Interval option has random results.

[chrisburrus]

When trying to use the interval option, I'm getting some odd results. Interval of 1 or 2 works fine. However, with interval 3:

v4l2grab -q 100 -W 2592 -H 1944 --interval 3 -c -o test

It only takes 2 images every second, not three. If I then change interval to 4 or higher, it just takes the maximum images per second it can (between 5 and 6 for max resolution, higher if I set the resolution lower).

Any ideas what's going on? I need to set the interval to 4 if possible (I know it won't be exact, but I need approximately 4 images per second).

[chrisburrus]

FYI, this happens if you try to set the interval to higher than the max YUYV FPS of the camera, I eventually figured out.

[twam]

The program was originally not designed for high fps capture, only for stills. It internally works also with YUV so that is probably why the max. YUYV FPS of the camera matter. Feel free to improve it and open a pull request.