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

Denis Fortin fortin
Sun May 13 13:49:45 CEST 2007

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.


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