tuner/src/com/android/tv/tuner/exoplayer/MpegTsSampleExtractor.java - platform/packages/apps/TV - Git at Google

 /*
  * Copyright (C) 2015 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.android.tv.tuner.exoplayer;

 import android.net.Uri;
 import android.os.Handler;
 import com.android.tv.tuner.exoplayer.buffer.BufferManager;
 import com.android.tv.tuner.exoplayer.buffer.PlaybackBufferListener;
 import com.android.tv.tuner.exoplayer.buffer.SamplePool;
 import com.google.android.exoplayer.MediaFormat;
 import com.google.android.exoplayer.MediaFormatHolder;
 import com.google.android.exoplayer.SampleHolder;
 import com.google.android.exoplayer.SampleSource;
 import com.google.android.exoplayer.upstream.DataSource;
 import com.google.android.exoplayer.util.MimeTypes;
 import com.android.tv.common.flags.ConcurrentDvrPlaybackFlags;
 import java.io.IOException;
 import java.nio.ByteBuffer;
 import java.util.ArrayList;
 import java.util.LinkedList;
 import java.util.List;

 /** Extracts samples from {@link DataSource} for MPEG-TS streams. */
 public final class MpegTsSampleExtractor implements SampleExtractor {
     public static final String MIMETYPE_TEXT_CEA_708 = "text/cea-708";

     private static final int CC_BUFFER_SIZE_IN_BYTES = 9600 / 8;

     private final SampleExtractor mSampleExtractor;
     private final List<MediaFormat> mTrackFormats = new ArrayList<>();
     private final List<Boolean> mReachedEos = new ArrayList<>();
     private int mVideoTrackIndex;
     private final SamplePool mCcSamplePool = new SamplePool();
     private final List<SampleHolder> mPendingCcSamples = new LinkedList<>();

     private int mCea708TextTrackIndex;
     private boolean mCea708TextTrackSelected;

     private CcParser mCcParser;

     private void init() {
         mVideoTrackIndex = -1;
         mCea708TextTrackIndex = -1;
         mCea708TextTrackSelected = false;
     }

     /**
      * Creates MpegTsSampleExtractor for {@link DataSource}.
      *
      * @param source the {@link DataSource} to extract from
      * @param bufferManager the manager for reading & writing samples backed by physical storage
      * @param bufferListener the {@link PlaybackBufferListener} to notify buffer storage status
      * @param concurrentDvrPlaybackFlags
      */
     public MpegTsSampleExtractor(
             DataSource source,
             BufferManager bufferManager,
             PlaybackBufferListener bufferListener,
             ConcurrentDvrPlaybackFlags concurrentDvrPlaybackFlags) {

         mSampleExtractor =
                 new ExoPlayerSampleExtractor(
                         Uri.EMPTY,
                         source,
                         bufferManager,
                         bufferListener,
                         false,
                         concurrentDvrPlaybackFlags);
         init();
     }

     /**
      * Creates MpegTsSampleExtractor for a recorded program.
      *
      * @param bufferManager the samples provider which is stored in physical storage
      * @param bufferListener the {@link PlaybackBufferListener} to notify buffer storage status
      *     change
      */
     public MpegTsSampleExtractor(
             BufferManager bufferManager,
             PlaybackBufferListener bufferListener,
             ConcurrentDvrPlaybackFlags concurrentDvrPlaybackFlags) {
         mSampleExtractor =
                 new FileSampleExtractor(bufferManager, bufferListener, concurrentDvrPlaybackFlags);
         init();
     }

     @Override
     public void maybeThrowError() throws IOException {
         if (mSampleExtractor != null) {
             mSampleExtractor.maybeThrowError();
         }
     }

