Merge pull request #8767 from uvjustin:hls-start-from-independent-part

PiperOrigin-RevId: 373343326

RELEASENOTES.md

@@ -41,6 +41,9 @@
 *   Ad playback:
     *   Support changing ad break positions in the player logic
         ([#5067](https://github.com/google/ExoPlayer/issues/5067).
+*   HLS
+    *   Use the PRECISE attribute in EXT-X-START to select the default start
+        position.
 
 ### 2.14.0 (2021-05-13)
 

library/hls/src/main/java/com/google/android/exoplayer2/source/hls/playlist/HlsMediaPlaylist.java

@@ -391,8 +391,13 @@ public final class HlsMediaPlaylist extends HlsPlaylist {
 
   /** The type of the playlist. See {@link PlaylistType}. */
   @PlaylistType public final int playlistType;
-  /** The start offset in microseconds, as defined by #EXT-X-START. */
+  /**
+   * The start offset in microseconds, as defined by #EXT-X-START, or {@link C#TIME_UNSET} if
+   * undefined.
+   */
   public final long startOffsetUs;
+  /** Whether the start position should be precise, as defined by #EXT-X-START. */
+  public final boolean preciseStart;
   /**
    * If {@link #hasProgramDateTime} is true, contains the datetime as microseconds since epoch.
    * Otherwise, contains the aggregated duration of removed segments up to this snapshot of the
@@ -467,6 +472,7 @@ public final class HlsMediaPlaylist extends HlsPlaylist {
       String baseUri,
       List<String> tags,
       long startOffsetUs,
+      boolean preciseStart,
       long startTimeUs,
       boolean hasDiscontinuitySequence,
       int discontinuitySequence,
@@ -485,6 +491,7 @@ public final class HlsMediaPlaylist extends HlsPlaylist {
     super(baseUri, tags, hasIndependentSegments);
     this.playlistType = playlistType;
     this.startTimeUs = startTimeUs;
+    this.preciseStart = preciseStart;
     this.hasDiscontinuitySequence = hasDiscontinuitySequence;
     this.discontinuitySequence = discontinuitySequence;
     this.mediaSequence = mediaSequence;
@@ -562,6 +569,7 @@ public final class HlsMediaPlaylist extends HlsPlaylist {
         baseUri,
         tags,
         startOffsetUs,
+        preciseStart,
         startTimeUs,
         /* hasDiscontinuitySequence= */ true,
         discontinuitySequence,
@@ -592,6 +600,7 @@ public final class HlsMediaPlaylist extends HlsPlaylist {
         baseUri,
         tags,
         startOffsetUs,
+        preciseStart,
         startTimeUs,
         hasDiscontinuitySequence,
         discontinuitySequence,

library/hls/src/main/java/com/google/android/exoplayer2/source/hls/playlist/HlsPlaylistParser.java

@@ -217,6 +217,7 @@ public final class HlsPlaylistParser implements ParsingLoadable.Parser<HlsPlayli
   private static final Pattern REGEX_FORCED = compileBooleanAttrPattern("FORCED");
   private static final Pattern REGEX_INDEPENDENT = compileBooleanAttrPattern("INDEPENDENT");
   private static final Pattern REGEX_GAP = compileBooleanAttrPattern("GAP");
+  private static final Pattern REGEX_PRECISE = compileBooleanAttrPattern("PRECISE");
   private static final Pattern REGEX_VALUE = Pattern.compile("VALUE=\"(.+?)\"");
   private static final Pattern REGEX_IMPORT = Pattern.compile("IMPORT=\"(.+?)\"");
   private static final Pattern REGEX_VARIABLE_REFERENCE =
@@ -652,6 +653,7 @@ public final class HlsPlaylistParser implements ParsingLoadable.Parser<HlsPlayli
     int relativeDiscontinuitySequence = 0;
     long playlistStartTimeUs = 0;
     long segmentStartTimeUs = 0;
+    boolean preciseStart = false;
     long segmentByteRangeOffset = 0;
     long segmentByteRangeLength = C.LENGTH_UNSET;
     long partStartTimeUs = 0;
@@ -694,6 +696,8 @@ public final class HlsPlaylistParser implements ParsingLoadable.Parser<HlsPlayli
         isIFrameOnly = true;
       } else if (line.startsWith(TAG_START)) {
         startOffsetUs = (long) (parseDoubleAttr(line, REGEX_TIME_OFFSET) * C.MICROS_PER_SECOND);
+        preciseStart =
+            parseOptionalBooleanAttribute(line, REGEX_PRECISE, /* defaultValue= */ false);
       } else if (line.startsWith(TAG_SERVER_CONTROL)) {
         serverControl = parseServerControl(line);
       } else if (line.startsWith(TAG_PART_INF)) {
@@ -1024,6 +1028,7 @@ public final class HlsPlaylistParser implements ParsingLoadable.Parser<HlsPlayli
         baseUri,
         tags,
         startOffsetUs,
+        preciseStart,
         playlistStartTimeUs,
         hasDiscontinuitySequence,
         playlistDiscontinuitySequence,