android-34/com/google/android/exoplayer2/text/SubtitleExtractor.java - platform/prebuilts/fullsdk/sources - Git at Google

 /*
  * Copyright 2021 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.text;

 import static com.google.android.exoplayer2.util.Assertions.checkState;
 import static com.google.android.exoplayer2.util.Assertions.checkStateNotNull;

 import androidx.annotation.IntDef;
 import androidx.annotation.Nullable;
 import com.google.android.exoplayer2.C;
 import com.google.android.exoplayer2.Format;
 import com.google.android.exoplayer2.ParserException;
 import com.google.android.exoplayer2.extractor.Extractor;
 import com.google.android.exoplayer2.extractor.ExtractorInput;
 import com.google.android.exoplayer2.extractor.ExtractorOutput;
 import com.google.android.exoplayer2.extractor.IndexSeekMap;
 import com.google.android.exoplayer2.extractor.PositionHolder;
 import com.google.android.exoplayer2.extractor.TrackOutput;
 import com.google.android.exoplayer2.util.MimeTypes;
 import com.google.android.exoplayer2.util.ParsableByteArray;
 import com.google.android.exoplayer2.util.Util;
 import com.google.common.primitives.Ints;
 import java.io.IOException;
 import java.io.InterruptedIOException;
 import java.lang.annotation.Retention;
 import java.lang.annotation.RetentionPolicy;
 import java.util.ArrayList;
 import java.util.List;
 import org.checkerframework.checker.nullness.qual.MonotonicNonNull;

 /** Generic extractor for extracting subtitles from various subtitle formats. */
 public class SubtitleExtractor implements Extractor {
   @Retention(RetentionPolicy.SOURCE)
   @IntDef({
     STATE_CREATED,
     STATE_INITIALIZED,
     STATE_EXTRACTING,
     STATE_SEEKING,
     STATE_FINISHED,
     STATE_RELEASED
   })
   private @interface State {}

   /** The extractor has been created. */
   private static final int STATE_CREATED = 0;
   /** The extractor has been initialized. */
   private static final int STATE_INITIALIZED = 1;
   /** The extractor is reading from the input and writing to the output. */
   private static final int STATE_EXTRACTING = 2;
   /** The extractor has received a seek() operation after it has already finished extracting. */
   private static final int STATE_SEEKING = 3;
   /** The extractor has finished extracting the input. */
   private static final int STATE_FINISHED = 4;
   /** The extractor has been released. */
   private static final int STATE_RELEASED = 5;

   private static final int DEFAULT_BUFFER_SIZE = 1024;

   private final SubtitleDecoder subtitleDecoder;
   private final CueEncoder cueEncoder;
   private final ParsableByteArray subtitleData;
   private final Format format;
   private final List<Long> timestamps;
   private final List<ParsableByteArray> samples;

   private @MonotonicNonNull ExtractorOutput extractorOutput;
   private @MonotonicNonNull TrackOutput trackOutput;
   private int bytesRead;
   @State private int state;
   private long seekTimeUs;

   /**
    * @param subtitleDecoder The decoder used for decoding the subtitle data. The extractor will
    *     release the decoder in {@link SubtitleExtractor#release()}.
    * @param format Format that describes subtitle data.
    */
   public SubtitleExtractor(SubtitleDecoder subtitleDecoder, Format format) {
     this.subtitleDecoder = subtitleDecoder;
     cueEncoder = new CueEncoder();
     subtitleData = new ParsableByteArray();
     this.format =
         format
             .buildUpon()
             .setSampleMimeType(MimeTypes.TEXT_EXOPLAYER_CUES)
             .setCodecs(format.sampleMimeType)
             .build();
     timestamps = new ArrayList<>();
     samples = new ArrayList<>();
     state = STATE_CREATED;
     seekTimeUs = C.TIME_UNSET;
   }

   @Override
   public boolean sniff(ExtractorInput input) throws IOException {
     // TODO: Implement sniff() according to the Extractor interface documentation. For now sniff()
     // can safely return true because we plan to use this class in an ExtractorFactory that returns
     // exactly one Extractor implementation.
     return true;
   }

   @Override
   public void init(ExtractorOutput output) {
     checkState(state == STATE_CREATED);
     extractorOutput = output;
     trackOutput = extractorOutput.track(/* id= */ 0, C.TRACK_TYPE_TEXT);
     extractorOutput.endTracks();
     extractorOutput.seekMap(
         new IndexSeekMap(
             /* positions= */ new long[] {0},
             /* timesUs= */ new long[] {0},
             /* durationUs= */ C.TIME_UNSET));
     trackOutput.format(format);
     state = STATE_INITIALIZED;
   }