     @Override
     public boolean prepare() throws IOException {
         if (!mSampleExtractor.prepare()) {
             return false;
         }
         List<MediaFormat> formats = mSampleExtractor.getTrackFormats();
         int trackCount = formats.size();
         mTrackFormats.clear();
         mReachedEos.clear();

         for (int i = 0; i < trackCount; ++i) {
             mTrackFormats.add(formats.get(i));
             mReachedEos.add(false);
             String mime = formats.get(i).mimeType;
             if (MimeTypes.isVideo(mime) && mVideoTrackIndex == -1) {
                 mVideoTrackIndex = i;
                 if (android.media.MediaFormat.MIMETYPE_VIDEO_MPEG2.equals(mime)) {
                     mCcParser = new Mpeg2CcParser();
                 } else if (android.media.MediaFormat.MIMETYPE_VIDEO_AVC.equals(mime)) {
                     mCcParser = new H264CcParser();
                 }
             }
         }

         if (mVideoTrackIndex != -1) {
             mCea708TextTrackIndex = trackCount;
         }
         if (mCea708TextTrackIndex >= 0) {
             mTrackFormats.add(
                     MediaFormat.createTextFormat(
                             null, MIMETYPE_TEXT_CEA_708, 0, mTrackFormats.get(0).durationUs, ""));
         }
         return true;
     }

     @Override
     public List<MediaFormat> getTrackFormats() {
         return mTrackFormats;
     }

     @Override
     public void selectTrack(int index) {
         if (index == mCea708TextTrackIndex) {
             mCea708TextTrackSelected = true;
             return;
         }
         mSampleExtractor.selectTrack(index);
     }

     @Override
     public void deselectTrack(int index) {
         if (index == mCea708TextTrackIndex) {
             mCea708TextTrackSelected = false;
             return;
         }
         mSampleExtractor.deselectTrack(index);
     }

     @Override
     public long getBufferedPositionUs() {
         return mSampleExtractor.getBufferedPositionUs();
     }

     @Override
     public void seekTo(long positionUs) {
         mSampleExtractor.seekTo(positionUs);
         for (SampleHolder holder : mPendingCcSamples) {
             mCcSamplePool.releaseSample(holder);
         }
         mPendingCcSamples.clear();
     }

     @Override
     public void getTrackMediaFormat(int track, MediaFormatHolder outMediaFormatHolder) {
         if (track != mCea708TextTrackIndex) {
             mSampleExtractor.getTrackMediaFormat(track, outMediaFormatHolder);
         }
     }

     @Override
     public int readSample(int track, SampleHolder sampleHolder) {
         if (track == mCea708TextTrackIndex) {
             if (mCea708TextTrackSelected && !mPendingCcSamples.isEmpty()) {
                 SampleHolder holder = mPendingCcSamples.remove(0);
                 holder.data.flip();
                 sampleHolder.timeUs = holder.timeUs;
                 sampleHolder.data.put(holder.data);
                 mCcSamplePool.releaseSample(holder);
                 return SampleSource.SAMPLE_READ;
             } else {
                 return mVideoTrackIndex < 0 || mReachedEos.get(mVideoTrackIndex)
                         ? SampleSource.END_OF_STREAM
                         : SampleSource.NOTHING_READ;
             }
         }

         int result = mSampleExtractor.readSample(track, sampleHolder);
         switch (result) {
             case SampleSource.END_OF_STREAM:
                 {
                     mReachedEos.set(track, true);
                     break;
                 }
             case SampleSource.SAMPLE_READ:
                 {
                     if (mCea708TextTrackSelected
                             && track == mVideoTrackIndex
                             && sampleHolder.data != null) {
                         mCcParser.mayParseClosedCaption(sampleHolder.data, sampleHolder.timeUs);
                     }
                     break;
                 }
         }
         return result;
     }

     @Override
     public void release() {
         mSampleExtractor.release();
         mVideoTrackIndex = -1;
         mCea708TextTrackIndex = -1;
         mCea708TextTrackSelected = false;
     }

     @Override
     public boolean continueBuffering(long positionUs) {
         return mSampleExtractor.continueBuffering(positionUs);
     }

