BufferCopiedEncodedData.java
/*
* Copyright 2022 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.camera.video.internal.encoder;
import android.media.MediaCodec;
import androidx.annotation.NonNull;
import androidx.annotation.RequiresApi;
import androidx.camera.core.impl.utils.futures.Futures;
import androidx.concurrent.futures.CallbackToFutureAdapter;
import androidx.core.util.Preconditions;
import com.google.common.util.concurrent.ListenableFuture;
import java.nio.ByteBuffer;
import java.util.concurrent.atomic.AtomicReference;
/**
* A class used to hold a copy of encoded data to prevent occupying the byte buffer of the media
* codec.
*
* <p> To reduce the memory used, the capacity of the copied byte buffer may not equal to its
* source, only the required size is allocated to put the copied data.
*/
@RequiresApi(21) // TODO(b/200306659): Remove and replace with annotation on package-info.java
public class BufferCopiedEncodedData implements EncodedData {
private final ByteBuffer mByteBuffer;
private final MediaCodec.BufferInfo mBufferInfo;
private final ListenableFuture<Void> mClosedFuture;
private final CallbackToFutureAdapter.Completer<Void> mClosedCompleter;
public BufferCopiedEncodedData(@NonNull EncodedData encodedData) {
mBufferInfo = generateCopiedByteInfo(encodedData);
mByteBuffer = generateCopiedByteBuffer(encodedData);
// Prepare close future and completer
AtomicReference<CallbackToFutureAdapter.Completer<Void>> ref = new AtomicReference<>();
mClosedFuture = CallbackToFutureAdapter.getFuture(completer -> {
ref.set(completer);
return "Data closed";
});
mClosedCompleter = Preconditions.checkNotNull(ref.get());
}
@NonNull
private MediaCodec.BufferInfo generateCopiedByteInfo(@NonNull EncodedData encodedData) {
MediaCodec.BufferInfo bufferInfo = encodedData.getBufferInfo();
MediaCodec.BufferInfo copiedBufferInfo = new MediaCodec.BufferInfo();
copiedBufferInfo.set(
0,
bufferInfo.size,
bufferInfo.presentationTimeUs,
bufferInfo.flags
);
return copiedBufferInfo;
}
@NonNull
private ByteBuffer generateCopiedByteBuffer(@NonNull EncodedData encodedData) {
ByteBuffer byteBuffer = encodedData.getByteBuffer();
MediaCodec.BufferInfo bufferInfo = encodedData.getBufferInfo();
byteBuffer.position(bufferInfo.offset);
byteBuffer.limit(bufferInfo.offset + bufferInfo.size);
// Copy only the part that contents data
ByteBuffer copiedByteBuffer = ByteBuffer.allocate(bufferInfo.size);
copiedByteBuffer.order(byteBuffer.order());
copiedByteBuffer.put(byteBuffer);
copiedByteBuffer.flip();
return copiedByteBuffer;
}
/** {@inheritDoc} */
@NonNull
@Override
public ByteBuffer getByteBuffer() {
return mByteBuffer;
}
/** {@inheritDoc} */
@NonNull
@Override
public MediaCodec.BufferInfo getBufferInfo() {
return mBufferInfo;
}
/** {@inheritDoc} */
@Override
public long getPresentationTimeUs() {
return mBufferInfo.presentationTimeUs;
}
/** {@inheritDoc} */
@Override
public long size() {
return mBufferInfo.size;
}
/** {@inheritDoc} */
@Override
public boolean isKeyFrame() {
return (mBufferInfo.flags & MediaCodec.BUFFER_FLAG_KEY_FRAME) != 0;
}
/**
* No need to call this function. Resources will be released by garbage collection.
*/
@Override
public void close() {
mClosedCompleter.set(null);
}
/**
* No need to call this function. Resources will be released by garbage collection.
*/
@NonNull
@Override
public ListenableFuture<Void> getClosedFuture() {
return Futures.nonCancellationPropagating(mClosedFuture);
}
}