[FFmpeg-devel] [PATCH v5 1/7] avcodec/v4l2_context: don't reinit output queue when dynamic resolution change

[Andriy Gelman]

On Tue, 04. Jan 17:08, Ming Qian wrote:
> in the v4l2 stateful video document, we can see the following
> description:
>     During the resolution change sequence, the OUTPUT queue must remain
>     streaming. Calling VIDIOC_STREAMOFF() on the OUTPUT queue would
>     abort the sequence and initiate a seek.
> 
>     In principle, the OUTPUT queue operates separately from the CAPTURE
>     queue and this remains true for the duration of the entire
>     resolution change sequence as well.
> 
> so don't reinit the output queue when handling the resolution change
> event
> 
> Signed-off-by: Ming Qian <ming.qian at nxp.com>
> ---
>  libavcodec/v4l2_context.c | 27 ++-------------------------
>  1 file changed, 2 insertions(+), 25 deletions(-)
> 
> diff --git a/libavcodec/v4l2_context.c b/libavcodec/v4l2_context.c
> index ff1ea8e57b08..dda5157698c3 100644
> --- a/libavcodec/v4l2_context.c
> +++ b/libavcodec/v4l2_context.c
> @@ -162,9 +162,8 @@ static int v4l2_handle_event(V4L2Context *ctx)
>  {
>      V4L2m2mContext *s = ctx_to_m2mctx(ctx);
>      struct v4l2_format cap_fmt = s->capture.format;
> -    struct v4l2_format out_fmt = s->output.format;
>      struct v4l2_event evt = { 0 };
> -    int full_reinit, reinit, ret;
> +    int reinit, ret;
>  
>      ret = ioctl(s->fd, VIDIOC_DQEVENT, &evt);
>      if (ret < 0) {
> @@ -180,25 +179,12 @@ static int v4l2_handle_event(V4L2Context *ctx)
>      if (evt.type != V4L2_EVENT_SOURCE_CHANGE)
>          return 0;
>  
> -    ret = ioctl(s->fd, VIDIOC_G_FMT, &out_fmt);
> -    if (ret) {
> -        av_log(logger(ctx), AV_LOG_ERROR, "%s VIDIOC_G_FMT\n", s->output.name);
> -        return 0;
> -    }
> -
>      ret = ioctl(s->fd, VIDIOC_G_FMT, &cap_fmt);
>      if (ret) {
>          av_log(logger(ctx), AV_LOG_ERROR, "%s VIDIOC_G_FMT\n", s->capture.name);
>          return 0;
>      }
>  
> -    full_reinit = v4l2_resolution_changed(&s->output, &out_fmt);
> -    if (full_reinit) {
> -        s->output.height = v4l2_get_height(&out_fmt);
> -        s->output.width = v4l2_get_width(&out_fmt);
> -        s->output.sample_aspect_ratio = v4l2_get_sar(&s->output);
> -    }
> -
>      reinit = v4l2_resolution_changed(&s->capture, &cap_fmt);
>      if (reinit) {
>          s->capture.height = v4l2_get_height(&cap_fmt);
> @@ -206,18 +192,9 @@ static int v4l2_handle_event(V4L2Context *ctx)
>          s->capture.sample_aspect_ratio = v4l2_get_sar(&s->capture);
>      }
>  
> -    if (full_reinit || reinit)
> +    if (reinit)
>          s->reinit = 1;
>  
> -    if (full_reinit) {
> -        ret = ff_v4l2_m2m_codec_full_reinit(s);
> -        if (ret) {
> -            av_log(logger(ctx), AV_LOG_ERROR, "v4l2_m2m_codec_full_reinit\n");
> -            return AVERROR(EINVAL);
> -        }
> -        goto reinit_run;
> -    }
> -
>      if (reinit) {
>          if (s->avctx)
>              ret = ff_set_dimensions(s->avctx, s->capture.width, s->capture.height);
> -- 
> 2.33.0

lgtm

Thanks,
-- 
Andriy