     @Override
     public void setOnCompletionListener(OnCompletionListener listener, Handler handler) {}

     private abstract class CcParser {
         // Interim buffer for reduce direct access to ByteBuffer which is expensive. Using
         // relatively small buffer size in order to minimize memory footprint increase.
         protected final byte[] mBuffer = new byte[1024];

         abstract void mayParseClosedCaption(ByteBuffer buffer, long presentationTimeUs);

         protected int parseClosedCaption(ByteBuffer buffer, int offset, long presentationTimeUs) {
             // For the details of user_data_type_structure, see ATSC A/53 Part 4 - Table 6.9.
             int pos = offset;
             if (pos + 2 >= buffer.position()) {
                 return offset;
             }
             boolean processCcDataFlag = (buffer.get(pos) & 64) != 0;
             int ccCount = buffer.get(pos) & 0x1f;
             pos += 2;
             if (!processCcDataFlag || pos + 3 * ccCount >= buffer.position() || ccCount == 0) {
                 return offset;
             }
             SampleHolder holder = mCcSamplePool.acquireSample(CC_BUFFER_SIZE_IN_BYTES);
             for (int i = 0; i < 3 * ccCount; i++) {
                 holder.data.put(buffer.get(pos++));
             }
             holder.timeUs = presentationTimeUs;
             mPendingCcSamples.add(holder);
             return pos;
         }
     }

     private class Mpeg2CcParser extends CcParser {
         private static final int PATTERN_LENGTH = 9;

         @Override
         public void mayParseClosedCaption(ByteBuffer buffer, long presentationTimeUs) {
             int totalSize = buffer.position();
             // Reading the frame in bulk to reduce the overhead from ByteBuffer.get() with
             // overlapping to handle the case that the pattern exists in the boundary.
             for (int i = 0; i < totalSize; i += mBuffer.length - PATTERN_LENGTH) {
                 buffer.position(i);
                 int size = Math.min(totalSize - i, mBuffer.length);
                 buffer.get(mBuffer, 0, size);
                 int j = 0;
                 while (j < size - PATTERN_LENGTH) {
                     // Find the start prefix code of private user data.
                     if (mBuffer[j] == 0
                             && mBuffer[j + 1] == 0
                             && mBuffer[j + 2] == 1
                             && (mBuffer[j + 3] & 0xff) == 0xb2) {
                         // ATSC closed caption data embedded in MPEG2VIDEO stream has 'GA94' user
                         // identifier and user data type code 3.
                         if (mBuffer[j + 4] == 'G'
                                 && mBuffer[j + 5] == 'A'
                                 && mBuffer[j + 6] == '9'
                                 && mBuffer[j + 7] == '4'
                                 && mBuffer[j + 8] == 3) {
                             j =
                                     parseClosedCaption(
                                                     buffer,
                                                     i + j + PATTERN_LENGTH,
                                                     presentationTimeUs)
                                             - i;
                         } else {
                             j += PATTERN_LENGTH;
                         }
                     } else {
                         ++j;
                     }
                 }
             }
             buffer.position(totalSize);
         }
     }

     private class H264CcParser extends CcParser {
         private static final int PATTERN_LENGTH = 14;

         @Override
         public void mayParseClosedCaption(ByteBuffer buffer, long presentationTimeUs) {
             int totalSize = buffer.position();
             // Reading the frame in bulk to reduce the overhead from ByteBuffer.get() with
             // overlapping to handle the case that the pattern exists in the boundary.
             for (int i = 0; i < totalSize; i += mBuffer.length - PATTERN_LENGTH) {
                 buffer.position(i);
                 int size = Math.min(totalSize - i, mBuffer.length);
                 buffer.get(mBuffer, 0, size);
                 int j = 0;
                 while (j < size - PATTERN_LENGTH) {
                     // Find the start prefix code of a NAL Unit.
                     if (mBuffer[j] == 0 && mBuffer[j + 1] == 0 && mBuffer[j + 2] == 1) {
                         int nalType = mBuffer[j + 3] & 0x1f;
                         int payloadType = mBuffer[j + 4] & 0xff;

