usbtuner/src/com/android/usbtuner/exoplayer/MpegTsSampleSourceExtractor.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.usbtuner.exoplayer;

 import android.media.MediaDataSource;

 import com.google.android.exoplayer.MediaFormat;
 import com.google.android.exoplayer.MediaFormatHolder;
 import com.google.android.exoplayer.MediaFormatUtil;
 import com.google.android.exoplayer.SampleHolder;
 import com.google.android.exoplayer.SampleSource;
 import com.google.android.exoplayer.util.MimeTypes;
 import com.android.usbtuner.exoplayer.cache.CacheManager;
 import com.android.usbtuner.tvinput.PlaybackCacheListener;

 import java.io.IOException;
 import java.nio.ByteBuffer;

 /**
  * Extracts samples from {@link MediaDataSource} for MPEG-TS streams.
  */
 public final class MpegTsSampleSourceExtractor 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 MediaFormat[] mTrackFormats;
     private boolean[] mGotEos;
     private int mVideoTrackIndex;
     private int mCea708TextTrackIndex;
     private boolean mCea708TextTrackSelected;
     private ByteBuffer mCea708CcBuffer;

     private long mCea708PresentationTimeUs;
     private CcParser mCcParser;

     private void init() {
         mVideoTrackIndex = -1;
         mCea708TextTrackIndex = -1;
         mCea708CcBuffer = ByteBuffer.allocate(CC_BUFFER_SIZE_IN_BYTES);
         mCea708PresentationTimeUs = -1;
         mCea708TextTrackSelected = false;
     }

     /**
      * Creates MpegTsSampleSourceExtractor for {@link MediaDataSource}.
      *
      * @param source the {@link MediaDataSource} to extract from
      * @param cacheManager the manager for reading & writing samples backed by physical storage
      * @param cacheListener the {@link com.android.usbtuner.tvinput.PlaybackCacheListener}
      *                      to notify cache storage status change
      */
     public MpegTsSampleSourceExtractor(MediaDataSource source,
             CacheManager cacheManager, PlaybackCacheListener cacheListener) {
         if (cacheManager == null || cacheManager.isDisabled()) {
             mSampleExtractor =
                     new PlaySampleExtractor(source, cacheManager, cacheListener, false);

         } else {
             mSampleExtractor =
                     new PlaySampleExtractor(source, cacheManager, cacheListener, true);
         }
         init();
     }

     /**
      * Creates MpegTsSampleSourceExtractor for a recorded program.
      *
      * @param cacheManager the samples provider which is stored in physical storage
      * @param cacheListener the {@link com.android.usbtuner.tvinput.PlaybackCacheListener}
      *                      to notify cache storage status change
      */
     public MpegTsSampleSourceExtractor(CacheManager cacheManager,
             PlaybackCacheListener cacheListener) {
         mSampleExtractor = new ReplaySampleSourceExtractor(cacheManager, cacheListener);
         init();
     }

     @Override
     public boolean prepare() throws IOException {
         if(!mSampleExtractor.prepare()) {
             return false;
         }
         MediaFormat trackFormats[] = mSampleExtractor.getTrackFormats();
         int trackCount = trackFormats.length;
         mGotEos = new boolean[trackCount];

         for (int i = 0; i < trackCount; ++i) {
             String mime = trackFormats[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;
         }
         mTrackFormats = new MediaFormat[mCea708TextTrackIndex < 0 ? trackCount : trackCount + 1];
         System.arraycopy(trackFormats, 0, mTrackFormats, 0, trackCount);
         if (mCea708TextTrackIndex >= 0) {
             mTrackFormats[trackCount] = MediaFormatUtil.createTextMediaFormat(MIMETYPE_TEXT_CEA_708,
                     mTrackFormats[0].durationUs);
         }
         return true;
     }

     @Override
     public 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);
     }

     @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 && mCea708CcBuffer.position() > 0) {
                 mCea708CcBuffer.flip();
                 sampleHolder.timeUs = mCea708PresentationTimeUs;
                 sampleHolder.data.put(mCea708CcBuffer);
                 mCea708CcBuffer.clear();
                 return SampleSource.SAMPLE_READ;
             } else {
                 return mVideoTrackIndex < 0 || mGotEos[mVideoTrackIndex]
                         ? SampleSource.END_OF_STREAM : SampleSource.NOTHING_READ;
             }
         }

