OpenCv:u!=0 Exception while reading frames from video file

问题

I'm trying to get frames from a video file but while reading frames, OpenCv:u!=0 exception is being thrown. I'm using Emgu.Cv dll. I have written the code as follows:

private void GetVideoFrames(String Filename)
{
    try
    {
        captureFrame = new Capture(Filename);
        bool Reading = true;
        while (Reading)
        {
            using (frame = captureFrame.QueryFrame().ToImage<Bgr, Byte>())
            {
                if 
                if (frame != null)
                {
                    imageBox1.Image = frame;
                    frameCount++;
                }
                else
                {
                    Reading = false;
                }
            }
        }
    }

Could anyone please provide some help.

回答1:

according to me, you should make a copy of frame grabbed from camera. You could you the following code. It is tested and error free.

    Capture captureFrame = new Capture(Filename);
    Mat frame = new Mat();
    Mat frame_copy = new Mat();

    //Capture Image from file
    private void GetVideoFrames(String Filename)
    {
        try
        {
            captureFrame = new Capture(Filename);
            captureFrame.ImageGrabbed += ShowFrame;
            captureFrame.Start();
        }
        catch (Exception ex)
        {
            MessageBox.Show(ex.ToString());
        }
    }

    //Show in ImageBox
    private void ShowFrame(object sender, EventArgs e)
    {
        captureFrame.Retrieve(frame);
        frame_copy = frame;
        imageBox1.Image = frame_copy ;
    }

回答2:

May be you need to release memory. Ex. frame.Release();

来源：https://stackoverflow.com/questions/41612852/opencvu-0-exception-while-reading-frames-from-video-file