feat(HLS): Add new config for allow LL-HLS byterange optimization (#5877

)
shaka-project · Nov 13, 2023 · 3e91e8e · 3e91e8e
1 parent f5777e5
commit 3e91e8e
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Showing 4 changed files with 12 additions and 2 deletions.
diff --git a/demo/config.js b/demo/config.js
@@ -211,6 +211,8 @@ shakaDemo.Config = class {
             'manifest.hls.ignoreManifestTimestampsInSegmentsMode')
         .addBoolInput_('Disable codec guessing',
             'manifest.hls.disableCodecGuessing')
+        .addBoolInput_('Allow LL-HLS byterange optimization',
+            'manifest.hls.allowLowLatencyByteRangeOptimization')
         .addNumberInput_('Availability Window Override',
             'manifest.availabilityWindowOverride',
             /* canBeDecimal= */ true,

diff --git a/externs/shaka/player.js b/externs/shaka/player.js
@@ -934,7 +934,8 @@ shaka.extern.DashManifestConfiguration;
  *   liveSegmentsDelay: number,
  *   sequenceMode: boolean,
  *   ignoreManifestTimestampsInSegmentsMode: boolean,
- *   disableCodecGuessing: boolean
+ *   disableCodecGuessing: boolean,
+ *   allowLowLatencyByteRangeOptimization: boolean
  * }}
  *
  * @property {boolean} ignoreTextStreamFailures
@@ -994,6 +995,11 @@ shaka.extern.DashManifestConfiguration;
  *   As a consequence, lazy-loading media playlists won't be possible for this
  *   use case, which may result in longer video startup times.
  *   <i>Defaults to <code>false</code>.</i>
+ * @property {boolean} allowLowLatencyByteRangeOptimization
+ *   If set to true, the HLS parser will optimize operation with LL and partial
+ *   byte range segments. More info in
+ *   https://www.akamai.com/blog/performance/-using-ll-hls-with-byte-range-addressing-to-achieve-interoperabi
+ *   <i>Defaults to <code>true</code>.</i>
  * @exportDoc
  */
 shaka.extern.HlsManifestConfiguration;

diff --git a/lib/hls/hls_parser.js b/lib/hls/hls_parser.js
@@ -2941,7 +2941,8 @@ shaka.hls.HlsParser = class {
 
     if (this.lowLatencyMode_ && hlsSegment.partialSegments.length) {
       const byterangeOptimizationSupport = (stream.mimeType == 'video/mp4' ||
-          stream.mimeType == 'audio/mp4') && window.ReadableStream;
+          stream.mimeType == 'audio/mp4') && window.ReadableStream &&
+          this.config_.hls.allowLowLatencyByteRangeOptimization;
 
       let partialSyncTime = syncTime;
       for (let i = 0; i < hlsSegment.partialSegments.length; i++) {

diff --git a/lib/util/player_configuration.js b/lib/util/player_configuration.js
@@ -150,6 +150,7 @@ shaka.util.PlayerConfiguration = class {
         sequenceMode: shaka.util.Platform.supportsSequenceMode(),
         ignoreManifestTimestampsInSegmentsMode: false,
         disableCodecGuessing: false,
+        allowLowLatencyByteRangeOptimization: true,
       },
       mss: {
         manifestPreprocessor: (element) => {