问如何在Java环境下解码H.264视频帧

EN

public class StreamingClient extends Application implements GrabberListener
{
    public static void main(String[] args)
    {
        launch(args);
    }

    private Stage primaryStage;
    private ImageView imageView;

    private SimplePlayer simplePlayer;

    @Override
    public void start(Stage stage) throws Exception
    {
        String source = "rtsp://184.72.239.149/vod/mp4:BigBuckBunny_115k.mov"; // the video is weird for 1 minute then becomes stable

        primaryStage = stage;
        imageView = new ImageView();

        StackPane root = new StackPane();

        root.getChildren().add(imageView);
        imageView.fitWidthProperty().bind(primaryStage.widthProperty());
        imageView.fitHeightProperty().bind(primaryStage.heightProperty());

        Scene scene = new Scene(root, 640, 480);

        primaryStage.setTitle("Streaming Player");
        primaryStage.setScene(scene);
        primaryStage.show();

        simplePlayer = new SimplePlayer(source, this);
    }

    @Override
    public void onMediaGrabbed(int width, int height)
    {
        primaryStage.setWidth(width);
        primaryStage.setHeight(height);
    }

    @Override
    public void onImageProcessed(Image image)
    {
        LogHelper.e(TAG, "image: " + image);

        Platform.runLater(() -> {
            imageView.setImage(image);
        });
    }

    @Override
    public void onPlaying() {}

    @Override
    public void onGainControl(FloatControl gainControl) {}

    @Override
    public void stop() throws Exception
    {
        simplePlayer.stop();
    }
}

public class SimplePlayer
{
    private static volatile Thread playThread;
    private AnimationTimer timer;

    private SourceDataLine soundLine;

    private int counter;

    public SimplePlayer(String source, GrabberListener grabberListener)
    {
        if (grabberListener == null) return;
        if (source.isEmpty()) return;

        counter = 0;

        playThread = new Thread(() -> {
            try {
                FFmpegFrameGrabber grabber = new FFmpegFrameGrabber(source);
                grabber.start();

                grabberListener.onMediaGrabbed(grabber.getImageWidth(), grabber.getImageHeight());

                if (grabber.getSampleRate() > 0 && grabber.getAudioChannels() > 0) {
                    AudioFormat audioFormat = new AudioFormat(grabber.getSampleRate(), 16, grabber.getAudioChannels(), true, true);

                    DataLine.Info info = new DataLine.Info(SourceDataLine.class, audioFormat);
                    soundLine = (SourceDataLine) AudioSystem.getLine(info);
                    soundLine.open(audioFormat);
                    soundLine.start();
                }

                Java2DFrameConverter converter = new Java2DFrameConverter();

                while (!Thread.interrupted()) {
                    Frame frame = grabber.grab();
                    if (frame == null) {
                        break;
                    }
                    if (frame.image != null) {

                        Image image = SwingFXUtils.toFXImage(converter.convert(frame), null);
                        Platform.runLater(() -> {
                            grabberListener.onImageProcessed(image);
                        });
                    } else if (frame.samples != null) {
                        ShortBuffer channelSamplesFloatBuffer = (ShortBuffer) frame.samples[0];
                        channelSamplesFloatBuffer.rewind();

                        ByteBuffer outBuffer = ByteBuffer.allocate(channelSamplesFloatBuffer.capacity() * 2);

                        for (int i = 0; i < channelSamplesFloatBuffer.capacity(); i++) {
                            short val = channelSamplesFloatBuffer.get(i);
                            outBuffer.putShort(val);
                        }
                    }
                }
                grabber.stop();
                grabber.release();
                Platform.exit();
            } catch (Exception exception) {
                System.exit(1);
            }
        });
        playThread.start();
    }

    public void stop()
    {
        playThread.interrupt();
    }
}

ByteBuffer bb = ... // Your frame data is stored in this buffer
H264Decoder decoder = new H264Decoder();
Picture out = Picture.create(1920, 1088, ColorSpace.YUV_420); // Allocate output frame of max size
Picture real = decoder.decodeFrame(bb, out.getData());
BufferedImage bi = JCodecUtil.toBufferedImage(real); // If you prefere AWT image

int frameNumber = 150;
BufferedImage frame = FrameGrab.getFrame(new File("filename.mp4"), frameNumber);
ImageIO.write(frame, "png", new File("frame_150.png"));

private static void avc2png(String in, String out) throws IOException {
    SeekableByteChannel sink = null;
    SeekableByteChannel source = null;
    try {
        source = readableFileChannel(in);
        sink = writableFileChannel(out);

        MP4Demuxer demux = new MP4Demuxer(source);

        H264Decoder decoder = new H264Decoder();

        Transform transform = new Yuv420pToRgb(0, 0);

        MP4DemuxerTrack inTrack = demux.getVideoTrack();

        VideoSampleEntry ine = (VideoSampleEntry) inTrack.getSampleEntries()[0];
        Picture target1 = Picture.create((ine.getWidth() + 15) & ~0xf, (ine.getHeight() + 15) & ~0xf,
                ColorSpace.YUV420);
        Picture rgb = Picture.create(ine.getWidth(), ine.getHeight(), ColorSpace.RGB);
        ByteBuffer _out = ByteBuffer.allocate(ine.getWidth() * ine.getHeight() * 6);
        BufferedImage bi = new BufferedImage(ine.getWidth(), ine.getHeight(), BufferedImage.TYPE_3BYTE_BGR);
        AvcCBox avcC = Box.as(AvcCBox.class, Box.findFirst(ine, LeafBox.class, "avcC"));

        decoder.addSps(avcC.getSpsList());
        decoder.addPps(avcC.getPpsList());

        Packet inFrame;
        int totalFrames = (int) inTrack.getFrameCount();
        for (int i = 0; (inFrame = inTrack.getFrames(1)) != null; i++) {
            ByteBuffer data = inFrame.getData();

            Picture dec = decoder.decodeFrame(splitMOVPacket(data, avcC), target1.getData());
            transform.transform(dec, rgb);
            _out.clear();

            AWTUtil.toBufferedImage(rgb, bi);
            ImageIO.write(bi, "png", new File(format(out, i)));
            if (i % 100 == 0)
                System.out.println((i * 100 / totalFrames) + "%");
        }
    } finally {
        if (sink != null)
            sink.close();
        if (source != null)
            source.close();
    }
}