EncodedSampleExporter.java
/*
* 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 androidx.media3.transformer;
import static androidx.media3.common.util.Assertions.checkNotNull;
import static androidx.media3.decoder.DecoderInputBuffer.BUFFER_REPLACEMENT_MODE_DIRECT;
import androidx.annotation.Nullable;
import androidx.annotation.VisibleForTesting;
import androidx.media3.common.Format;
import androidx.media3.decoder.DecoderInputBuffer;
import java.nio.ByteBuffer;
import java.nio.ByteOrder;
import java.util.Queue;
import java.util.concurrent.ConcurrentLinkedQueue;
import java.util.concurrent.atomic.AtomicLong;
/** Muxes encoded samples without any transcoding or transformation. */
/* package */ final class EncodedSampleExporter extends SampleExporter implements GraphInput {
// These constants limit the number of buffers used to pass input data. More buffers can avoid the
// producer/consumer having to wait, but can increase allocation size (determined by the producer
// side) so we constrain the number of buffers to be in this range, and prevent allocating more
// buffers (above the minimum number) once a target size has been reached. Once the target has
// been reached, no new buffers will be created but the producer can still increase the size of
// existing buffers.
@VisibleForTesting /* package */ static final int MIN_INPUT_BUFFER_COUNT = 10;
@VisibleForTesting /* package */ static final int MAX_INPUT_BUFFER_COUNT = 200;
@VisibleForTesting /* package */ static final long ALLOCATION_SIZE_TARGET_BYTES = 2 * 1024 * 1024;
/** An empty, direct {@link ByteBuffer}. */
private static final ByteBuffer EMPTY_BUFFER =
ByteBuffer.allocateDirect(0).order(ByteOrder.nativeOrder());
private final Format format;
private final long initialTimestampOffsetUs;
private final AtomicLong nextMediaItemOffsetUs;
private final Queue<DecoderInputBuffer> availableInputBuffers;
private final Queue<DecoderInputBuffer> pendingInputBuffers;
// Accessed on the producer and consumer threads.
private volatile boolean inputEnded;
// Accessed only on the producer thread.
private long mediaItemOffsetUs;
private boolean hasReachedAllocationTarget;
private long totalBufferSizeBytes;
@Nullable private DecoderInputBuffer nextInputBuffer;
public EncodedSampleExporter(
Format format,
TransformationRequest transformationRequest,
MuxerWrapper muxerWrapper,
FallbackListener fallbackListener,
long initialTimestampOffsetUs) {
super(format, muxerWrapper);
this.format = format;
this.initialTimestampOffsetUs = initialTimestampOffsetUs;
nextMediaItemOffsetUs = new AtomicLong();
availableInputBuffers = new ConcurrentLinkedQueue<>();
pendingInputBuffers = new ConcurrentLinkedQueue<>();
fallbackListener.onTransformationRequestFinalized(transformationRequest);
}
@Override
public void onMediaItemChanged(
EditedMediaItem editedMediaItem,
long durationUs,
@Nullable Format trackFormat,
boolean isLast) {
mediaItemOffsetUs = nextMediaItemOffsetUs.get();
nextMediaItemOffsetUs.addAndGet(durationUs);
}
@Override
@Nullable
public DecoderInputBuffer getInputBuffer() {
if (nextInputBuffer == null) {
nextInputBuffer = availableInputBuffers.poll();
if (!hasReachedAllocationTarget) {
if (nextInputBuffer == null) {
nextInputBuffer = new DecoderInputBuffer(BUFFER_REPLACEMENT_MODE_DIRECT);
nextInputBuffer.data = EMPTY_BUFFER;
} else {
// The size of this buffer has already been accounted for but the producer may reallocate
// it so remove it from the total and add it back when it's queued again.
totalBufferSizeBytes -= checkNotNull(nextInputBuffer.data).capacity();
}
}
}
return nextInputBuffer;
}
@Override
public boolean queueInputBuffer() {
DecoderInputBuffer inputBuffer = checkNotNull(nextInputBuffer);
nextInputBuffer = null;
if (inputBuffer.isEndOfStream()) {
inputEnded = true;
} else {
inputBuffer.timeUs += mediaItemOffsetUs + initialTimestampOffsetUs;
pendingInputBuffers.add(inputBuffer);
}
if (!hasReachedAllocationTarget) {
int bufferCount = availableInputBuffers.size() + pendingInputBuffers.size();
totalBufferSizeBytes += checkNotNull(inputBuffer.data).capacity();
hasReachedAllocationTarget =
bufferCount >= MIN_INPUT_BUFFER_COUNT
&& (bufferCount >= MAX_INPUT_BUFFER_COUNT
|| totalBufferSizeBytes >= ALLOCATION_SIZE_TARGET_BYTES);
}
return true;
}
@Override
public GraphInput getInput(EditedMediaItem item, Format format) {
return this;
}
@Override
public void release() {}
@Override
protected Format getMuxerInputFormat() {
return format;
}
@Override
@Nullable
protected DecoderInputBuffer getMuxerInputBuffer() {
return pendingInputBuffers.peek();
}
@Override
protected void releaseMuxerInputBuffer() {
DecoderInputBuffer inputBuffer = pendingInputBuffers.remove();
inputBuffer.clear();
inputBuffer.timeUs = 0;
availableInputBuffers.add(inputBuffer);
}
@Override
protected boolean isMuxerInputEnded() {
return inputEnded && pendingInputBuffers.isEmpty();
}
}