Add support for CEA608 in MP4 and fMP4

Issue: #1658
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=127312721

library/src/main/java/com/google/android/exoplayer2/extractor/mp4/Atom.java

@@ -117,6 +117,7 @@ import java.util.List;
   public static final int TYPE_tx3g = Util.getIntegerCodeForString("tx3g");
   public static final int TYPE_wvtt = Util.getIntegerCodeForString("wvtt");
   public static final int TYPE_stpp = Util.getIntegerCodeForString("stpp");
+  public static final int TYPE_c608 = Util.getIntegerCodeForString("c608");
   public static final int TYPE_samr = Util.getIntegerCodeForString("samr");
   public static final int TYPE_sawb = Util.getIntegerCodeForString("sawb");
   public static final int TYPE_udta = Util.getIntegerCodeForString("udta");

library/src/main/java/com/google/android/exoplayer2/extractor/mp4/AtomParsers.java

@@ -44,6 +44,7 @@ import java.util.List;
   private static final int TYPE_text = Util.getIntegerCodeForString("text");
   private static final int TYPE_sbtl = Util.getIntegerCodeForString("sbtl");
   private static final int TYPE_subt = Util.getIntegerCodeForString("subt");
+  private static final int TYPE_clcp = Util.getIntegerCodeForString("clcp");
 
   /**
    * Parses a trak atom (defined in 14496-12).
@@ -84,8 +85,8 @@ import java.util.List;
     Pair<long[], long[]> edtsData = parseEdts(trak.getContainerAtomOfType(Atom.TYPE_edts));
     return stsdData.format == null ? null
         : new Track(tkhdData.id, trackType, mdhdData.first, movieTimescale, durationUs,
-            stsdData.format, stsdData.trackEncryptionBoxes, stsdData.nalUnitLengthFieldLength,
-            edtsData.first, edtsData.second);
+            stsdData.format, stsdData.requiredSampleTransformation, stsdData.trackEncryptionBoxes,
+            stsdData.nalUnitLengthFieldLength, edtsData.first, edtsData.second);
   }
 
   /**
@@ -544,7 +545,8 @@ import java.util.List;
       return C.TRACK_TYPE_AUDIO;
     } else if (trackType == TYPE_vide) {
       return C.TRACK_TYPE_VIDEO;
-    } else if (trackType == TYPE_text || trackType == TYPE_sbtl || trackType == TYPE_subt) {
+    } else if (trackType == TYPE_text || trackType == TYPE_sbtl || trackType == TYPE_subt
+        || trackType == TYPE_clcp) {
       return C.TRACK_TYPE_TEXT;
     } else {
       return C.TRACK_TYPE_UNKNOWN;
@@ -621,6 +623,10 @@ import java.util.List;
         out.format = Format.createTextSampleFormat(Integer.toString(trackId),
             MimeTypes.APPLICATION_TTML, null, Format.NO_VALUE, 0, language, drmInitData,
             0 /* subsample timing is absolute */);
+      } else if (childAtomType == Atom.TYPE_c608) {
+        out.format = Format.createTextSampleFormat(Integer.toString(trackId),
+            MimeTypes.APPLICATION_EIA608, null, Format.NO_VALUE, 0, language, drmInitData);
+        out.requiredSampleTransformation = Track.TRANSFORMATION_CEA608_CDAT;
       }
       stsd.setPosition(childStartPosition + childAtomSize);
     }
@@ -1173,10 +1179,12 @@ import java.util.List;
 
     public Format format;
     public int nalUnitLengthFieldLength;
+    public int requiredSampleTransformation;
 
     public StsdData(int numberOfEntries) {
       trackEncryptionBoxes = new TrackEncryptionBox[numberOfEntries];
       nalUnitLengthFieldLength = -1;
+      requiredSampleTransformation = Track.TRANSFORMATION_NONE;
     }
 
   }

library/src/main/java/com/google/android/exoplayer2/extractor/mp4/FragmentedMp4Extractor.java

