diff mbox series

[FFmpeg-devel,v2] avcodec/v4l2_m2m: fix setting the frame rate

Message ID 20200317112923.31053-1-ming.qian@nxp.com
State Accepted
Headers show
Series [FFmpeg-devel,v2] avcodec/v4l2_m2m: fix setting the frame rate | expand

Checks

Context Check Description
andriy/ffmpeg-patchwork success Make fate finished

Commit Message

Ming Qian March 17, 2020, 11:29 a.m. UTC
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@nxp.com>
---
 libavcodec/v4l2_m2m_enc.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

Andriy Gelman March 29, 2020, 2:53 p.m. UTC | #1
On Tue, 17. Mar 19:29, Ming Qian wrote:
> 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@nxp.com>
> ---
>  libavcodec/v4l2_m2m_enc.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/libavcodec/v4l2_m2m_enc.c b/libavcodec/v4l2_m2m_enc.c
> index c9f1741bfd..84de63ec9d 100644
> --- a/libavcodec/v4l2_m2m_enc.c
> +++ b/libavcodec/v4l2_m2m_enc.c
> @@ -172,7 +172,7 @@ static int v4l2_prepare_encoder(V4L2m2mContext *s)
>       * settingss
>       */
>      if (avctx->framerate.num || avctx->framerate.den)
> -        v4l2_set_timeperframe(s, avctx->framerate.num, avctx->framerate.den);
> +        v4l2_set_timeperframe(s, avctx->framerate.den, avctx->framerate.num);
>  
>      /* set ext ctrls */
>      v4l2_set_ext_ctrl(s, MPEG_CID(HEADER_MODE), MPEG_VIDEO(HEADER_MODE_SEPARATE), "header mode");
> -- 
> 2.17.1

v4l2m2m doesn't have a maintainer.
Any objections if I apply this patch? 

I'd set commit message to:
"The driver's frame period is incorrectly set to the frame rate. This
is fixed in the commit."

Thanks
Andriy Gelman March 31, 2020, 10:23 p.m. UTC | #2
On Sun, 29. Mar 10:53, Andriy Gelman wrote:
> On Tue, 17. Mar 19:29, Ming Qian wrote:
> > 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@nxp.com>
> > ---
> >  libavcodec/v4l2_m2m_enc.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> > 
> > diff --git a/libavcodec/v4l2_m2m_enc.c b/libavcodec/v4l2_m2m_enc.c
> > index c9f1741bfd..84de63ec9d 100644
> > --- a/libavcodec/v4l2_m2m_enc.c
> > +++ b/libavcodec/v4l2_m2m_enc.c
> > @@ -172,7 +172,7 @@ static int v4l2_prepare_encoder(V4L2m2mContext *s)
> >       * settingss
> >       */
> >      if (avctx->framerate.num || avctx->framerate.den)
> > -        v4l2_set_timeperframe(s, avctx->framerate.num, avctx->framerate.den);
> > +        v4l2_set_timeperframe(s, avctx->framerate.den, avctx->framerate.num);
> >  
> >      /* set ext ctrls */
> >      v4l2_set_ext_ctrl(s, MPEG_CID(HEADER_MODE), MPEG_VIDEO(HEADER_MODE_SEPARATE), "header mode");
> > -- 
> > 2.17.1
> 
> v4l2m2m doesn't have a maintainer.
> Any objections if I apply this patch? 
> 
> I'd set commit message to:
> "The driver's frame period is incorrectly set to the frame rate. This
> is fixed in the commit."
> 

Applied. 

Thanks,
diff mbox series

Patch

diff --git a/libavcodec/v4l2_m2m_enc.c b/libavcodec/v4l2_m2m_enc.c
index c9f1741bfd..84de63ec9d 100644
--- a/libavcodec/v4l2_m2m_enc.c
+++ b/libavcodec/v4l2_m2m_enc.c
@@ -172,7 +172,7 @@  static int v4l2_prepare_encoder(V4L2m2mContext *s)
      * settingss
      */
     if (avctx->framerate.num || avctx->framerate.den)
-        v4l2_set_timeperframe(s, avctx->framerate.num, avctx->framerate.den);
+        v4l2_set_timeperframe(s, avctx->framerate.den, avctx->framerate.num);
 
     /* set ext ctrls */
     v4l2_set_ext_ctrl(s, MPEG_CID(HEADER_MODE), MPEG_VIDEO(HEADER_MODE_SEPARATE), "header mode");