How to play any video with a fixed frame rate (fps) using OpenCV?

Question

Is there any way or function in OpenCV that allows us to play any video with a fixed frame rate(fps)? Different videos may have different frame rates but by using OpenCV library can we play them by a fixed frame rate that we define?

Thanks in advance.

Answer 1

Take a look at this article. It shows how to play back AVI files with OpenCV. Here, the frame rate is read using

int fps = ( int ) cvGetCaptureProperty( capture, CV_CAP_PROP_FPS );

and the delay is set via

key = cvWaitKey( 1000 / fps );

Hence, by controlling the fps variable, you can get the play back rate you want.

Answer 2

int fps = (int)cvGetCaptureProperty(capture, CV_CAP_PROP_FPS);
int delay = 1000 / fps;

while (true) {
    clock_t startTime = clock();

    capture.read(frame);
    process();

    imshow("video", frame);

    while (clock() - startTime < delay) {
        waitKey(1);
    }
}