                         // ATSC closed caption data embedded in H264 private user data has NAL type
                         // 6, payload type 4, and 'GA94' user identifier for ATSC.
                         if (nalType == 6
                                 && payloadType == 4
                                 && mBuffer[j + 9] == 'G'
                                 && mBuffer[j + 10] == 'A'
                                 && mBuffer[j + 11] == '9'
                                 && mBuffer[j + 12] == '4') {
                             j =
                                     parseClosedCaption(
                                                     buffer,
                                                     i + j + PATTERN_LENGTH,
                                                     presentationTimeUs)
                                             - i;
                         } else {
                             j += 7;
                         }
                     } else {
                         ++j;
                     }
                 }
             }
             buffer.position(totalSize);
         }
     }
 }
	/*
	* Copyright (C) 2015 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.android.tv.tuner.exoplayer;

	import android.net.Uri;
	import android.os.Handler;
	import com.android.tv.tuner.exoplayer.buffer.BufferManager;
	import com.android.tv.tuner.exoplayer.buffer.PlaybackBufferListener;
	import com.android.tv.tuner.exoplayer.buffer.SamplePool;
	import com.google.android.exoplayer.MediaFormat;
	import com.google.android.exoplayer.MediaFormatHolder;
	import com.google.android.exoplayer.SampleHolder;
	import com.google.android.exoplayer.SampleSource;
	import com.google.android.exoplayer.upstream.DataSource;
	import com.google.android.exoplayer.util.MimeTypes;
	import com.android.tv.common.flags.ConcurrentDvrPlaybackFlags;
	import java.io.IOException;
	import java.nio.ByteBuffer;
	import java.util.ArrayList;
	import java.util.LinkedList;
	import java.util.List;

	/** Extracts samples from {@link DataSource} for MPEG-TS streams. */
	public final class MpegTsSampleExtractor implements SampleExtractor {
	public static final String MIMETYPE_TEXT_CEA_708 = "text/cea-708";

	private static final int CC_BUFFER_SIZE_IN_BYTES = 9600 / 8;

	private final SampleExtractor mSampleExtractor;
	private final List<MediaFormat> mTrackFormats = new ArrayList<>();
	private final List<Boolean> mReachedEos = new ArrayList<>();
	private int mVideoTrackIndex;
	private final SamplePool mCcSamplePool = new SamplePool();
	private final List<SampleHolder> mPendingCcSamples = new LinkedList<>();

	private int mCea708TextTrackIndex;
	private boolean mCea708TextTrackSelected;

	private CcParser mCcParser;

	private void init() {
	mVideoTrackIndex = -1;
	mCea708TextTrackIndex = -1;
	mCea708TextTrackSelected = false;
	}

	/**
	* Creates MpegTsSampleExtractor for {@link DataSource}.
	*
	* @param source the {@link DataSource} to extract from
	* @param bufferManager the manager for reading & writing samples backed by physical storage
	* @param bufferListener the {@link PlaybackBufferListener} to notify buffer storage status
	* @param concurrentDvrPlaybackFlags
	*/
	public MpegTsSampleExtractor(
	DataSource source,
	BufferManager bufferManager,
	PlaybackBufferListener bufferListener,
	ConcurrentDvrPlaybackFlags concurrentDvrPlaybackFlags) {

	mSampleExtractor =
	new ExoPlayerSampleExtractor(
	Uri.EMPTY,
	source,
	bufferManager,
	bufferListener,
	false,
	concurrentDvrPlaybackFlags);
	init();
	}

	/**
	* Creates MpegTsSampleExtractor for a recorded program.
	*
	* @param bufferManager the samples provider which is stored in physical storage
	* @param bufferListener the {@link PlaybackBufferListener} to notify buffer storage status
	* change
	*/
	public MpegTsSampleExtractor(
	BufferManager bufferManager,
	PlaybackBufferListener bufferListener,
	ConcurrentDvrPlaybackFlags concurrentDvrPlaybackFlags) {
	mSampleExtractor =
	new FileSampleExtractor(bufferManager, bufferListener, concurrentDvrPlaybackFlags);
	init();
	}

	@Override
	public void maybeThrowError() throws IOException {
	if (mSampleExtractor != null) {
	mSampleExtractor.maybeThrowError();
	}
	}