@@ -913,6 +913,10 @@ public final class FragmentedMp4Extractor implements Extractor {
       } else {
         sampleBytesWritten = 0;
       }
+      if (currentTrackBundle.track.sampleTransformation == Track.TRANSFORMATION_CEA608_CDAT) {
+        sampleSize -= Atom.HEADER_SIZE;
+        input.skipFully(Atom.HEADER_SIZE);
+      }
       parserState = STATE_READING_SAMPLE_CONTINUE;
       sampleCurrentNalBytesRemaining = 0;
     }

library/src/main/java/com/google/android/exoplayer2/extractor/mp4/Mp4Extractor.java

@@ -387,13 +387,19 @@ public final class Mp4Extractor implements Extractor, SeekMap {
     TrackOutput trackOutput = track.trackOutput;
     int sampleIndex = track.sampleIndex;
     long position = track.sampleTable.offsets[sampleIndex];
+    int sampleSize = track.sampleTable.sizes[sampleIndex];
+    if (track.track.sampleTransformation == Track.TRANSFORMATION_CEA608_CDAT) {
+      // The sample information is contained in a cdat atom. The header must be discarded for
+      // committing.
+      position += Atom.HEADER_SIZE;
+      sampleSize -= Atom.HEADER_SIZE;
+    }
     long skipAmount = position - input.getPosition() + sampleBytesWritten;
     if (skipAmount < 0 || skipAmount >= RELOAD_MINIMUM_SEEK_DISTANCE) {
       positionHolder.position = position;
       return RESULT_SEEK;
     }
     input.skipFully((int) skipAmount);
-    int sampleSize = track.sampleTable.sizes[sampleIndex];
     if (track.track.nalUnitLengthFieldLength != -1) {
       // Zero the top three bytes of the array that we'll use to parse nal unit lengths, in case
       // they're only 1 or 2 bytes long.

library/src/main/java/com/google/android/exoplayer2/extractor/mp4/Track.java

@@ -24,6 +24,15 @@ import com.google.android.exoplayer2.Format;
 public final class Track {
 
   /**
+   * A no-op sample transformation.
+   */
+  public static final int TRANSFORMATION_NONE = 0;
+  /**
+   * A transformation for caption samples in cdat atoms.
+   */
+  public static final int TRANSFORMATION_CEA608_CDAT = 1;
+
+  /**
    * The track identifier.
    */
   public final int id;
@@ -54,6 +63,12 @@ public final class Track {
   public final Format format;
 
   /**
+   * One of {@code TRANSFORMATION_*}. Defines the transformation to apply before outputting each
+   * sample.
+   */
+  public final int sampleTransformation;
+
+  /**
    * Track encryption boxes for the different track sample descriptions. Entries may be null.
    */
   public final TrackEncryptionBox[] sampleDescriptionEncryptionBoxes;
@@ -75,14 +90,16 @@ public final class Track {
   public final int nalUnitLengthFieldLength;
 
   public Track(int id, int type, long timescale, long movieTimescale, long durationUs,
-      Format format, TrackEncryptionBox[] sampleDescriptionEncryptionBoxes,
-      int nalUnitLengthFieldLength, long[] editListDurations, long[] editListMediaTimes) {
+      Format format, int sampleTransformation,
+      TrackEncryptionBox[] sampleDescriptionEncryptionBoxes, int nalUnitLengthFieldLength,
+      long[] editListDurations, long[] editListMediaTimes) {
     this.id = id;
     this.type = type;
     this.timescale = timescale;
     this.movieTimescale = movieTimescale;
     this.durationUs = durationUs;
     this.format = format;
+    this.sampleTransformation = sampleTransformation;
     this.sampleDescriptionEncryptionBoxes = sampleDescriptionEncryptionBoxes;
     this.nalUnitLengthFieldLength = nalUnitLengthFieldLength;
     this.editListDurations = editListDurations;

