android.media.MediaExtractor#SAMPLE_FLAG_ENCRYPTED源码实例Demo

@SuppressLint("InlinedApi")
private void readSampleEncryptionData(ParsableByteArray sampleEncryptionData, SampleHolder out) {
  TrackEncryptionBox encryptionBox =
      track.sampleDescriptionEncryptionBoxes[fragmentRun.sampleDescriptionIndex];
  byte[] keyId = encryptionBox.keyId;
  boolean isEncrypted = encryptionBox.isEncrypted;
  int vectorSize = encryptionBox.initializationVectorSize;
  boolean subsampleEncryption = fragmentRun.sampleHasSubsampleEncryptionTable[sampleIndex];

  byte[] vector = out.cryptoInfo.iv;
  if (vector == null || vector.length != 16) {
    vector = new byte[16];
  }
  sampleEncryptionData.readBytes(vector, 0, vectorSize);

  int subsampleCount = subsampleEncryption ? sampleEncryptionData.readUnsignedShort() : 1;
  int[] clearDataSizes = out.cryptoInfo.numBytesOfClearData;
  if (clearDataSizes == null || clearDataSizes.length < subsampleCount) {
    clearDataSizes = new int[subsampleCount];
  }
  int[] encryptedDataSizes = out.cryptoInfo.numBytesOfEncryptedData;
  if (encryptedDataSizes == null || encryptedDataSizes.length < subsampleCount) {
    encryptedDataSizes = new int[subsampleCount];
  }
  if (subsampleEncryption) {
    for (int i = 0; i < subsampleCount; i++) {
      clearDataSizes[i] = sampleEncryptionData.readUnsignedShort();
      encryptedDataSizes[i] = sampleEncryptionData.readUnsignedIntToInt();
    }
  } else {
    clearDataSizes[0] = 0;
    encryptedDataSizes[0] = fragmentRun.sampleSizeTable[sampleIndex];
  }
  out.cryptoInfo.set(subsampleCount, clearDataSizes, encryptedDataSizes, keyId, vector,
      isEncrypted ? MediaCodec.CRYPTO_MODE_AES_CTR : MediaCodec.CRYPTO_MODE_UNENCRYPTED);
  if (isEncrypted) {
    out.flags |= MediaExtractor.SAMPLE_FLAG_ENCRYPTED;
  }
}
 

@Override
  public int readSample(int track, SampleHolder sampleHolder) {
    int sampleTrack = mediaExtractor.getSampleTrackIndex();
    if (sampleTrack != track) {
      return sampleTrack < 0 ? SampleSource.END_OF_STREAM : SampleSource.NOTHING_READ;
    }

    if (sampleHolder.data != null) {
      int offset = sampleHolder.data.position();
      sampleHolder.size = mediaExtractor.readSampleData(sampleHolder.data, offset);
      sampleHolder.data.position(offset + sampleHolder.size);
    } else {
      sampleHolder.size = 0;
    }
    sampleHolder.timeUs = mediaExtractor.getSampleTime();
    sampleHolder.flags = mediaExtractor.getSampleFlags();
    if ((sampleHolder.flags & MediaExtractor.SAMPLE_FLAG_ENCRYPTED) != 0) {
      sampleHolder.cryptoInfo.setFromExtractorV16(mediaExtractor);
    }

//      // yy debug stuff
//      if (MediaCodecVideoTrackRenderer.bb == null) {
//          MediaCodecVideoTrackRenderer.bb = new ArrayList<byte[]>();
//      }
//      int len = sampleHolder.size;
//      byte[] dd = new byte[len];
//      for (int i=0; i<len; i++) {
//          dd[i] = sampleHolder.data.get(i);
//      }
//      MediaCodecVideoTrackRenderer.bb.add(dd);
//
//      if (MediaCodecVideoTrackRenderer.pts == null) {
//          MediaCodecVideoTrackRenderer.pts = new ArrayList<Long>();
//      }
//      MediaCodecVideoTrackRenderer.pts.add(new Long(sampleHolder.timeUs));

      mediaExtractor.advance();

    return SampleSource.SAMPLE_READ;
  }