SubtitleOutputBuffer.java
/*
* 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 androidx.media3.extractor.text;
import androidx.annotation.Nullable;
import androidx.media3.common.Format;
import androidx.media3.common.text.Cue;
import androidx.media3.common.util.Assertions;
import androidx.media3.common.util.UnstableApi;
import androidx.media3.decoder.DecoderOutputBuffer;
import java.util.List;
/** Base class for {@link SubtitleDecoder} output buffers. */
@UnstableApi
public abstract class SubtitleOutputBuffer extends DecoderOutputBuffer implements Subtitle {
@Nullable private Subtitle subtitle;
private long subsampleOffsetUs;
/**
* Sets the content of the output buffer, consisting of a {@link Subtitle} and associated
* metadata.
*
* @param timeUs The time of the start of the subtitle in microseconds.
* @param subtitle The subtitle.
* @param subsampleOffsetUs An offset that must be added to the subtitle's event times, or {@link
* Format#OFFSET_SAMPLE_RELATIVE} if {@code timeUs} should be added.
*/
public void setContent(long timeUs, Subtitle subtitle, long subsampleOffsetUs) {
this.timeUs = timeUs;
this.subtitle = subtitle;
this.subsampleOffsetUs =
subsampleOffsetUs == Format.OFFSET_SAMPLE_RELATIVE ? this.timeUs : subsampleOffsetUs;
}
@Override
public int getEventTimeCount() {
return Assertions.checkNotNull(subtitle).getEventTimeCount();
}
@Override
public long getEventTime(int index) {
return Assertions.checkNotNull(subtitle).getEventTime(index) + subsampleOffsetUs;
}
@Override
public int getNextEventTimeIndex(long timeUs) {
return Assertions.checkNotNull(subtitle).getNextEventTimeIndex(timeUs - subsampleOffsetUs);
}
@Override
public List<Cue> getCues(long timeUs) {
return Assertions.checkNotNull(subtitle).getCues(timeUs - subsampleOffsetUs);
}
@Override
public void clear() {
super.clear();
subtitle = null;
}
}