使用MediaSync的Android应用在播放视频时冻结

Question

我正在尝试使用新的MediaSync API来同步播放视频和音频。 https://developer.android.com/reference/android/media/MediaSync.html

我有使用MediaSync的Audio Only播放器，但是对于Video only播放器，我在显示5-6帧后立即在logcat中得到它

I/MediaSync﹕ still waiting to release a buffer before acquire

我的视频播放器如下所示

public class VideoDecoderTask implements Runnable {
......
@Override
public void run() {

    mediaSync = new MediaSync();
    mediaSync.setSurface(surface);
    Surface inputSurface = mediaSync.createInputSurface();

    mediaExtractor = new MediaExtractor();

    try {
        mediaExtractor.setDataSource(this.clipPath);
    } catch (IOException e1) {
        e1.printStackTrace();
    }

    for (int i = 0; i < mediaExtractor.getTrackCount(); i++) {
        MediaFormat format = mediaExtractor.getTrackFormat(i);
        String mime = format.getString(MediaFormat.KEY_MIME);
        if (mime.startsWith("video/")) {
            Log.d(LOG_TAG, format.toString());
            mediaExtractor.selectTrack(i);
            try {
                videoDecoder = MediaCodec.createDecoderByType(mime);
            } catch (IOException e) {
                e.printStackTrace();
            }
            videoDecoder.configure(format, inputSurface, null, 0);
            Log.d(LOG_TAG, "Found a video track.");
            break;
        }
    }

    SyncParams syncParams = new SyncParams();
    syncParams.setSyncSource(SyncParams.SYNC_SOURCE_VSYNC);
    mediaSync.setPlaybackParams(new PlaybackParams().setSpeed(1.f));
    mediaSync.setSyncParams(syncParams);

    videoDecoder.setCallback(decoderCallback, null);
    videoDecoder.start();
}

MediaCodec.Callback decoderCallback = new MediaCodec.Callback() {
    @Override
    public void onInputBufferAvailable(MediaCodec codec, int index) {
        if (index >= 0) {
            ByteBuffer byteBuffer = codec.getInputBuffer(index);
            int sampleSize = mediaExtractor.readSampleData(byteBuffer, 0);
            Log.d(LOG_TAG, "SampleSize: " + sampleSize);
            if (sampleSize < 0) {
                //we're at end of file so submit EOS to the decoder input
                Log.d(LOG_TAG, "Video Decoder input EOS reached");
                codec.queueInputBuffer(index, 0, 0, 0, MediaCodec.BUFFER_FLAG_END_OF_STREAM);
            } else {
                long sampleTime = mediaExtractor.getSampleTime();
                codec.queueInputBuffer(index, 0, sampleSize, sampleTime, 0);
                mediaExtractor.advance();
            }
        }
    }

    @Override
    public void onOutputBufferAvailable(MediaCodec codec, int index, MediaCodec.BufferInfo info) {
        Log.d(LOG_TAG, "Rendering with preso time: " + info.presentationTimeUs);
        codec.releaseOutputBuffer(index, info.presentationTimeUs);
    }
};

}

上面的任务是从主线程开始使用的

VideoDecoderTask decoderTask = new VideoDecoderTask(clipPath, new    Surface(surface));
        Thread thread = new Thread(decoderTask);
        thread.start();

其中surface来自TextureView

我从mediasync生成的消息中得到的有根据的猜测是，由于某种原因，onOutputBufferAvailable中返回的缓冲区不会被释放回来。我需要解决这个问题？

顺便说一句，我在https://developer.android.com/preview/download.html#images的Nexus9运行开发版M上运行它

Answer 1

我发现了一个问题。

codec.releaseOutputBuffer（index，info.presentationTimeUs）;

codec.releaseOutputBuffer（index，1000 * info.presentationTimeUs）;

请参阅下面的MediaSync示例。

https://github.com/skysign/MediaSyncExample

Answer 2

如果我用SurfaceView替换输出TextureView，视频播放似乎工作正常。

虽然这解决了我的问题，但我不明白为什么使用SurfaceTexture创建的曲面和从SurfaceHolder.Per获得的曲面之间存在差异http://developer.android.com/reference/android/graphics/SurfaceTexture.html“从SurfaceTexture创建的曲面可以用作输出目标android.hardware.camera2，MediaCodec，MediaPlayer“。这几乎就是我在上面使用MediaSync / MEdiaCodec和TextureView作为输出表面的例子中所做的