[MPlayer-dev-eng] liba52 vs. libac3

[Felix Buenemann]

On Monday, 17. December 2001 16:23, you wrote:
> Hi,
>
> It is planned to remove libac3 (replace by liba52) as soon as possible.
[snip]
> But...
> - libac3 has lots of 3dnow (mmx too?) optimization mostly by Nick
> - libac3 has some sse optimization (by Nick & Atmos ?)
no, they were taken from linuxvideo projects libac3 tree and merged with 
mplayers tree.

>
> Why ASAP?
> - maintaining 2 libs for teh same purpose in paralell is waste of time
>
> We need these optimized functions ported to liba52, or re-optimizing new
> code. I think it shouldn't be hard for imdct, as it's a simple, well
> defined algorithm. But for downmix, we have different goals. downmix is now
> done by decoder, but we need fast float array -> 16bit short int array
> conversion and stereo channel interleaving. I think it should be done in
> 3dnow/sse/mmx. See resample.c in liba52.
>
I vote for reoptimizing so old bugs won't be merged in.

Btw. sse optimized liba52 (as in cvs) is already faster then sse optimized 
libac3.

> Maybe i'm wrong, and it's not so simple, tell me if so.
>
> Comments welcomed...

>
> A'rpi / Astral & ESP-team

-- 
Best Regards,
	Atmos
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