[FFmpeg-devel] [PATCH] VC1 VDPAU: Mark missing reference frames as such.

[Michael Niedermayer]

On Tue, Oct 01, 2013 at 08:04:34AM +0200, Reimar Döffinger wrote:
> 
> 
> On 01.10.2013, at 03:15, Michael Niedermayer <michaelni at gmx.at> wrote:
> 
> > On Sat, Sep 28, 2013 at 11:13:35AM +0200, Reimar Döffinger wrote:
> >> Currently the code passes some nonsense values as
> >> references instead, causing corruption with NVidia's
> >> and assertion failures with Mesa's implementation.
> >> For non-corrupted input this mostly happens in
> >> interlaced bitstreams, e.g.
> >> http://samples.mplayerhq.hu/V-codecs/WMV9/interlaced/480i30__codec_WVC1__mode_2__framerate_29.970__type_2__preproc_17.wmv.
> >> The != VDP_INVALID handle assert does not trigger
> >> (and probably is quite nonsense) because the frames
> >> are initialized to 0.
> >> 
> >> Signed-off-by: Reimar Döffinger <Reimar.Doeffinger at gmx.de>
> >> ---
> >> libavcodec/vdpau_vc1.c | 4 ++++
> >> 1 file changed, 4 insertions(+)
> >> 
> >> diff --git a/libavcodec/vdpau_vc1.c b/libavcodec/vdpau_vc1.c
> >> index 272b2d9..c6e3343 100644
> >> --- a/libavcodec/vdpau_vc1.c
> >> +++ b/libavcodec/vdpau_vc1.c
> >> @@ -44,14 +44,18 @@ static int vdpau_vc1_start_frame(AVCodecContext *avctx,
> >> 
> >>     switch (s->pict_type) {
> >>     case AV_PICTURE_TYPE_B:
> >> +        if (s->next_picture_ptr) {
> >>         ref = ff_vdpau_get_surface_id(&s->next_picture);
> >>         assert(ref != VDP_INVALID_HANDLE);
> >>         info->backward_reference = ref;
> >> +        }
> >>         /* fall-through */
> >>     case AV_PICTURE_TYPE_P:
> >> +        if (s->last_picture_ptr) {
> > 
> > vc1 contains quite a few NULL checks on srcy/uv, that is
> > picture.f.data[0]
> > dunno if that can be used here too
> 
> data[0] can validly be 0 as far as I can tell.
> Also I check the _ptr ones because that's what the VC1 code I looked at did.

patch should be ok ten

[...]
-- 
Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

Republics decline into democracies and democracies degenerate into
despotisms. -- Aristotle
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