fix(DASH): Fix manifest update time for LL-DASH (#5736)

shaka-project · Oct 11, 2023 · 8b7141f · 8b7141f
1 parent 01da5fa
commit 8b7141f
Show file tree

Hide file tree

Showing 8 changed files with 64 additions and 6 deletions.
diff --git a/externs/shaka/manifest_parser.js b/externs/shaka/manifest_parser.js
@@ -94,6 +94,14 @@ shaka.extern.ManifestParser = class {
    * @exportDoc
    */
   onExpirationUpdated(sessionId, expiration) {}
+
+  /**
+   * Tell the parser that the initial variant has been chosen.
+   *
+   * @param {shaka.extern.Variant} variant
+   * @exportDoc
+   */
+  onInitialVariantChosen(variant) {}
 };
 
 

diff --git a/lib/dash/dash_parser.js b/lib/dash/dash_parser.js
@@ -212,6 +212,31 @@ shaka.dash.DashParser = class {
     // No-op
   }
 
+  /**
+   * @override
+   * @exportInterface
+   */
+  onInitialVariantChosen(variant) {
+    if (this.manifest_ && this.lowLatencyMode_ &&
+        this.minTotalAvailabilityTimeOffset_) {
+      const stream = variant.video || variant.audio;
+      if (stream && stream.segmentIndex) {
+        const availabilityEnd =
+            this.manifest_.presentationTimeline.getSegmentAvailabilityEnd();
+        const position = stream.segmentIndex.find(availabilityEnd);
+        if (position == null) {
+          return;
+        }
+        const reference = stream.segmentIndex.get(position);
+        if (!reference) {
+          return;
+        }
+        this.updatePeriod_ = reference.endTime - availabilityEnd;
+        this.setUpdateTimer_(/* offset= */ 0);
+      }
+    }
+  }
+
   /**
    * Makes a network request for the manifest and parses the resulting data.
    *
@@ -496,12 +521,6 @@ shaka.dash.DashParser = class {
       minBufferTime = 0;
     }
 
-    // Set updatePeriod_ to minTotalAvailabilityTimeOffset_ to achieve the best
-    // latency in LL streams
-    if (this.lowLatencyMode_ && this.minTotalAvailabilityTimeOffset_) {
-      this.updatePeriod_ = this.minTotalAvailabilityTimeOffset_;
-    }
-
     // These steps are not done on manifest update.
     if (!this.manifest_) {
       this.manifest_ = {

diff --git a/lib/hls/hls_parser.js b/lib/hls/hls_parser.js
@@ -474,6 +474,14 @@ shaka.hls.HlsParser = class {
     // No-op
   }
 
+  /**
+   * @override
+   * @exportInterface
+   */
+  onInitialVariantChosen(variant) {
+    // No-op
+  }
+
   /**
    * Align the streams by sequence number by dropping early segments.  Then
    * offset the streams to begin at presentation time 0.

diff --git a/lib/mss/mss_parser.js b/lib/mss/mss_parser.js
@@ -213,6 +213,14 @@ shaka.mss.MssParser = class {
     // No-op
   }
 
+  /**
+   * @override
+   * @exportInterface
+   */
+  onInitialVariantChosen(variant) {
+    // No-op
+  }
+
   /**
    * Makes a network request for the manifest and parses the resulting data.
    *

diff --git a/lib/offline/offline_manifest_parser.js b/lib/offline/offline_manifest_parser.js
@@ -112,6 +112,11 @@ shaka.offline.OfflineManifestParser = class {
       await muxer.destroy();
     }
   }
+
+  /** @override */
+  onInitialVariantChosen(variant) {
+    // No-op
+  }
 };
 
 

diff --git a/lib/player.js b/lib/player.js
@@ -2230,6 +2230,10 @@ shaka.Player = class extends shaka.util.FakeEventTarget {
       await Promise.all(createSegmentIndexPromises);
     }
 
+    if (this.parser_ && this.parser_.onInitialVariantChosen) {
+      this.parser_.onInitialVariantChosen(toLazyLoad);
+    }
+
     shaka.Player.applyPlayRange_(this.manifest_.presentationTimeline,
         this.config_.playRangeStart,
         this.config_.playRangeEnd);

diff --git a/test/offline/storage_integration.js b/test/offline/storage_integration.js
@@ -1742,6 +1742,9 @@ filterDescribe('Storage', storageSupport, () => {
 
     /** @override */
     onExpirationUpdated(session, number) {}
+
+    /** @override */
+    onInitialVariantChosen(variant) {}
   };
 
   /**

diff --git a/test/test/util/test_scheme.js b/test/test/util/test_scheme.js
@@ -763,6 +763,9 @@ shaka.test.TestScheme.ManifestParser = class {
 
   /** @override */
   onExpirationUpdated() {}
+
+  /** @override */
+  onInitialVariantChosen() {}
 };