	@Override
	public boolean prepare() throws IOException {
	if (!mSampleExtractor.prepare()) {
	return false;
	}
	List<MediaFormat> formats = mSampleExtractor.getTrackFormats();
	int trackCount = formats.size();
	mTrackFormats.clear();
	mReachedEos.clear();

	for (int i = 0; i < trackCount; ++i) {
	mTrackFormats.add(formats.get(i));
	mReachedEos.add(false);
	String mime = formats.get(i).mimeType;
	if (MimeTypes.isVideo(mime) && mVideoTrackIndex == -1) {
	mVideoTrackIndex = i;
	if (android.media.MediaFormat.MIMETYPE_VIDEO_MPEG2.equals(mime)) {
	mCcParser = new Mpeg2CcParser();
	} else if (android.media.MediaFormat.MIMETYPE_VIDEO_AVC.equals(mime)) {
	mCcParser = new H264CcParser();
	}
	}
	}

	if (mVideoTrackIndex != -1) {
	mCea708TextTrackIndex = trackCount;
	}
	if (mCea708TextTrackIndex >= 0) {
	mTrackFormats.add(
	MediaFormat.createTextFormat(
	null, MIMETYPE_TEXT_CEA_708, 0, mTrackFormats.get(0).durationUs, ""));
	}
	return true;
	}

	@Override
	public List<MediaFormat> getTrackFormats() {
	return mTrackFormats;
	}

	@Override
	public void selectTrack(int index) {
	if (index == mCea708TextTrackIndex) {
	mCea708TextTrackSelected = true;
	return;
	}
	mSampleExtractor.selectTrack(index);
	}

	@Override
	public void deselectTrack(int index) {
	if (index == mCea708TextTrackIndex) {
	mCea708TextTrackSelected = false;
	return;
	}
	mSampleExtractor.deselectTrack(index);
	}

	@Override
	public long getBufferedPositionUs() {
	return mSampleExtractor.getBufferedPositionUs();
	}

	@Override
	public void seekTo(long positionUs) {
	mSampleExtractor.seekTo(positionUs);
	for (SampleHolder holder : mPendingCcSamples) {
	mCcSamplePool.releaseSample(holder);
	}
	mPendingCcSamples.clear();
	}

	@Override
	public void getTrackMediaFormat(int track, MediaFormatHolder outMediaFormatHolder) {
	if (track != mCea708TextTrackIndex) {
	mSampleExtractor.getTrackMediaFormat(track, outMediaFormatHolder);
	}
	}

	@Override
	public int readSample(int track, SampleHolder sampleHolder) {
	if (track == mCea708TextTrackIndex) {
	if (mCea708TextTrackSelected && !mPendingCcSamples.isEmpty()) {
	SampleHolder holder = mPendingCcSamples.remove(0);
	holder.data.flip();
	sampleHolder.timeUs = holder.timeUs;
	sampleHolder.data.put(holder.data);
	mCcSamplePool.releaseSample(holder);
	return SampleSource.SAMPLE_READ;
	} else {
	return mVideoTrackIndex < 0 \|\| mReachedEos.get(mVideoTrackIndex)
	? SampleSource.END_OF_STREAM
	: SampleSource.NOTHING_READ;
	}
	}

	int result = mSampleExtractor.readSample(track, sampleHolder);
	switch (result) {
	case SampleSource.END_OF_STREAM:
	{
	mReachedEos.set(track, true);
	break;
	}
	case SampleSource.SAMPLE_READ:
	{
	if (mCea708TextTrackSelected
	&& track == mVideoTrackIndex
	&& sampleHolder.data != null) {
	mCcParser.mayParseClosedCaption(sampleHolder.data, sampleHolder.timeUs);
	}
	break;
	}
	}
	return result;
	}

	@Override
	public void release() {
	mSampleExtractor.release();
	mVideoTrackIndex = -1;
	mCea708TextTrackIndex = -1;
	mCea708TextTrackSelected = false;
	}

	@Override
	public boolean continueBuffering(long positionUs) {
	return mSampleExtractor.continueBuffering(positionUs);
	}

