Migrate CEA-708 logic to a SubtitleParser implementation

This change is similar to 27caeb8038 (CEA-608), but is currently lacking unit tests.

PiperOrigin-RevId: 582585457

libraries/exoplayer/src/main/java/androidx/media3/exoplayer/text/SubtitleDecoderFactory.java

@@ -17,15 +17,10 @@ package androidx.media3.exoplayer.text;
 
 import androidx.annotation.Nullable;
 import androidx.media3.common.Format;
-import androidx.media3.common.MimeTypes;
 import androidx.media3.common.util.UnstableApi;
 import androidx.media3.extractor.text.DefaultSubtitleParserFactory;
 import androidx.media3.extractor.text.SubtitleDecoder;
 import androidx.media3.extractor.text.SubtitleParser;
-import androidx.media3.extractor.text.cea.Cea608Decoder;
-import androidx.media3.extractor.text.cea.Cea608Parser;
-import androidx.media3.extractor.text.cea.Cea708Decoder;
-import java.util.Objects;
 
 /** A factory for {@link SubtitleDecoder} instances. */
 @UnstableApi
@@ -52,12 +47,7 @@ public interface SubtitleDecoderFactory {
   /**
    * Default {@link SubtitleDecoderFactory} implementation.
    *
-   * <p>Supports formats supported by {@link DefaultSubtitleParserFactory} as well as the following:
-   *
-   * <ul>
-   *   <li>Cea608 ({@link Cea608Decoder})
-   *   <li>Cea708 ({@link Cea708Decoder})
-   * </ul>
+   * <p>Only supports formats supported by {@link DefaultSubtitleParserFactory}.
    */
   SubtitleDecoderFactory DEFAULT =
       new SubtitleDecoderFactory() {
@@ -66,11 +56,7 @@ public interface SubtitleDecoderFactory {
 
         @Override
         public boolean supportsFormat(Format format) {
-          @Nullable String mimeType = format.sampleMimeType;
-          return delegate.supportsFormat(format)
-              || Objects.equals(mimeType, MimeTypes.APPLICATION_CEA608)
-              || Objects.equals(mimeType, MimeTypes.APPLICATION_MP4CEA608)
-              || Objects.equals(mimeType, MimeTypes.APPLICATION_CEA708);
+          return delegate.supportsFormat(format);
         }
 
         @Override
@@ -81,21 +67,6 @@ public interface SubtitleDecoderFactory {
                 subtitleParser.getClass().getSimpleName() + "Decoder", subtitleParser);
           }
           @Nullable String mimeType = format.sampleMimeType;
-          if (mimeType != null) {
-            switch (mimeType) {
-              case MimeTypes.APPLICATION_CEA608:
-              case MimeTypes.APPLICATION_MP4CEA608:
-                return new Cea608Decoder(
-                    new Cea608Parser(
-                        mimeType,
-                        format.accessibilityChannel,
-                        Cea608Parser.MIN_DATA_CHANNEL_TIMEOUT_MS));
-              case MimeTypes.APPLICATION_CEA708:
-                return new Cea708Decoder(format.accessibilityChannel, format.initializationData);
-              default:
-                break;
-            }
-          }
           throw new IllegalArgumentException(
               "Attempted to create decoder for unsupported MIME type: " + mimeType);
         }

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

@@ -21,6 +21,7 @@ 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;
@@ -46,6 +47,7 @@ import java.util.Objects;
  *   <li>DVB ({@link DvbParser})
  *   <li>TTML ({@link TtmlParser})
  *   <li>CEA-608 ({@link Cea608Parser})
+ *   <li>CEA-708 ({@link Cea708Parser})
  * </ul>
  */
 @UnstableApi
@@ -63,7 +65,8 @@ public final class DefaultSubtitleParserFactory implements SubtitleParser.Factor
         || Objects.equals(mimeType, MimeTypes.APPLICATION_DVBSUBS)
         || Objects.equals(mimeType, MimeTypes.APPLICATION_TTML)
         || Objects.equals(mimeType, MimeTypes.APPLICATION_MP4CEA608)
-        || Objects.equals(mimeType, MimeTypes.APPLICATION_CEA608);
+        || Objects.equals(mimeType, MimeTypes.APPLICATION_CEA608)
+        || Objects.equals(mimeType, MimeTypes.APPLICATION_CEA708);
   }
 
   @Override
@@ -90,6 +93,8 @@ public final class DefaultSubtitleParserFactory implements SubtitleParser.Factor
         case MimeTypes.APPLICATION_MP4CEA608:
         case MimeTypes.APPLICATION_CEA608:
           return Cea608Parser.CUE_REPLACEMENT_BEHAVIOR;
+        case MimeTypes.APPLICATION_CEA708:
+          return Cea708Parser.CUE_REPLACEMENT_BEHAVIOR;
         default:
           break;
       }
@@ -127,6 +132,8 @@ public final class DefaultSubtitleParserFactory implements SubtitleParser.Factor
               mimeType,
               format.accessibilityChannel,
               /* validDataChannelTimeoutMs= */ 2 * Cea608Parser.MIN_DATA_CHANNEL_TIMEOUT_MS);
+        case MimeTypes.APPLICATION_CEA708:
+          return new Cea708Parser(format.accessibilityChannel, format.initializationData);
         default:
           break;
       }