[FFmpeg-devel] libavutil simd

[Luca Barbato]

Rich Felker wrote:
> On Tue, Oct 02, 2007 at 01:04:02AM +0200, Luca Barbato wrote:
>>> If certain users really need the
>>> optimizations they can compile a build specific to their cpu or else
>>> install a special binary package. This is how the Linux kernel already
>>> works on most (all?) distributions, and we'd have a lot fewer packages
>>> per arch than Linux does, probably.
>> No, the opposite, everybody but g3 users want to have altivec...
> 
> Ah.. WTF does MPlayer even run on such slow stuff? It's kinda like
> asking MPlayer to run on pre-MMX pentiums. Sure it will work but the
> biggest movie you could play is 64x48 mpeg1... I expect g3 is a bit
> better but not much.

not really. no. ^^ (a non altivec ppc cpu can pretty much decode mpeg4
w/out many issues...)

> The application should be able to either call a function to detect the
> cpu capabilities, or provide its own set if it already detected them
> in a different way.
> 
> Alternatively, if there's a reliable way such as /proc/cpuinfo to
> detect them (reliable meaning no false positives, not no false
> negatives) then we probably don't even need this. IMO it's safe for a
> library to open and read /proc/cpuinfo. It's not safe for a library to
> fork and/or set signal handlers.

/proc/cpuinfo is available just on linux... well the other os I know
running on ppc have already other means to tell they are running altivec...

lu

-- 

Luca Barbato

Gentoo/linux Gentoo/PPC
http://dev.gentoo.org/~lu_zero