[FFmpeg-devel] Idea about speedup of startcode search

Thorsten Jordan tjordan
Fri Feb 8 15:49:40 CET 2008


Loren Merritt schrieb:
> On Fri, 8 Feb 2008, Thorsten Jordan wrote:
> 
>> Here one searches for 00 00 03 xx patterns, for mpeg 1/2 or h264 you
>> often look for 00 00 01 xx patterns or 00 00 00 01.
>>
>> This can be done in a simple C loop, but gcc does a bad job and uses up
>> to 7 instructions per scanned byte. On Core 2 Duo measurement shows 2.8
>> instructions per byte.
> 
> Which C implementation is that? It doesn't sound like you tried 
> ff_avc_find_startcode.
no, haven't tried yet.
woah, what a bizarre idea with this bit pattern :-)
ok, i guess my idea then is for /dev/null

-- 
Regards, Thorsten




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