         // Should read CC track first.
         if (mCea708TextTrackSelected && mCea708CcBuffer.position() > 0) {
             return mGotEos[track] ? SampleSource.END_OF_STREAM : SampleSource.NOTHING_READ;
         }

         int result = mSampleExtractor.readSample(track, sampleHolder);
         switch (result) {
             case SampleSource.END_OF_STREAM: {
                 mGotEos[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);
     }

     private abstract class CcParser {
         abstract void mayParseClosedCaption(ByteBuffer buffer, long presentationTimeUs);

         protected void 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;
             }
             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;
             }
             for (int i = 0; i < 3 * ccCount; i++) {
                 mCea708CcBuffer.put(buffer.get(pos + i));
             }
             mCea708PresentationTimeUs = presentationTimeUs;
         }
     }

     private class Mpeg2CcParser extends CcParser {
         @Override
         public void mayParseClosedCaption(ByteBuffer buffer, long presentationTimeUs) {
             int pos = 0;
             while (pos + 9 < buffer.position()) {
                 // Find the start prefix code of private user data.
                 if (buffer.get(pos) == 0
                         && buffer.get(pos + 1) == 0
                         && buffer.get(pos + 2) == 1
                         && (buffer.get(pos + 3) & 0xff) == 0xb2) {
                     // ATSC closed caption data embedded in MPEG2VIDEO stream has 'GA94' user
                     // identifier and user data type code 3.
                     if (buffer.get(pos + 4) == 'G'
                             && buffer.get(pos + 5) == 'A'
                             && buffer.get(pos + 6) == '9'
                             && buffer.get(pos + 7) == '4'
                             && buffer.get(pos + 8) == 3) {
                         parseClosedCaption(buffer, pos + 9, presentationTimeUs);
                     }
                     pos += 9;
                 } else {
                     ++pos;
                 }
             }
         }
     }

     private class H264CcParser extends CcParser {
         @Override
         public void mayParseClosedCaption(ByteBuffer buffer, long presentationTimeUs) {
             int pos = 0;
             while (pos + 7 < buffer.position()) {
                 // Find the start prefix code of a NAL Unit.
                 if (buffer.get(pos) == 0
                         && buffer.get(pos + 1) == 0
                         && buffer.get(pos + 2) == 1) {
                     int nalType = buffer.get(pos + 3) & 0x1f;
                     int payloadType = buffer.get(pos + 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 && buffer.get(pos + 9) == 'G'
                             && buffer.get(pos + 10) == 'A'
                             && buffer.get(pos + 11) == '9'
                             && buffer.get(pos + 12) == '4') {
                         parseClosedCaption(buffer, pos + 14, presentationTimeUs);
                     }
                     pos += 7;
                 } else {
                     ++pos;
                 }
             }
         }
     }
 }
	/*
	* 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.usbtuner.exoplayer;

	import android.media.MediaDataSource;

	import com.google.android.exoplayer.MediaFormat;
	import com.google.android.exoplayer.MediaFormatHolder;
	import com.google.android.exoplayer.MediaFormatUtil;
	import com.google.android.exoplayer.SampleHolder;
	import com.google.android.exoplayer.SampleSource;
	import com.google.android.exoplayer.util.MimeTypes;
	import com.android.usbtuner.exoplayer.cache.CacheManager;
	import com.android.usbtuner.tvinput.PlaybackCacheListener;

	import java.io.IOException;
	import java.nio.ByteBuffer;

	/**
	* Extracts samples from {@link MediaDataSource} for MPEG-TS streams.
	*/
	public final class MpegTsSampleSourceExtractor 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 MediaFormat[] mTrackFormats;
	private boolean[] mGotEos;
	private int mVideoTrackIndex;
	private int mCea708TextTrackIndex;
	private boolean mCea708TextTrackSelected;
	private ByteBuffer mCea708CcBuffer;

	private long mCea708PresentationTimeUs;
	private CcParser mCcParser;

	private void init() {
	mVideoTrackIndex = -1;
	mCea708TextTrackIndex = -1;
	mCea708CcBuffer = ByteBuffer.allocate(CC_BUFFER_SIZE_IN_BYTES);
	mCea708PresentationTimeUs = -1;
	mCea708TextTrackSelected = false;
	}

	/**
	* Creates MpegTsSampleSourceExtractor for {@link MediaDataSource}.
	*
	* @param source the {@link MediaDataSource} to extract from
	* @param cacheManager the manager for reading & writing samples backed by physical storage
	* @param cacheListener the {@link com.android.usbtuner.tvinput.PlaybackCacheListener}
	* to notify cache storage status change
	*/
	public MpegTsSampleSourceExtractor(MediaDataSource source,
	CacheManager cacheManager, PlaybackCacheListener cacheListener) {
	if (cacheManager == null \|\| cacheManager.isDisabled()) {
	mSampleExtractor =
	new PlaySampleExtractor(source, cacheManager, cacheListener, false);

	} else {
	mSampleExtractor =
	new PlaySampleExtractor(source, cacheManager, cacheListener, true);
	}
	init();
	}

