Question

This code snippet is supposed to save part of a video whose range is defined by start and end. There is an array of structures (data[i]) that holds the starting and end frame of a video shot in the original video. There are total of 8 shots.

for (int i = 0; i < finalCount-1; ++i) {
    capture = cvCaptureFromAVI("Stats\\Shots\\Cricketc1.avi");
    assert(capture);

    int frame_number = 0;
    int start = data[i].start_frame;
    int end   = data[i].end_frame;

    char shotname[100];
    strcpy_s(shotname, "shot_");
    char shot_id[30];
    _itoa_s(data[i].shot_no, shot_id, 10);
    strcat_s(shotname, shot_id);
    strcat_s(shotname, ".avi");

    IplImage* image = NULL;

    CvVideoWriter* writer = NULL;
    writer = cvCreateVideoWriter (shotname, CV_FOURCC('i','Y','U','V'), fps, cvSize(width, height), 1);
    assert(writer);
    while (frame_number >= start && frame_number < end) {
        image = cvQueryFrame(capture);
        assert(image);
        cvWriteFrame(writer, image);
    }
    cvReleaseImage(&image);
    cvReleaseVideoWriter(&writer);
    cvReleaseCapture(&capture);
    cout << shotname << " saved ..." << endl;
}

After running the program 8 video files are created that have a size of 6kb and do not run. I have tried various codecs like divx, mjpg, mpg2, iyuv etc but all give the same result.

Answer 1

If Gunther Fox answer won’t help try to use different codec – it’s very strange, but in my situation iyuv is not working at all and some other codecs works ok, but i can’t read them while debugging… For me – ms video and radius cinepak always works fine(writing and reading), iyuv is not working at all, other codes – writing and reading, but not while debugging.