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Hi,

I think your code is right. Sample Java code is as below. I also tried on lots of environments like you. With Gstream ugly & good codecs on Ubuntu 12.04, H.264 streaming is working with a latency without any frame corruption.

The code is like that :

public static void main(String[] args) {

    ImageIO.setUseCache(false);
    JFrame jframe = new JFrame("ETS New Algorithm - Suzuki85");
    jframe.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    JLabel vidpanel = new JLabel();
    jframe.setContentPane(vidpanel);
    jframe.setSize(1280, 720);
    jframe.setVisible(true);

    Mat frame = new Mat();
    VideoCapture camera = new VideoCapture("rtsp://192.168.1.229:554/av0_1");
    while (true) {
        if (camera.read(frame)) {
                ImageIcon image = new ImageIcon(Mat2bufferedImage(frame));
                vidpanel.setIcon(image);
                vidpanel.repaint();
            }
    }
}

public static BufferedImage Mat2bufferedImage(Mat image) {
    MatOfByte bytemat = new MatOfByte();
    Highgui.imencode(".jpg", image, bytemat);
    byte[] bytes = bytemat.toArray();
    InputStream in = new ByteArrayInputStream(bytes);
    BufferedImage img = null;
    try {
        img = ImageIO.read(in);
    } catch (IOException e) {
        e.printStackTrace();
    } finally {
        bytemat.release();
        bytes = null;
    }
    return img;
}

But if you need to process data (for example; motion tracking, histogram equalization etc. i mean Highgui procs) you need the Mat reference and this reference can not be gotten without FFMPEG. And OpenCV which is built from source with FFMPEG ability uses CPU more than 100% on Linux.So, you can not run properly on Linux. (Some folks said that they were succedded here and was me..:) but FFMPEG Needed not GStreamer but i couldn't get a stable environment)

So, i choosed to go on Win7 64 bit platform wt. OpenCV 2.4.11. Currently i can get MJPEG streming wt. 1920x1080 resolution at 16384 bitrate from my ip camera. Its quality is near to H.264 but data cost is twice of H.264. (H.264 = 500K, MJPEG = 800K) I also downloaded source code of OpenCV2.4.11 and open the project in Visual Studio .NET. I succedded to compile it and currently i am investigating the source code at CPP side if i will be able to find anything, i may write to here.

I saw that lots of codes exist at CPP side about comparing the FFMPEG versions. Sample like that :

And lastly, you are right that MPEG4 or H.264 encoded files on disk are played without any error.

IP Camera H.264 640x480 RTSP Sample on Win7 64 bit and OpenCV2.4.11 (wt. Rendering errors)

H.264 Encoded MP4 File 640x480 Sample on Win7 64 bit and OpenCV2.4.11 (wt. out errors)

I guess the problem is related to network side. If it was related to FFMPEG, the H.264 encoded file also rendered wt. errors. GStreamer on Linux can render it wt. out errors with a latency. So, I think if grapb - retrieve cylec can wait some time about being sure that the frame is gotten properly than there will be no problem. I mean i can accept 2-3 seconds delay if Mat reference will be able to be given after reading the H..264 encoded video data.

See you on the next conversation...:) Regards,

Eray