	@Override
	public void setOnCompletionListener(OnCompletionListener listener, Handler handler) {}

	private abstract class CcParser {
	// Interim buffer for reduce direct access to ByteBuffer which is expensive. Using
	// relatively small buffer size in order to minimize memory footprint increase.
	protected final byte[] mBuffer = new byte[1024];

	abstract void mayParseClosedCaption(ByteBuffer buffer, long presentationTimeUs);

	protected int parseClosedCaption(ByteBuffer buffer, int offset, long presentationTimeUs) {
	// For the details of user_data_type_structure, see ATSC A/53 Part 4 - Table 6.9.
	int pos = offset;
	if (pos + 2 >= buffer.position()) {
	return offset;
	}
	boolean processCcDataFlag = (buffer.get(pos) & 64) != 0;
	int ccCount = buffer.get(pos) & 0x1f;
	pos += 2;
	if (!processCcDataFlag \|\| pos + 3 * ccCount >= buffer.position() \|\| ccCount == 0) {
	return offset;
	}
	SampleHolder holder = mCcSamplePool.acquireSample(CC_BUFFER_SIZE_IN_BYTES);
	for (int i = 0; i < 3 * ccCount; i++) {
	holder.data.put(buffer.get(pos++));
	}
	holder.timeUs = presentationTimeUs;
	mPendingCcSamples.add(holder);
	return pos;
	}
	}

	private class Mpeg2CcParser extends CcParser {
	private static final int PATTERN_LENGTH = 9;

	@Override
	public void mayParseClosedCaption(ByteBuffer buffer, long presentationTimeUs) {
	int totalSize = buffer.position();
	// Reading the frame in bulk to reduce the overhead from ByteBuffer.get() with
	// overlapping to handle the case that the pattern exists in the boundary.
	for (int i = 0; i < totalSize; i += mBuffer.length - PATTERN_LENGTH) {
	buffer.position(i);
	int size = Math.min(totalSize - i, mBuffer.length);
	buffer.get(mBuffer, 0, size);
	int j = 0;
	while (j < size - PATTERN_LENGTH) {
	// Find the start prefix code of private user data.
	if (mBuffer[j] == 0
	&& mBuffer[j + 1] == 0
	&& mBuffer[j + 2] == 1
	&& (mBuffer[j + 3] & 0xff) == 0xb2) {
	// ATSC closed caption data embedded in MPEG2VIDEO stream has 'GA94' user
	// identifier and user data type code 3.
	if (mBuffer[j + 4] == 'G'
	&& mBuffer[j + 5] == 'A'
	&& mBuffer[j + 6] == '9'
	&& mBuffer[j + 7] == '4'
	&& mBuffer[j + 8] == 3) {
	j =
	parseClosedCaption(
	buffer,
	i + j + PATTERN_LENGTH,
	presentationTimeUs)
	- i;
	} else {
	j += PATTERN_LENGTH;
	}
	} else {
	++j;
	}
	}
	}
	buffer.position(totalSize);
	}
	}

	private class H264CcParser extends CcParser {
	private static final int PATTERN_LENGTH = 14;

	@Override
	public void mayParseClosedCaption(ByteBuffer buffer, long presentationTimeUs) {
	int totalSize = buffer.position();
	// Reading the frame in bulk to reduce the overhead from ByteBuffer.get() with
	// overlapping to handle the case that the pattern exists in the boundary.
	for (int i = 0; i < totalSize; i += mBuffer.length - PATTERN_LENGTH) {
	buffer.position(i);
	int size = Math.min(totalSize - i, mBuffer.length);
	buffer.get(mBuffer, 0, size);
	int j = 0;
	while (j < size - PATTERN_LENGTH) {
	// Find the start prefix code of a NAL Unit.
	if (mBuffer[j] == 0 && mBuffer[j + 1] == 0 && mBuffer[j + 2] == 1) {
	int nalType = mBuffer[j + 3] & 0x1f;
	int payloadType = mBuffer[j + 4] & 0xff;

	// ATSC closed caption data embedded in H264 private user data has NAL type
	// 6, payload type 4, and 'GA94' user identifier for ATSC.
	if (nalType == 6
	&& payloadType == 4
	&& mBuffer[j + 9] == 'G'
	&& mBuffer[j + 10] == 'A'
	&& mBuffer[j + 11] == '9'
	&& mBuffer[j + 12] == '4') {
	j =
	parseClosedCaption(
	buffer,
	i + j + PATTERN_LENGTH,
	presentationTimeUs)
	- i;
	} else {
	j += 7;
	}
	} else {
	++j;
	}
	}
	}
	buffer.position(totalSize);
	}
	}
	}