How to decode H.264 video frame in Java environment

Question

Does anyone know how to decode H.264 video frame in Java environment?

My network camera products support the RTP/RTSP Streaming.

The service standard RTP/RTS

Answer 1

I found a very simple and straight-forward solution based on JavaCV's FFmpegFrameGrabber class. This library allows you to play a streaming media by wrapping the ffmpeg in Java.

How to use it?

First, you may download and install the library, using Maven or Gradle.

Here you have a StreamingClient class that calls a SimplePlayer class that has Thread to play the video.

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();
    }
}

SimplePlayer class uses FFmpegFrameGrabber to decode a frame that is converted into an image and displayed in your Stage

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();
    }
}