[Ffmpeg-devel] [PATCH] SIMD accelected SNOW decoding

[Michael Niedermayer]

Hi

ok, not a real review, just some quick comments to prevent me from (ab)using
cvs admin -o

On Sun, Nov 27, 2005 at 10:41:26PM +0100, Guillaume POIRIER wrote:
[...]
> Index: snow.c
> ===================================================================
> RCS file: /cvsroot/ffmpeg/ffmpeg/libavcodec/snow.c,v
> retrieving revision 1.63
> diff -u -r1.63 snow.c
> --- snow.c	21 Sep 2005 23:09:16 -0000	1.63
> +++ snow.c	27 Nov 2005 21:34:45 -0000
> @@ -25,6 +25,11 @@
>  
>  #include "mpegvideo.h"
>  
> +#ifdef HAVE_MMX
> +#include "i386/mmx.h"
> +#include "i386/snow_mmx_sse2.h"
> +#endif

ugh, this is not acceptable, (iam pretty sure i already said so 6month ago)
cpu specific stuff goes in the various subdirectories under libavcodec and
is called over function pointers through DSPContext or a new struct, doing
it the way its done here is a incredible mess, just think about what will
happen if ppc,alpha,sparc,... optimizations are added


[...]
> +int min = 999999;

hmm


[...]
>  //            int am= 18*(a2+a3) - 2*(a1+a4);
> +//            int am = 16*(a2+a3);
>  //             int aL= (-7*a0 + 105*a1 + 35*a2 - 5*a3)>>3;

cosmetics ...

> -assert(src_stride > 2*MB_SIZE + 5);
> +assert(src_stride > 7*MB_SIZE);

now that means that snow would no longer support videos with width<=224 ...

-- 
Michael