Re: About xvid source assembly language optimize(why it does not work?)

Michael Militzer <[email protected]>
Newsgroups gmane.comp.video.xvid.devel
Message-ID <[email protected]>
Hi,

make sure you really compiled xvid with assembly optimizations enabled. You
need yasm or nasm present - or otherwise xvid will be compiled with c-code
only.

Also note that the -m option will write out data to your disk. It might be
that more time is spent on I/O than on the actual decoding. In that case,
asm and noasm options could seem to perform similar.

Regards,
Michael


Quoting ?? <[email protected]>:

> Dear  Everybody:
>
>    I download the  xvid 1.1.3 source code , and i compiled the   
> source  under Fedora Core 8.
>   Then I compile xvid_decraw.c.
>   And I run with the command:
>
>   ./xvid_decraw   -i input.m4v   -m
>   then it work well, and output the bitmap file. but it is rather slow.
>   Then I use the command below:
>   ./xvid_decraw   -i input.m4v   -asm -m
>   Hence I think i used  -asm option ,  the decoding speed should be   
>  accelerated.
>
>   But .... I find that the result is unchanged with the  non-asm   
> execution result .
>
>   input.m4v is a raw 720x568 mpeg4 video sequence, .
>
>   I wonder whether the -asm  option worked!
>
>   So i test  the fdct and idct, they have been assigned to    
> fdct_mmx_skal and idct_mmx respectly.
>
>   But why it does not accelerate?
>
>   So i use a small script to test the  fdct_c and  fdct_mmx_skal.    
> To run 1000000 times ,
>   the fdct_c consume 2.7 seconds  and fdct_mmx_skal need 0.8 second   
> on my computer.
>   It seems that asm code should be much faster.  But why xvid   
> decoding can not be speeded up?
>
>   Thanks very much !
>
>
>
> 2008-11-18
>
>
>
> Ice Lee
> _______________________________________________
> XviD-devel mailing list
> [email protected]
> http://list.xvid.org/mailman/listinfo/xvid-devel
>
>
lmpx.com only provides a reader for public news (NNTP) servers. It is not affiliated with the servers or forums shown here and is not responsible for the content of articles, which is written by their respective authors.