Apply PTSNormalize to ID3 and Text samples to handle timestamp rollover

src/remux/mp4-remuxer.js

@@ -755,7 +755,7 @@ class MP4Remuxer {
     this.remuxAudio(track, timeOffset, contiguous);
   }
 
-  remuxID3 (track) {
+  remuxID3 (track, timeOffset) {
     const length = track.samples.length;
     if (!length) {
       return;
@@ -768,8 +768,8 @@ class MP4Remuxer {
       const sample = track.samples[index];
       // setting id3 pts, dts to relative time
       // using this._initPTS and this._initDTS to calculate relative time
-      sample.pts = ((sample.pts - initPTS) / inputTimeScale);
-      sample.dts = ((sample.dts - initDTS) / inputTimeScale);
+      sample.pts = PTSNormalize(sample.pts - initPTS, timeOffset * inputTimeScale) / inputTimeScale;
+      sample.dts = PTSNormalize(sample.dts - initDTS, timeOffset * inputTimeScale) / inputTimeScale;
     }
     this.observer.trigger(Event.FRAG_PARSING_METADATA, {
       samples: track.samples
@@ -778,22 +778,21 @@ class MP4Remuxer {
     track.samples = [];
   }
 
-  remuxText (track) {
-    track.samples.sort(function (a, b) {
-      return (a.pts - b.pts);
-    });
-
-    let length = track.samples.length, sample;
+  remuxText (track, timeOffset) {
+    const length = track.samples.length;
     const inputTimeScale = track.inputTimeScale;
     const initPTS = this._initPTS;
     // consume samples
     if (length) {
       for (let index = 0; index < length; index++) {
-        sample = track.samples[index];
+        const sample = track.samples[index];
         // setting text pts, dts to relative time
         // using this._initPTS and this._initDTS to calculate relative time
-        sample.pts = ((sample.pts - initPTS) / inputTimeScale);
+        sample.pts = PTSNormalize(sample.pts - initPTS, timeOffset * inputTimeScale) / inputTimeScale;
       }
+      track.samples.sort(function (a, b) {
+        return (a.pts - b.pts);
+      });
       this.observer.trigger(Event.FRAG_PARSING_USERDATA, {
         samples: track.samples
       });