Remove CEA-6/708 support from DefaultSubtitleParserFactory

`Cea608Parser` and `Cea708Parser` don't currently work correctly on
their own without the re-ordering of input buffers implemented in
`CeaDecoder`, and it's not clear how we can properly do this re-ordering
during extraction. This change ensures that if 'parse subtitles
during extraction' is enabled, CEA-6/708 subs will be passed through
without transcoding and can then be decoded during rendering by
`Cea6/708Decoder`.

PiperOrigin-RevId: 595658628

libraries/extractor/src/main/java/androidx/media3/extractor/text/DefaultSubtitleParserFactory.java

@@ -20,8 +20,6 @@ import androidx.media3.common.Format;
 import androidx.media3.common.Format.CueReplacementBehavior;
 import androidx.media3.common.MimeTypes;
 import androidx.media3.common.util.UnstableApi;
-import androidx.media3.extractor.text.cea.Cea608Parser;
-import androidx.media3.extractor.text.cea.Cea708Parser;
 import androidx.media3.extractor.text.dvb.DvbParser;
 import androidx.media3.extractor.text.pgs.PgsParser;
 import androidx.media3.extractor.text.ssa.SsaParser;
@@ -46,8 +44,6 @@ import java.util.Objects;
  *   <li>PGS ({@link PgsParser})
  *   <li>DVB ({@link DvbParser})
  *   <li>TTML ({@link TtmlParser})
- *   <li>CEA-608 ({@link Cea608Parser})
- *   <li>CEA-708 ({@link Cea708Parser})
  * </ul>
  */
 @UnstableApi
@@ -63,10 +59,7 @@ public final class DefaultSubtitleParserFactory implements SubtitleParser.Factor
         || Objects.equals(mimeType, MimeTypes.APPLICATION_TX3G)
         || Objects.equals(mimeType, MimeTypes.APPLICATION_PGS)
         || Objects.equals(mimeType, MimeTypes.APPLICATION_DVBSUBS)
-        || Objects.equals(mimeType, MimeTypes.APPLICATION_TTML)
+        || Objects.equals(mimeType, MimeTypes.APPLICATION_TTML);
-        || Objects.equals(mimeType, MimeTypes.APPLICATION_MP4CEA608)
-        || Objects.equals(mimeType, MimeTypes.APPLICATION_CEA608)
-        || Objects.equals(mimeType, MimeTypes.APPLICATION_CEA708);
   }
 
   @Override
@@ -90,11 +83,6 @@ public final class DefaultSubtitleParserFactory implements SubtitleParser.Factor
           return DvbParser.CUE_REPLACEMENT_BEHAVIOR;
         case MimeTypes.APPLICATION_TTML:
           return TtmlParser.CUE_REPLACEMENT_BEHAVIOR;
-        case MimeTypes.APPLICATION_MP4CEA608:
-        case MimeTypes.APPLICATION_CEA608:
-          return Cea608Parser.CUE_REPLACEMENT_BEHAVIOR;
-        case MimeTypes.APPLICATION_CEA708:
-          return Cea708Parser.CUE_REPLACEMENT_BEHAVIOR;
         default:
           break;
       }
@@ -123,17 +111,6 @@ public final class DefaultSubtitleParserFactory implements SubtitleParser.Factor
           return new DvbParser(format.initializationData);
         case MimeTypes.APPLICATION_TTML:
           return new TtmlParser();
-        case MimeTypes.APPLICATION_MP4CEA608:
-        case MimeTypes.APPLICATION_CEA608:
-          // Deliberately pass a timeout longer than Cea608Parser.MIN_DATA_CHANNEL_TIMEOUT_MS
-          // because Cea608Parser erases 'stuck' cues starting from their start time, rather than
-          // the last piece of CEA data received.
-          return new Cea608Parser(
-              mimeType,
-              format.accessibilityChannel,
-              /* validDataChannelTimeoutMs= */ 2 * Cea608Parser.MIN_DATA_CHANNEL_TIMEOUT_MS);
-        case MimeTypes.APPLICATION_CEA708:
-          return new Cea708Parser(format.accessibilityChannel, format.initializationData);
         default:
           break;
       }

libraries/extractor/src/main/java/androidx/media3/extractor/text/cea/Cea608Parser.java

@@ -47,6 +47,9 @@ import java.util.Collections;
 import java.util.List;
 
 /** A {@link SubtitleParser} for CEA-608 (also known as "line 21 captions" and "EIA-608"). */
+// TODO: b/317488646 - Either re-combine this with Cea608Decoder (if we decide that decoding this
+//  format must happen during rendering), or re-add it to DefaultSubtitleParserFactory (if we're
+//  able to solve the re-ordering issue during extraction).
 @UnstableApi
 public final class Cea608Parser implements SubtitleParser {
 

libraries/extractor/src/main/java/androidx/media3/extractor/text/cea/Cea708Parser.java

@@ -48,6 +48,9 @@ import java.util.List;
 import org.checkerframework.checker.nullness.qual.RequiresNonNull;
 
 /** A {@link SubtitleParser} for CEA-708 (also known as "EIA-708"). */
+// TODO: b/317488646 - Either re-combine this with Cea708Decoder (if we decide that decoding this
+//  format must happen during rendering), or re-add it to DefaultSubtitleParserFactory (if we're
+//  able to solve the re-ordering issue during extraction).
 @UnstableApi
 public final class Cea708Parser implements SubtitleParser {