fix: Fix nalu parsing in TS (#6137)

Fixes #6136
shaka-project · Jan 22, 2024 · df8dbb9 · df8dbb9
1 parent 2ae9ca6
commit df8dbb9
Showing 1 changed file with 7 additions and 4 deletions.
diff --git a/lib/util/ts_parser.js b/lib/util/ts_parser.js
@@ -446,10 +446,11 @@ shaka.util.TsParser = class {
    *
    * @param {shaka.extern.MPEG_PES} pes
    * @param {?shaka.extern.VideoNalu=} lastNalu
+   * @param {?number=} lastState
    * @return {!Array.<shaka.extern.VideoNalu>}
    * @export
    */
-  parseNalus(pes, lastNalu) {
+  parseNalus(pes, lastNalu, lastState) {
     const timescale = shaka.util.TsParser.Timescale;
     const time = pes.pts ? pes.pts / timescale : null;
     const data = pes.data;
@@ -465,7 +466,7 @@ shaka.util.TsParser = class {
     // precede each NALU. A start code is 2 or 3 0x00 bytes followed with a
     // 0x01 byte. e.g. 0x000001 or 0x00000001.
     // More info in: https://stackoverflow.com/questions/24884827/possible-locations-for-sequence-picture-parameter-sets-for-h-264-stream/24890903#24890903
-    let numZeros = 0;
+    let numZeros = lastState || 0;
 
     /** @type {!Array.<shaka.extern.VideoNalu>} */
     const nalus = [];
@@ -490,7 +491,7 @@ shaka.util.TsParser = class {
           const startCodeSize = numZeros > 3 ? 3 : numZeros;
           const lastByteToKeep = i - startCodeSize;
           // Optimization
-          if (lastByteToKeep != 0) {
+          if (lastState && lastByteToKeep != 0) {
             const prevData = data.subarray(0, lastByteToKeep);
             lastNalu.data = shaka.util.Uint8ArrayUtils.concat(
                 lastNalu.data, prevData);
@@ -572,6 +573,7 @@ shaka.util.TsParser = class {
       lastNalu.fullData = shaka.util.Uint8ArrayUtils.concat(
           lastNalu.fullData, data);
     }
+    lastState = Math.min(3, numZeros);
     return nalus;
   }
 
@@ -676,8 +678,9 @@ shaka.util.TsParser = class {
       }
       if (naluProcessing) {
         let lastNalu;
+        let lastState;
         for (const pes of this.videoPes_) {
-          pes.nalus = this.parseNalus(pes, lastNalu);
+          pes.nalus = this.parseNalus(pes, lastNalu, lastState);
           if (pes.nalus.length) {
             lastNalu = pes.nalus[pes.nalus.length - 1];
           }