content: /*
   * Copyright (C) 2016 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.video;
  
  import com.google.android.exoplayer2.ParserException;
  import com.google.android.exoplayer2.util.NalUnitUtil;
  import com.google.android.exoplayer2.util.ParsableByteArray;
  import java.util.Collections;
  import java.util.List;
  
  /**
   * HEVC configuration data.
   */
  public final class HevcConfig {
  
    public final List<byte[]> initializationData;
    public final int nalUnitLengthFieldLength;
  
    /**
     * Parses HEVC configuration data.
     *
     * @param data A {@link ParsableByteArray}, whose position is set to the start of the HEVC
     *     configuration data to parse.
     * @return A parsed representation of the HEVC configuration data.
     * @throws ParserException If an error occurred parsing the data.
     */
    public static HevcConfig parse(ParsableByteArray data) throws ParserException {
      try {
        data.skipBytes(21); // Skip to the NAL unit length size field.
        int lengthSizeMinusOne = data.readUnsignedByte() & 0x03;
  
        // Calculate the combined size of all VPS/SPS/PPS bitstreams.
        int numberOfArrays = data.readUnsignedByte();
        int csdLength = 0;
        int csdStartPosition = data.getPosition();
        for (int i = 0; i < numberOfArrays; i++) {
          data.skipBytes(1); // completeness (1), nal_unit_type (7)
          int numberOfNalUnits = data.readUnsignedShort();
          for (int j = 0; j < numberOfNalUnits; j++) {
            int nalUnitLength = data.readUnsignedShort();
            csdLength += 4 + nalUnitLength; // Start code and NAL unit.
            data.skipBytes(nalUnitLength);
          }
        }
  
        // Concatenate the codec-specific data into a single buffer.
        data.setPosition(csdStartPosition);
        byte[] buffer = new byte[csdLength];
        int bufferPosition = 0;
        for (int i = 0; i < numberOfArrays; i++) {
          data.skipBytes(1); // completeness (1), nal_unit_type (7)
          int numberOfNalUnits = data.readUnsignedShort();
          for (int j = 0; j < numberOfNalUnits; j++) {
            int nalUnitLength = data.readUnsignedShort();
            System.arraycopy(NalUnitUtil.NAL_START_CODE, 0, buffer, bufferPosition,
                NalUnitUtil.NAL_START_CODE.length);
            bufferPosition += NalUnitUtil.NAL_START_CODE.length;
            System
                .arraycopy(data.data, data.getPosition(), buffer, bufferPosition, nalUnitLength);
            bufferPosition += nalUnitLength;
            data.skipBytes(nalUnitLength);
          }
        }
  
        List<byte[]> initializationData = csdLength == 0 ? null : Collections.singletonList(buffer);
        return new HevcConfig(initializationData, lengthSizeMinusOne + 1);
      } catch (ArrayIndexOutOfBoundsException e) {
        throw new ParserException("Error parsing HEVC config", e);
      }
    }
  
    private HevcConfig(List<byte[]> initializationData, int nalUnitLengthFieldLength) {
      this.initializationData = initializationData;
      this.nalUnitLengthFieldLength = nalUnitLengthFieldLength;
    }
  
  }
  