content: /*
   * Copyright (C) 2018 The Android Open Source Project
   *
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   *      http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  package com.google.android.exoplayer2.extractor.ts;
  
  import androidx.annotation.Nullable;
  import com.google.android.exoplayer2.C;
  import com.google.android.exoplayer2.Format;
  import com.google.android.exoplayer2.extractor.CeaUtil;
  import com.google.android.exoplayer2.extractor.ExtractorOutput;
  import com.google.android.exoplayer2.extractor.TrackOutput;
  import com.google.android.exoplayer2.util.Assertions;
  import com.google.android.exoplayer2.util.MimeTypes;
  import com.google.android.exoplayer2.util.ParsableByteArray;
  import java.util.List;
  
  /** Consumes user data, outputting contained CEA-608/708 messages to a {@link TrackOutput}. */
  /* package */ final class UserDataReader {
  
    private static final int USER_DATA_START_CODE = 0x0001B2;
  
    private final List<Format> closedCaptionFormats;
    private final TrackOutput[] outputs;
  
    public UserDataReader(List<Format> closedCaptionFormats) {
      this.closedCaptionFormats = closedCaptionFormats;
      outputs = new TrackOutput[closedCaptionFormats.size()];
    }
  
    public void createTracks(
        ExtractorOutput extractorOutput, TsPayloadReader.TrackIdGenerator idGenerator) {
      for (int i = 0; i < outputs.length; i++) {
        idGenerator.generateNewId();
        TrackOutput output = extractorOutput.track(idGenerator.getTrackId(), C.TRACK_TYPE_TEXT);
        Format channelFormat = closedCaptionFormats.get(i);
        @Nullable String channelMimeType = channelFormat.sampleMimeType;
        Assertions.checkArgument(
            MimeTypes.APPLICATION_CEA608.equals(channelMimeType)
                || MimeTypes.APPLICATION_CEA708.equals(channelMimeType),
            "Invalid closed caption mime type provided: " + channelMimeType);
        output.format(
            new Format.Builder()
                .setId(idGenerator.getFormatId())
                .setSampleMimeType(channelMimeType)
                .setSelectionFlags(channelFormat.selectionFlags)
                .setLanguage(channelFormat.language)
                .setAccessibilityChannel(channelFormat.accessibilityChannel)
                .setInitializationData(channelFormat.initializationData)
                .build());
        outputs[i] = output;
      }
    }
  
    public void consume(long pesTimeUs, ParsableByteArray userDataPayload) {
      if (userDataPayload.bytesLeft() < 9) {
        return;
      }
      int userDataStartCode = userDataPayload.readInt();
      int userDataIdentifier = userDataPayload.readInt();
      int userDataTypeCode = userDataPayload.readUnsignedByte();
      if (userDataStartCode == USER_DATA_START_CODE
          && userDataIdentifier == CeaUtil.USER_DATA_IDENTIFIER_GA94
          && userDataTypeCode == CeaUtil.USER_DATA_TYPE_CODE_MPEG_CC) {
        CeaUtil.consumeCcData(pesTimeUs, userDataPayload, outputs);
      }
    }
  }
  