set v4l2 framerate

framerate.c

bool set_framerate(int fd)

    struct v4l2_streamparm parm;

    parm.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;

    parm.parm.capture.timeperframe.numerator = 15;
    parm.parm.capture.timeperframe.denominator = 1;

    int ret = xioctl(fd, VIDIOC_S_PARM, &parm);

    if (ret < 0)
    {
        return false;
    }

    return true;
}

The values in numerator and denominator should be flipped. This will always result in 1fps, rather than the intended 15fps.