[FFmpeg-devel] [PATCH] avcodec/v4l2_m2m: fix setting the frame rate

[Ming Qian]

v4l2 set the frame rate through frame intervals,
not set frame rate directly.
the frame rate and frame intervals are reciprocal.
so in libavdevice/v4l2.c we can see the following code:
	tpf->numerator   = framerate_q.den;
	tpf->denominator = framerate_q.num;

Signed-off-by: Ming Qian <ming.qian at nxp.com>
---
 libavcodec/v4l2_m2m_enc.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/libavcodec/v4l2_m2m_enc.c b/libavcodec/v4l2_m2m_enc.c
index c9f1741bfd..5b954f4435 100644
--- a/libavcodec/v4l2_m2m_enc.c
+++ b/libavcodec/v4l2_m2m_enc.c
@@ -40,8 +40,8 @@ static inline void v4l2_set_timeperframe(V4L2m2mContext *s, unsigned int num, un
     struct v4l2_streamparm parm = { 0 };
 
     parm.type = V4L2_TYPE_IS_MULTIPLANAR(s->output.type) ? V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE : V4L2_BUF_TYPE_VIDEO_OUTPUT;
-    parm.parm.output.timeperframe.denominator = den;
-    parm.parm.output.timeperframe.numerator = num;
+    parm.parm.output.timeperframe.denominator = num;
+    parm.parm.output.timeperframe.numerator = den;
 
     if (ioctl(s->fd, VIDIOC_S_PARM, &parm) < 0)
         av_log(s->avctx, AV_LOG_WARNING, "Failed to set timeperframe");
-- 
2.25.1