From 9889a1223028a14ac2fd56323fc813b62087c918 Mon Sep 17 00:00:00 2001 From: Paul Elder Date: Tue, 28 Aug 2018 02:10:01 -0400 Subject: v4l2: add v4l2_set_frame_rate We would like to be able to set the frame rate of video sources. This patch adds such a function for v4l2-based video sources to use. Signed-off-by: Paul Elder Reviewed-by: Laurent Pinchart Reviewed-by: Kieran Bingham --- lib/v4l2.c | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) (limited to 'lib/v4l2.c') diff --git a/lib/v4l2.c b/lib/v4l2.c index 9030270..de6ed88 100644 --- a/lib/v4l2.c +++ b/lib/v4l2.c @@ -500,6 +500,26 @@ int v4l2_set_format(struct v4l2_device *dev, struct v4l2_pix_format *format) return 0; } +int v4l2_set_frame_rate(struct v4l2_device *dev, unsigned int fps) +{ + struct v4l2_streamparm parm; + int ret; + + memset(&parm, 0, sizeof parm); + parm.type = dev->type; + parm.parm.capture.timeperframe.numerator = 1; + parm.parm.capture.timeperframe.denominator = fps; + + ret = ioctl(dev->fd, VIDIOC_S_PARM, &parm); + if (ret < 0) { + printf("%s: unable to set frame rate (%d).\n", dev->name, errno); + return -errno; + } + + dev->fps = fps; + return 0; +} + /* ----------------------------------------------------------------------------- * Buffers management */ -- cgit v1.2.3