[FFmpeg-devel] [PATCH]uint16_t -> uint32_t vlc tables

Michael Niedermayer michaelni
Sun May 13 17:26:49 CEST 2007


Hi

On Sun, May 13, 2007 at 01:49:45PM +0200, Denis Fortin wrote:
> Michael Niedermayer a ?crit :
> > Hi
> > 
> > On Sun, May 13, 2007 at 12:34:01PM +0200, Denis Fortin wrote:
> >> Michael Niedermayer a ?crit :
> >>> Hi
> >>>
> >>> On Sat, May 12, 2007 at 05:54:47PM +0200, Denis Fortin wrote:
> >>>> This patch moves vlc tables from uint16_t to uint32_t.
> >>>> This is useful for vc1 which uses >16bits vlc codes.
> >>>> We this patch we don't need tables from vc1acdata.h.
> >>> rejected, wasting space and reduces speed due to data cache requirements
> >> Ok. The idea was to reuse msmpeg4 encoding part for vc1 encoding.
> >> Four tables in vc1acdata.h are duplicated from msmpeg4table.h and 
> >> h263data.h (except that they are uint32_t instead of uint16_t).
> >>
> >> Now there's two other alternatives for me :
> >> 1. Add specials cases for theses two new tables in msmpeg4.c 
> >> (find_best_tables and ac coding)
> >> 2. 'fork' msmpeg4.c into vc1enc.c and specialize function for vc1 encoding.
> >>
> >> Which one as more chances to be accepted ?
> > 
> > whats the speed (see START/STOP_TIMER) and object sizes of these 2?
> > 
> > note, i assume that both 1 and 2 is implemented without source level
> > code duplication
> About the speed and size : i have no idea and i don't plan to try both.
> For code duplication :
> #1 could be implemented (i think) with some if(){}else inside msmpeg4.c.
> #2 would be to copy and rewrite encoder functions in msmpeg4 for vc1 
> encoding only.

copy and rewrite is not ok

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

I do not agree with what you have to say, but I'll defend to the death your
right to say it. -- Voltaire
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