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

PiperOrigin-RevId: 373343326

RELEASENOTES.md

@@ -18,6 +18,8 @@
         content being played
         ([#8776](https://github.com/google/ExoPlayer/issues/8776)).
 *   HLS
+    *   Use the `PRECISE` attribute in `EXT-X-START` to select the default start
+        position.
     *   Fix a bug where skipping into spliced-in chunks triggered an assertion
         error ([#8937](https://github.com/google/ExoPlayer/issues/8937).
 *   DRM:

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

@@ -393,9 +393,12 @@ public final class HlsMediaPlaylist extends HlsPlaylist {
    */
   @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
@@ -480,6 +483,7 @@ public final class HlsMediaPlaylist extends HlsPlaylist {
       String baseUri,
       List<String> tags,
       long startOffsetUs,
+      boolean preciseStart,
       long startTimeUs,
       boolean hasDiscontinuitySequence,
       int discontinuitySequence,
@@ -498,6 +502,7 @@ 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;
@@ -575,6 +580,7 @@ public final class HlsMediaPlaylist extends HlsPlaylist {
         baseUri,
         tags,
         startOffsetUs,
+        preciseStart,
         startTimeUs,
         /* hasDiscontinuitySequence= */ true,
         discontinuitySequence,
@@ -605,6 +611,7 @@ 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

@@ -208,6 +208,7 @@ 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 =
@@ -643,6 +644,7 @@ 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;
@@ -685,6 +687,8 @@ 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)) {
@@ -1015,6 +1019,7 @@ public final class HlsPlaylistParser implements ParsingLoadable.Parser<HlsPlayli
         baseUri,
         tags,
         startOffsetUs,
+        preciseStart,
         playlistStartTimeUs,
         hasDiscontinuitySequence,
         playlistDiscontinuitySequence,