   @Override
   public int read(ExtractorInput input, PositionHolder seekPosition) throws IOException {
     checkState(state != STATE_CREATED && state != STATE_RELEASED);
     if (state == STATE_INITIALIZED) {
       subtitleData.reset(
           input.getLength() != C.LENGTH_UNSET
               ? Ints.checkedCast(input.getLength())
               : DEFAULT_BUFFER_SIZE);
       bytesRead = 0;
       state = STATE_EXTRACTING;
     }
     if (state == STATE_EXTRACTING) {
       boolean inputFinished = readFromInput(input);
       if (inputFinished) {
         decode();
         writeToOutput();
         state = STATE_FINISHED;
       }
     }
     if (state == STATE_SEEKING) {
       boolean inputFinished = skipInput(input);
       if (inputFinished) {
         writeToOutput();
         state = STATE_FINISHED;
       }
     }
     if (state == STATE_FINISHED) {
       return RESULT_END_OF_INPUT;
     }
     return RESULT_CONTINUE;
   }

   @Override
   public void seek(long position, long timeUs) {
     checkState(state != STATE_CREATED && state != STATE_RELEASED);
     seekTimeUs = timeUs;
     if (state == STATE_EXTRACTING) {
       state = STATE_INITIALIZED;
     }
     if (state == STATE_FINISHED) {
       state = STATE_SEEKING;
     }
   }

   /** Releases the extractor's resources, including the {@link SubtitleDecoder}. */
   @Override
   public void release() {
     if (state == STATE_RELEASED) {
       return;
     }
     subtitleDecoder.release();
     state = STATE_RELEASED;
   }

   /** Returns whether the input has been fully skipped. */
   private boolean skipInput(ExtractorInput input) throws IOException {
     return input.skip(
             input.getLength() != C.LENGTH_UNSET
                 ? Ints.checkedCast(input.getLength())
                 : DEFAULT_BUFFER_SIZE)
         == C.RESULT_END_OF_INPUT;
   }

   /** Returns whether reading has been finished. */
   private boolean readFromInput(ExtractorInput input) throws IOException {
     if (subtitleData.capacity() == bytesRead) {
       subtitleData.ensureCapacity(bytesRead + DEFAULT_BUFFER_SIZE);
     }
     int readResult =
         input.read(subtitleData.getData(), bytesRead, subtitleData.capacity() - bytesRead);
     if (readResult != C.RESULT_END_OF_INPUT) {
       bytesRead += readResult;
     }
     long inputLength = input.getLength();
     return (inputLength != C.LENGTH_UNSET && bytesRead == inputLength)
         || readResult == C.RESULT_END_OF_INPUT;
   }

   /** Decodes the subtitle data and stores the samples in the memory of the extractor. */
   private void decode() throws IOException {
     try {
       @Nullable SubtitleInputBuffer inputBuffer = subtitleDecoder.dequeueInputBuffer();
       while (inputBuffer == null) {
         Thread.sleep(5);
         inputBuffer = subtitleDecoder.dequeueInputBuffer();
       }
       inputBuffer.ensureSpaceForWrite(bytesRead);
       inputBuffer.data.put(subtitleData.getData(), /* offset= */ 0, bytesRead);
       inputBuffer.data.limit(bytesRead);
       subtitleDecoder.queueInputBuffer(inputBuffer);
       @Nullable SubtitleOutputBuffer outputBuffer = subtitleDecoder.dequeueOutputBuffer();
       while (outputBuffer == null) {
         Thread.sleep(5);
         outputBuffer = subtitleDecoder.dequeueOutputBuffer();
       }
       for (int i = 0; i < outputBuffer.getEventTimeCount(); i++) {
         List<Cue> cues = outputBuffer.getCues(outputBuffer.getEventTime(i));
         byte[] cuesSample = cueEncoder.encode(cues);
         timestamps.add(outputBuffer.getEventTime(i));
         samples.add(new ParsableByteArray(cuesSample));
       }
       outputBuffer.release();
     } catch (InterruptedException e) {
       Thread.currentThread().interrupt();
       throw new InterruptedIOException();
     } catch (SubtitleDecoderException e) {
       throw ParserException.createForMalformedContainer("SubtitleDecoder failed.", e);
     }
   }

   private void writeToOutput() {
     checkStateNotNull(this.trackOutput);
     checkState(timestamps.size() == samples.size());
     int index =
         seekTimeUs == C.TIME_UNSET
             ? 0
             : Util.binarySearchFloor(
                 timestamps, seekTimeUs, /* inclusive= */ true, /* stayInBounds= */ true);
     for (int i = index; i < samples.size(); i++) {
       ParsableByteArray sample = samples.get(i);
       sample.setPosition(0);
       int size = sample.getData().length;
       trackOutput.sampleData(sample, size);
       trackOutput.sampleMetadata(
           /* timeUs= */ timestamps.get(i),
           /* flags= */ C.BUFFER_FLAG_KEY_FRAME,
           /* size= */ size,
           /* offset= */ 0,
           /* cryptoData= */ null);
     }
   }
 }
	/*
	* Copyright 2021 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.text;

