On Wed, May 25, 2022 at 05:53:12PM +0200, Michael Niedermayer wrote:
> On Tue, May 24, 2022 at 08:50:51PM +0200, Andreas Rheinhardt wrote:
> > Michael Niedermayer:
> > > Fixes: CID1435168
> > > 
> > > Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
> > > ---
> > >  libavcodec/vc1_loopfilter.c | 5 +----
> > >  1 file changed, 1 insertion(+), 4 deletions(-)
> > > 
> > > diff --git a/libavcodec/vc1_loopfilter.c b/libavcodec/vc1_loopfilter.c
> > > index 0f990cccef..ee694ede28 100644
> > > --- a/libavcodec/vc1_loopfilter.c
> > > +++ b/libavcodec/vc1_loopfilter.c
> > > @@ -1125,10 +1125,7 @@ static av_always_inline void vc1_b_h_intfi_loop_filter(VC1Context *v, uint8_t *d
> > >          dst = dest + (block_num & 2) * 4 * s->linesize + (block_num & 1) * 8;
> > >  
> > >      if (!(flags & RIGHT_EDGE) || !(block_num & 5)) {
> > > -        if (block_num > 3)
> > > -            v->vc1dsp.vc1_h_loop_filter8(dst + 8, linesize, pq);
> > > -        else
> > > -            v->vc1dsp.vc1_h_loop_filter8(dst + 8, linesize, pq);
> > > +        v->vc1dsp.vc1_h_loop_filter8(dst + 8, linesize, pq);
> > >      }
> > >  
> > >      tt = ttblk[0] >> (block_num * 4) & 0xf;
> > 
> > Are you certain that the current code is actually correct or whether
> > something else was intended?
> 
> iam not certain no but the vc1_b_v_intfi_loop_filter() function also
> treats luma and chroma the same
> 
>     if(!(flags & BOTTOM_EDGE) || block_num < 2)
>         v->vc1dsp.vc1_v_loop_filter8(dst + 8 * linesize, linesize, pq);
> 
> this is just the matching function for horizontal instead of vertical
> 
> also whan looking at the 4x4 4x8 and 8x4 cases i see no difference
> between horizontal and vertical for intfi. But ultimately yes of course
> it could be buggy and something else could be correct.
> 
> but if i replace this by an abort()
> make: *** [fate-vc1_sa10143] Error 134
> make: *** [fate-vc1_ilaced_twomv] Error 134
> 
> Fate fails, so it should be tested

will apply this unless someone has some further insight in this or objection
as i just run into this again

thx

[...]

-- 
Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

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