library/src/main/java/com/google/android/exoplayer2/extractor/ts/SeiReader.java

@@ -52,8 +52,26 @@ import com.google.android.exoplayer2.util.ParsableByteArray;
       } while (b == 0xFF);
       // Process the payload.
       if (Eia608Parser.isSeiMessageEia608(payloadType, payloadSize, seiBuffer)) {
-        output.sampleData(seiBuffer, payloadSize);
-        output.sampleMetadata(pesTimeUs, C.BUFFER_FLAG_KEY_FRAME, payloadSize, 0, null);
+        // Ignore country_code (1) + provider_code (2) + user_identifier (4)
+        // + user_data_type_code (1).
+        seiBuffer.skipBytes(8);
+        // Ignore first three bits: reserved (1) + process_cc_data_flag (1) + zero_bit (1).
+        int ccCount = seiBuffer.readUnsignedByte() & 0x1F;
+        seiBuffer.skipBytes(1);
+        int sampleBytes = 0;
+        for (int i = 0; i < ccCount; i++) {
+          int ccValidityAndType = seiBuffer.readUnsignedByte() & 0x07;
+          // Check that validity == 1 and type == 0.
+          if (ccValidityAndType != 0x04) {
+            seiBuffer.skipBytes(2);
+          } else {
+            sampleBytes += 2;
+            output.sampleData(seiBuffer, 2);
+          }
+        }
+        output.sampleMetadata(pesTimeUs, C.BUFFER_FLAG_KEY_FRAME, sampleBytes, 0, null);
+        // Ignore trailing information in SEI, if any.
+        seiBuffer.skipBytes(payloadSize - (10 + ccCount * 3));
       } else {
         seiBuffer.skipBytes(payloadSize);
       }

library/src/main/java/com/google/android/exoplayer2/source/smoothstreaming/SmoothStreamingChunkSource.java

@@ -90,8 +90,8 @@ public class SmoothStreamingChunkSource implements ChunkSource {
     for (int j = 0; j < formats.length; j++) {
       int nalUnitLengthFieldLength = streamElement.type == C.TRACK_TYPE_VIDEO ? 4 : -1;
       Track track = new Track(j, streamElement.type, streamElement.timescale, C.UNSET_TIME_US,
-          manifest.durationUs, formats[j], trackEncryptionBoxes, nalUnitLengthFieldLength,
-          null, null);
+          manifest.durationUs, formats[j], Track.TRANSFORMATION_NONE, trackEncryptionBoxes,
+          nalUnitLengthFieldLength, null, null);
       FragmentedMp4Extractor extractor = new FragmentedMp4Extractor(
           FragmentedMp4Extractor.FLAG_WORKAROUND_EVERY_VIDEO_FRAME_IS_SYNC_FRAME
           | FragmentedMp4Extractor.FLAG_WORKAROUND_IGNORE_TFDT_BOX, track);

library/src/main/java/com/google/android/exoplayer2/text/eia608/Eia608Parser.java

@@ -21,12 +21,10 @@ import com.google.android.exoplayer2.text.SubtitleInputBuffer;
 import com.google.android.exoplayer2.text.SubtitleOutputBuffer;
 import com.google.android.exoplayer2.text.SubtitleParser;
 import com.google.android.exoplayer2.util.Assertions;
-import com.google.android.exoplayer2.util.ParsableBitArray;
 import com.google.android.exoplayer2.util.ParsableByteArray;
 
 import android.text.TextUtils;
 
-import java.nio.ByteBuffer;
 import java.util.LinkedList;
 import java.util.TreeSet;
 
@@ -168,7 +166,7 @@ public final class Eia608Parser implements SubtitleParser {
   private final LinkedList<SubtitleOutputBuffer> availableOutputBuffers;
   private final TreeSet<SubtitleInputBuffer> queuedInputBuffers;
 
-  private final ParsableBitArray seiBuffer;
+  private final ParsableByteArray ccData;
 
   private final StringBuilder captionStringBuilder;
 