	/**
	* Creates MpegTsSampleSourceExtractor for a recorded program.
	*
	* @param cacheManager the samples provider which is stored in physical storage
	* @param cacheListener the {@link com.android.usbtuner.tvinput.PlaybackCacheListener}
	* to notify cache storage status change
	*/
	public MpegTsSampleSourceExtractor(CacheManager cacheManager,
	PlaybackCacheListener cacheListener) {
	mSampleExtractor = new ReplaySampleSourceExtractor(cacheManager, cacheListener);
	init();
	}

	@Override
	public boolean prepare() throws IOException {
	if(!mSampleExtractor.prepare()) {
	return false;
	}
	MediaFormat trackFormats[] = mSampleExtractor.getTrackFormats();
	int trackCount = trackFormats.length;
	mGotEos = new boolean[trackCount];

	for (int i = 0; i < trackCount; ++i) {
	String mime = trackFormats[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;
	}
	mTrackFormats = new MediaFormat[mCea708TextTrackIndex < 0 ? trackCount : trackCount + 1];
	System.arraycopy(trackFormats, 0, mTrackFormats, 0, trackCount);
	if (mCea708TextTrackIndex >= 0) {
	mTrackFormats[trackCount] = MediaFormatUtil.createTextMediaFormat(MIMETYPE_TEXT_CEA_708,
	mTrackFormats[0].durationUs);
	}
	return true;
	}

	@Override
	public 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);
	}

	@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 && mCea708CcBuffer.position() > 0) {
	mCea708CcBuffer.flip();
	sampleHolder.timeUs = mCea708PresentationTimeUs;
	sampleHolder.data.put(mCea708CcBuffer);
	mCea708CcBuffer.clear();
	return SampleSource.SAMPLE_READ;
	} else {
	return mVideoTrackIndex < 0 \|\| mGotEos[mVideoTrackIndex]
	? SampleSource.END_OF_STREAM : SampleSource.NOTHING_READ;
	}
	}

	// Should read CC track first.
	if (mCea708TextTrackSelected && mCea708CcBuffer.position() > 0) {
	return mGotEos[track] ? SampleSource.END_OF_STREAM : SampleSource.NOTHING_READ;
	}

	int result = mSampleExtractor.readSample(track, sampleHolder);
	switch (result) {
	case SampleSource.END_OF_STREAM: {
	mGotEos[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);
	}

	private abstract class CcParser {
	abstract void mayParseClosedCaption(ByteBuffer buffer, long presentationTimeUs);

	protected void 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;
	}
	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;
	}
	for (int i = 0; i < 3 * ccCount; i++) {
	mCea708CcBuffer.put(buffer.get(pos + i));
	}
	mCea708PresentationTimeUs = presentationTimeUs;
	}
	}

	private class Mpeg2CcParser extends CcParser {
	@Override
	public void mayParseClosedCaption(ByteBuffer buffer, long presentationTimeUs) {
	int pos = 0;
	while (pos + 9 < buffer.position()) {
	// Find the start prefix code of private user data.
	if (buffer.get(pos) == 0
	&& buffer.get(pos + 1) == 0
	&& buffer.get(pos + 2) == 1
	&& (buffer.get(pos + 3) & 0xff) == 0xb2) {
	// ATSC closed caption data embedded in MPEG2VIDEO stream has 'GA94' user
	// identifier and user data type code 3.
	if (buffer.get(pos + 4) == 'G'
	&& buffer.get(pos + 5) == 'A'
	&& buffer.get(pos + 6) == '9'
	&& buffer.get(pos + 7) == '4'
	&& buffer.get(pos + 8) == 3) {
	parseClosedCaption(buffer, pos + 9, presentationTimeUs);
	}
	pos += 9;
	} else {
	++pos;
	}
	}
	}
	}

	private class H264CcParser extends CcParser {
	@Override
	public void mayParseClosedCaption(ByteBuffer buffer, long presentationTimeUs) {
	int pos = 0;
	while (pos + 7 < buffer.position()) {
	// Find the start prefix code of a NAL Unit.
	if (buffer.get(pos) == 0
	&& buffer.get(pos + 1) == 0
	&& buffer.get(pos + 2) == 1) {
	int nalType = buffer.get(pos + 3) & 0x1f;
	int payloadType = buffer.get(pos + 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 && buffer.get(pos + 9) == 'G'
	&& buffer.get(pos + 10) == 'A'
	&& buffer.get(pos + 11) == '9'
	&& buffer.get(pos + 12) == '4') {
	parseClosedCaption(buffer, pos + 14, presentationTimeUs);
	}
	pos += 7;
	} else {
	++pos;
	}
	}
	}
	}
	}