[FFmpeg-devel] [PATCH] Document and validate AVFrame plane pointers.

[Reimar Döffinger]

On Fri, Feb 26, 2016 at 10:39:41PM +0100, wm4 wrote:
> On Fri, 26 Feb 2016 22:25:21 +0100
> Reimar Döffinger <Reimar.Doeffinger at gmx.de> wrote:
> 
> > Check that the required plane pointers and only
> > those are set up.
> > 
> > Signed-off-by: Reimar Döffinger <Reimar.Doeffinger at gmx.de>
> > ---
> >  libavcodec/utils.c | 14 ++++++++++++++
> >  libavutil/frame.h  |  3 +++
> >  2 files changed, 17 insertions(+)
> > 
> > diff --git a/libavcodec/utils.c b/libavcodec/utils.c
> > index af21cdd..af5ff93 100644
> > --- a/libavcodec/utils.c
> > +++ b/libavcodec/utils.c
> > @@ -885,6 +885,20 @@ static int get_buffer_internal(AVCodecContext *avctx, AVFrame *frame, int flags)
> >          avctx->sw_pix_fmt = avctx->pix_fmt;
> >  
> >      ret = avctx->get_buffer2(avctx, frame, flags);
> > +    if (ret >= 0 && avctx->codec_type == AVMEDIA_TYPE_VIDEO) {
> > +        int i;
> > +        int num_planes = av_pix_fmt_count_planes(frame->format);
> > +        for (i = 0; i < num_planes; i++) {
> > +            av_assert0(frame->data[i]);
> > +        }
> > +        // for formats without data like hwaccel allow
> > +        // pointers to be non-NULL.
> > +        for (i = num_planes; num_planes > 0 && i < num_planes; i++) {
> > +            if (frame->data[i])
> > +                av_log(avctx, AV_LOG_ERROR, "Buffer returned by get_buffer2() did not zero unused plane pointers\n");
> > +            frame->data[i] = NULL;
> > +        }
> > +    }
> >  
> 
> Can you move it to a separate function? Say, ff_verify_frame(). This
> could get much more complicated too when checking AVBufferRef usage or
> audio.

Why ff_? If we've decided on it and use it in other places it
might become a av_* function in libavutil.
But until then I guess it should be a static function in that file?