@@ -197,7 +195,7 @@ public final class Eia608Parser implements SubtitleParser {
     }
     queuedInputBuffers = new TreeSet<>();
 
-    seiBuffer = new ParsableBitArray();
+    ccData = new ParsableByteArray();
 
     captionStringBuilder = new StringBuilder();
 
@@ -310,58 +308,30 @@ public final class Eia608Parser implements SubtitleParser {
   }
 
   private void decode(SubtitleInputBuffer inputBuffer) {
-    ByteBuffer inputData = inputBuffer.data;
-    int inputSize = inputData.limit();
-    if (inputSize < 10) {
-      return;
-    }
-
-    seiBuffer.reset(inputData.array(), inputSize);
-    // country_code (8) + provider_code (16) + user_identifier (32) + user_data_type_code (8) +
-    // reserved (1) + process_cc_data_flag (1) + zero_bit (1)
-    seiBuffer.skipBits(67);
-    int ccCount = seiBuffer.readBits(5);
-    seiBuffer.skipBits(8);
-
+    ccData.reset(inputBuffer.data.array(), inputBuffer.data.limit());
     boolean captionDataProcessed = false;
     boolean isRepeatableControl = false;
-    for (int i = 0; i < ccCount; i++) {
-      seiBuffer.skipBits(5); // one_bit + reserved
-      boolean ccValid = seiBuffer.readBit();
-      if (!ccValid) {
-        seiBuffer.skipBits(18);
-        continue;
-      }
-      int ccType = seiBuffer.readBits(2);
-      if (ccType != 0) {
-        seiBuffer.skipBits(16);
-        continue;
-      }
-      seiBuffer.skipBits(1);
-      byte ccData1 = (byte) seiBuffer.readBits(7);
-      seiBuffer.skipBits(1);
-      byte ccData2 = (byte) seiBuffer.readBits(7);
+    while (ccData.bytesLeft() > 0) {
+      byte ccData1 = (byte) (ccData.readUnsignedByte() & 0x7F);
+      byte ccData2 = (byte) (ccData.readUnsignedByte() & 0x7F);
 
       // Ignore empty captions.
       if (ccData1 == 0 && ccData2 == 0) {
         continue;
       }
-
       // If we've reached this point then there is data to process; flag that work has been done.
       captionDataProcessed = true;
 
       // Special North American character set.
       // ccData2 - P|0|1|1|X|X|X|X
-      if ((ccData1 == 0x11 || ccData1 == 0x19)
-          && ((ccData2 & 0x70) == 0x30)) {
+      if ((ccData1 == 0x11 || ccData1 == 0x19) && ((ccData2 & 0x70) == 0x30)) {
         captionStringBuilder.append(getSpecialChar(ccData2));
         continue;
       }
 
       // Extended Spanish/Miscellaneous and French character set.
       // ccData2 - P|0|1|X|X|X|X|X
-      if ((ccData1 == 0x12 || ccData1 == 0x1A)
-          && ((ccData2 & 0x60) == 0x20)) {
+      if ((ccData1 == 0x12 || ccData1 == 0x1A) && ((ccData2 & 0x60) == 0x20)) {
         backspace(); // Remove standard equivalent of the special extended char.
         captionStringBuilder.append(getExtendedEsFrChar(ccData2));
         continue;
@@ -369,8 +339,7 @@ public final class Eia608Parser implements SubtitleParser {
 
       // Extended Portuguese and German/Danish character set.
       // ccData2 - P|0|1|X|X|X|X|X
-      if ((ccData1 == 0x13 || ccData1 == 0x1B)
-          && ((ccData2 & 0x60) == 0x20)) {
+      if ((ccData1 == 0x13 || ccData1 == 0x1B) && ((ccData2 & 0x60) == 0x20)) {
         backspace(); // Remove standard equivalent of the special extended char.
         captionStringBuilder.append(getExtendedPtDeChar(ccData2));
         continue;