[FFmpeg-devel] [PATCH 2/3] Indeo 5 decoder: common DSP functions
Sun Jan 10 12:22:17 CET 2010
On Sat, Jan 09, 2010 at 05:43:40PM +0200, Kostya wrote:
> On Sat, Jan 09, 2010 at 03:47:39PM +0100, Michael Niedermayer wrote:
> > On Sat, Jan 09, 2010 at 04:40:30PM +0200, Kostya wrote:
> > > On Fri, Jan 08, 2010 at 11:41:23PM +0100, Michael Niedermayer wrote:
> > > > On Sun, Jan 03, 2010 at 12:56:36PM +0200, Kostya wrote:
> > > > [...]
> > > > > void ff_ivi_recompose53(const IVIPlaneDesc *plane, uint8_t *dst,
> > > [function body skipped]
> > > >
> > > > is this mess faster than some more readable variant?
> > >
> > > Here's more readable variant by me, checked to be bitexact but it's
> > > significantly slower (> 10%), I'd rather leave old one.
> > I also prefer speed, what about an implementation using lifting?
> I'll try to implement it.
Hmm, after some experiments I'd rather leave original version.
Even grouping variables together in array gives significant performance
drop. And pure lifting transform is not applicable here either because
band data is grouped and it will take at least two passes (hor/vert)
with conditions for missing bands and requires an additional temp
> > [...]
> > --
> > Michael GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB
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