	import static com.google.android.exoplayer2.util.Assertions.checkState;
	import static com.google.android.exoplayer2.util.Assertions.checkStateNotNull;

	import androidx.annotation.IntDef;
	import androidx.annotation.Nullable;
	import com.google.android.exoplayer2.C;
	import com.google.android.exoplayer2.Format;
	import com.google.android.exoplayer2.ParserException;
	import com.google.android.exoplayer2.extractor.Extractor;
	import com.google.android.exoplayer2.extractor.ExtractorInput;
	import com.google.android.exoplayer2.extractor.ExtractorOutput;
	import com.google.android.exoplayer2.extractor.IndexSeekMap;
	import com.google.android.exoplayer2.extractor.PositionHolder;
	import com.google.android.exoplayer2.extractor.TrackOutput;
	import com.google.android.exoplayer2.util.MimeTypes;
	import com.google.android.exoplayer2.util.ParsableByteArray;
	import com.google.android.exoplayer2.util.Util;
	import com.google.common.primitives.Ints;
	import java.io.IOException;
	import java.io.InterruptedIOException;
	import java.lang.annotation.Retention;
	import java.lang.annotation.RetentionPolicy;
	import java.util.ArrayList;
	import java.util.List;
	import org.checkerframework.checker.nullness.qual.MonotonicNonNull;

	/** Generic extractor for extracting subtitles from various subtitle formats. */
	public class SubtitleExtractor implements Extractor {
	@Retention(RetentionPolicy.SOURCE)
	@IntDef({
	STATE_CREATED,
	STATE_INITIALIZED,
	STATE_EXTRACTING,
	STATE_SEEKING,
	STATE_FINISHED,
	STATE_RELEASED
	})
	private @interface State {}

	/** The extractor has been created. */
	private static final int STATE_CREATED = 0;
	/** The extractor has been initialized. */
	private static final int STATE_INITIALIZED = 1;
	/** The extractor is reading from the input and writing to the output. */
	private static final int STATE_EXTRACTING = 2;
	/** The extractor has received a seek() operation after it has already finished extracting. */
	private static final int STATE_SEEKING = 3;
	/** The extractor has finished extracting the input. */
	private static final int STATE_FINISHED = 4;
	/** The extractor has been released. */
	private static final int STATE_RELEASED = 5;

	private static final int DEFAULT_BUFFER_SIZE = 1024;

	private final SubtitleDecoder subtitleDecoder;
	private final CueEncoder cueEncoder;
	private final ParsableByteArray subtitleData;
	private final Format format;
	private final List<Long> timestamps;
	private final List<ParsableByteArray> samples;

	private @MonotonicNonNull ExtractorOutput extractorOutput;
	private @MonotonicNonNull TrackOutput trackOutput;
	private int bytesRead;
	@State private int state;
	private long seekTimeUs;

	/**
	* @param subtitleDecoder The decoder used for decoding the subtitle data. The extractor will
	* release the decoder in {@link SubtitleExtractor#release()}.
	* @param format Format that describes subtitle data.
	*/
	public SubtitleExtractor(SubtitleDecoder subtitleDecoder, Format format) {
	this.subtitleDecoder = subtitleDecoder;
	cueEncoder = new CueEncoder();
	subtitleData = new ParsableByteArray();
	this.format =
	format
	.buildUpon()
	.setSampleMimeType(MimeTypes.TEXT_EXOPLAYER_CUES)
	.setCodecs(format.sampleMimeType)
	.build();
	timestamps = new ArrayList<>();
	samples = new ArrayList<>();
	state = STATE_CREATED;
	seekTimeUs = C.TIME_UNSET;
	}

	@Override
	public boolean sniff(ExtractorInput input) throws IOException {
	// TODO: Implement sniff() according to the Extractor interface documentation. For now sniff()
	// can safely return true because we plan to use this class in an ExtractorFactory that returns
	// exactly one Extractor implementation.
	return true;
	}

	@Override
	public void init(ExtractorOutput output) {
	checkState(state == STATE_CREATED);
	extractorOutput = output;
	trackOutput = extractorOutput.track(/* id= */ 0, C.TRACK_TYPE_TEXT);
	extractorOutput.endTracks();
	extractorOutput.seekMap(
	new IndexSeekMap(
	/* positions= */ new long[] {0},
	/* timesUs= */ new long[] {0},
	/* durationUs= */ C.TIME_UNSET));
	trackOutput.format(format);
	state = STATE_INITIALIZED;
	}

