheadReachesOrFailOnTimeout(video, 7, 30);
+
+    const cues = video.textTracks[0].cues;
+    expect(cues.length).toBe(3);
+    expect(cues[0].startTime).toBeCloseTo(0, 0);
+    expect(cues[0].endTime).toBeCloseTo(2, 0);
+    expect(cues[1].startTime).toBeCloseTo(2, 0);
+    expect(cues[1].endTime).toBeCloseTo(4, 0);
+    expect(cues[2].startTime).toBeCloseTo(6, 0);
+    expect(cues[2].endTime).toBeCloseTo(8, 0);
+
+    await player.unload();
+  });
 });
diff --git a/test/test/assets/hls-text-offset/index.m3u8 b/test/test/assets/hls-text-offset/index.m3u8
@@ -0,0 +1,8 @@
+#EXTM3U
+#EXT-X-VERSION:7
+#EXT-X-INDEPENDENT-SEGMENTS
+
+#EXT-X-STREAM-INF:BANDWIDTH=728000,AVERAGE-BANDWIDTH=728000,RESOLUTION=640x360,CODECS="avc1.4d001e,mp4a.40.2",SUBTITLES="subs"
+playlist-video.m3u8
+
+#EXT-X-MEDIA:TYPE=SUBTITLES,GROUP-ID="subs",LANGUAGE="en-US",NAME="caption_webvtt_en_webvtt",AUTOSELECT=YES,DEFAULT=YES,FORCED=NO,URI="playlist-vtt.m3u8"
diff --git a/test/test/assets/hls-text-offset/playlist-video.m3u8 b/test/test/assets/hls-text-offset/playlist-video.m3u8
@@ -0,0 +1,22 @@
+#EXTM3U
+#EXT-X-VERSION:7
+#EXT-X-TARGETDURATION:2
+#EXT-X-MEDIA-SEQUENCE:0
+#EXT-X-DISCONTINUITY-SEQUENCE:0
+#EXT-X-PROGRAM-DATE-TIME:2024-03-05T23:17:07.364Z
+#EXTINF:2.000000
+video-069.ts
+#EXT-X-PROGRAM-DATE-TIME:2024-03-05T23:17:09.364Z
+#EXTINF:2.000000
+video-070.ts
+#EXT-X-PROGRAM-DATE-TIME:2024-03-05T23:17:11.364Z
+#EXTINF:1.583000
+video-071.ts
+#EXT-X-DISCONTINUITY
+#EXT-X-PROGRAM-DATE-TIME:2024-03-05T23:17:27.573Z
+#EXTINF:0.917000
+video-072.ts
+#EXT-X-PROGRAM-DATE-TIME:2024-03-05T23:17:28.490Z
+#EXTINF:2.000000
+video-073.ts
+#EXT-X-ENDLIST
diff --git a/test/test/assets/hls-text-offset/playlist-vtt.m3u8 b/test/test/assets/hls-text-offset/playlist-vtt.m3u8
@@ -0,0 +1,22 @@
+#EXTM3U
+#EXT-X-VERSION:7
+#EXT-X-TARGETDURATION:2
+#EXT-X-MEDIA-SEQUENCE:0
+#EXT-X-DISCONTINUITY-SEQUENCE:0
+#EXT-X-PROGRAM-DATE-TIME:2024-03-05T23:17:07.364Z
+#EXTINF:2.000000
+vtt-069.vtt
+#EXT-X-PROGRAM-DATE-TIME:2024-03-05T23:17:09.364Z
+#EXTINF:2.000000
+vtt-070.vtt
+#EXT-X-DISCONTINUITY
+#EXT-X-PROGRAM-DATE-TIME:2024-03-05T23:17:27.573Z
+#EXTINF:0.917000
+vtt-071.vtt
+#EXT-X-PROGRAM-DATE-TIME:2024-03-05T23:17:28.490Z
+#EXTINF:2.000000
+vtt-072.vtt
+#EXT-X-PROGRAM-DATE-TIME:2024-03-05T23:17:30.490Z
+#EXTINF:2.000000
+vtt-073.vtt
+#EXT-X-ENDLIST
diff --git a/test/test/assets/hls-text-offset/video-0000000069.ts b/test/test/assets/hls-text-offset/video-0000000069.ts
diff --git a/test/test/assets/hls-text-offset/video-0000000070.ts b/test/test/assets/hls-text-offset/video-0000000070.ts
diff --git a/test/test/assets/hls-text-offset/video-0000000071.ts b/test/test/assets/hls-text-offset/video-0000000071.ts
diff --git a/test/test/assets/hls-text-offset/video-0000000072.ts b/test/test/assets/hls-text-offset/video-0000000072.ts
diff --git a/test/test/assets/hls-text-offset/video-0000000073.ts b/test/test/assets/hls-text-offset/video-0000000073.ts
diff --git a/test/test/assets/hls-text-offset/video-069.ts b/test/test/assets/hls-text-offset/video-069.ts
diff --git a/test/test/assets/hls-text-offset/video-070.ts b/test/test/assets/hls-text-offset/video-070.ts
diff --git a/test/test/assets/hls-text-offset/video-071.ts b/test/test/assets/hls-text-offset/video-071.ts
diff --git a/test/test/assets/hls-text-offset/video-072.ts b/test/test/assets/hls-text-offset/video-072.ts
diff --git a/test/test/assets/hls-text-offset/video-073.ts b/test/test/assets/hls-text-offset/video-073.ts
diff --git a/test/test/assets/hls-text-offset/vtt-069.vtt b/test/test/assets/hls-text-offset/vtt-069.vtt
@@ -0,0 +1,5 @@
+WEBVTT
+X-TIMESTAMP-MAP=LOCAL:01:00:00.000,MPEGTS:324000000
+
+02:20.000 --> 02:22.000
+You're a jerk Tom!
diff --git a/test/test/assets/hls-text-offset/vtt-070.vtt b/test/test/assets/hls-text-offset/vtt-070.vtt
@@ -0,0 +1,5 @@
+WEBVTT
+X-TIMESTAMP-MAP=LOCAL:01:00:00.000,MPEGTS:324000000
+
+02:22.000 --> 02:24.000
+You're jealous of my robot hand! 
diff --git a/test/test/assets/hls-text-offset/vtt-071.vtt b/test/test/assets/hls-text-offset/vtt-071.vtt
@@ -0,0 +1,2 @@
+WEBVTT
+X-TIMESTAMP-MAP=LOCAL:01:00:00.000,MPEGTS:324000000
diff --git a/test/test/assets/hls-text-offset/vtt-072.vtt b/test/test/assets/hls-text-offset/vtt-072.vtt
@@ -0,0 +1,2 @@
+WEBVTT
+X-TIMESTAMP-MAP=LOCAL:01:00:00.000,MPEGTS:324000000
diff --git a/test/test/assets/hls-text-offset/vtt-073.vtt b/test/test/assets/hls-text-offset/vtt-073.vtt
@@ -0,0 +1,5 @@
+WEBVTT
+X-TIMESTAMP-MAP=LOCAL:01:00:00.000,MPEGTS:324000000
+
+00:03.500 --> 00:05.500
+cues after discontinuity