[FFmpeg-devel] [PATCH] vf_pad: keep a reference to the output buffer.

[Stefano Sabatini]

On date Wednesday 2012-03-07 17:23:45 +0100, Nicolas George encoded:
> Once fixed, the end_frame function does exactly
> what the default does: remove it.

The text is pretty confusing, I'd say:

Pass a picture reference to avfilter_start_frame, and remove this
reference by using the default end_frame function.

This allows the filter to keep a reference to the ouput picture in
case it is unreferenced by the following filter, as it happens with
the settb filter.

> 
> Fixes ticket #1038.
> 
> Signed-off-by: Nicolas George <nicolas.george at normalesup.org>
> ---
>  libavfilter/vf_pad.c |   11 ++---------
>  1 files changed, 2 insertions(+), 9 deletions(-)
> 
> diff --git a/libavfilter/vf_pad.c b/libavfilter/vf_pad.c
> index e226a00..9b2d5cf 100644
> --- a/libavfilter/vf_pad.c
> +++ b/libavfilter/vf_pad.c
> @@ -335,13 +335,7 @@ static void start_frame(AVFilterLink *inlink, AVFilterBufferRef *inpicref)
>      outpicref->video->w = pad->w;
>      outpicref->video->h = pad->h;
>  
> -    avfilter_start_frame(inlink->dst->outputs[0], outpicref);
> -}
> -
> -static void end_frame(AVFilterLink *link)
> -{
> -    avfilter_end_frame(link->dst->outputs[0]);
> -    avfilter_unref_buffer(link->cur_buf);
> +    avfilter_start_frame(inlink->dst->outputs[0], avfilter_ref_buffer(outpicref, ~0));
>  }
>  
>  static void draw_send_bar_slice(AVFilterLink *link, int y, int h, int slice_dir, int before_slice)
> @@ -417,8 +411,7 @@ AVFilter avfilter_vf_pad = {
>                                      .config_props     = config_input,
>                                      .get_video_buffer = get_video_buffer,
>                                      .start_frame      = start_frame,
> -                                    .draw_slice       = draw_slice,
> -                                    .end_frame        = end_frame, },
> +                                    .draw_slice       = draw_slice, },
>                                    { .name = NULL}},
>  
>      .outputs   = (const AVFilterPad[]) {{ .name       = "default",

Looks fine, assuming it passes FATE, and thanks.
-- 
FFmpeg = Fostering and Fast Mystic Puritan Enlightened God