	@Override
	public int read(ExtractorInput input, PositionHolder seekPosition) throws IOException {
	checkState(state != STATE_CREATED && state != STATE_RELEASED);
	if (state == STATE_INITIALIZED) {
	subtitleData.reset(
	input.getLength() != C.LENGTH_UNSET
	? Ints.checkedCast(input.getLength())
	: DEFAULT_BUFFER_SIZE);
	bytesRead = 0;
	state = STATE_EXTRACTING;
	}
	if (state == STATE_EXTRACTING) {
	boolean inputFinished = readFromInput(input);
	if (inputFinished) {
	decode();
	writeToOutput();
	state = STATE_FINISHED;
	}
	}
	if (state == STATE_SEEKING) {
	boolean inputFinished = skipInput(input);
	if (inputFinished) {
	writeToOutput();
	state = STATE_FINISHED;
	}
	}
	if (state == STATE_FINISHED) {
	return RESULT_END_OF_INPUT;
	}
	return RESULT_CONTINUE;
	}

	@Override
	public void seek(long position, long timeUs) {
	checkState(state != STATE_CREATED && state != STATE_RELEASED);
	seekTimeUs = timeUs;
	if (state == STATE_EXTRACTING) {
	state = STATE_INITIALIZED;
	}
	if (state == STATE_FINISHED) {
	state = STATE_SEEKING;
	}
	}

	/** Releases the extractor's resources, including the {@link SubtitleDecoder}. */
	@Override
	public void release() {
	if (state == STATE_RELEASED) {
	return;
	}
	subtitleDecoder.release();
	state = STATE_RELEASED;
	}

	/** Returns whether the input has been fully skipped. */
	private boolean skipInput(ExtractorInput input) throws IOException {
	return input.skip(
	input.getLength() != C.LENGTH_UNSET
	? Ints.checkedCast(input.getLength())
	: DEFAULT_BUFFER_SIZE)
	== C.RESULT_END_OF_INPUT;
	}

	/** Returns whether reading has been finished. */
	private boolean readFromInput(ExtractorInput input) throws IOException {
	if (subtitleData.capacity() == bytesRead) {
	subtitleData.ensureCapacity(bytesRead + DEFAULT_BUFFER_SIZE);
	}
	int readResult =
	input.read(subtitleData.getData(), bytesRead, subtitleData.capacity() - bytesRead);
	if (readResult != C.RESULT_END_OF_INPUT) {
	bytesRead += readResult;
	}
	long inputLength = input.getLength();
	return (inputLength != C.LENGTH_UNSET && bytesRead == inputLength)
	\|\| readResult == C.RESULT_END_OF_INPUT;
	}

	/** Decodes the subtitle data and stores the samples in the memory of the extractor. */
	private void decode() throws IOException {
	try {
	@Nullable SubtitleInputBuffer inputBuffer = subtitleDecoder.dequeueInputBuffer();
	while (inputBuffer == null) {
	Thread.sleep(5);
	inputBuffer = subtitleDecoder.dequeueInputBuffer();
	}
	inputBuffer.ensureSpaceForWrite(bytesRead);
	inputBuffer.data.put(subtitleData.getData(), /* offset= */ 0, bytesRead);
	inputBuffer.data.limit(bytesRead);
	subtitleDecoder.queueInputBuffer(inputBuffer);
	@Nullable SubtitleOutputBuffer outputBuffer = subtitleDecoder.dequeueOutputBuffer();
	while (outputBuffer == null) {
	Thread.sleep(5);
	outputBuffer = subtitleDecoder.dequeueOutputBuffer();
	}
	for (int i = 0; i < outputBuffer.getEventTimeCount(); i++) {
	List<Cue> cues = outputBuffer.getCues(outputBuffer.getEventTime(i));
	byte[] cuesSample = cueEncoder.encode(cues);
	timestamps.add(outputBuffer.getEventTime(i));
	samples.add(new ParsableByteArray(cuesSample));
	}
	outputBuffer.release();
	} catch (InterruptedException e) {
	Thread.currentThread().interrupt();
	throw new InterruptedIOException();
	} catch (SubtitleDecoderException e) {
	throw ParserException.createForMalformedContainer("SubtitleDecoder failed.", e);
	}
	}

	private void writeToOutput() {
	checkStateNotNull(this.trackOutput);
	checkState(timestamps.size() == samples.size());
	int index =
	seekTimeUs == C.TIME_UNSET
	? 0
	: Util.binarySearchFloor(
	timestamps, seekTimeUs, /* inclusive= / true, / stayInBounds= */ true);
	for (int i = index; i < samples.size(); i++) {
	ParsableByteArray sample = samples.get(i);
	sample.setPosition(0);
	int size = sample.getData().length;
	trackOutput.sampleData(sample, size);
	trackOutput.sampleMetadata(
	/* timeUs= */ timestamps.get(i),
	/* flags= */ C.BUFFER_FLAG_KEY_FRAME,
	/* size= */ size,
	/* offset= */ 0,
	/* cryptoData= */ null);
	}
	}
	}