On 05 July 2006 19:11, Rene Rebe wrote:
> Hi,
>
> On Wednesday 05 July 2006 19:57, Mike Stump wrote:
>> On Jul 4, 2006, at 7:43 PM, [EMAIL PROTECTED] wrote:
>>> The codec is at http://www.sourceforge.net/projects/openavs/.
>>> Currently, it requires a 3Ghz or better CPU to get a resonable
>>> framerate. I would like the codec to be useful even on 586 ( 1Ghz or
>>> so ). Any ideas?
>>
>> Recode slower parts in assembler or punt to video card.
>
> Aside the general com.lang.c boilderplate (...) usually it is
> already a gain to rewrite inefficent algorithms with something
> more clever and to use gcc SIMD vector extensions.
I believe Lionel's real problem is likely to be that he was hoping that
turning on the "-mmx -sse -sse2 -3dnow" options would auto-vectorise his code
for him.
Lionel, (IIUIC) those options just /enable/ the use of the various SIMD
features; they don't adjust your code to use those features if it doesn't do
so already, so apart from a fairly small speed-up on some floating point
operations that can be done more efficiently in the mmx unit, you shouldn't
have been expecting to see much difference in the first place.
cheers,
DaveK
--
Can't think of a witty .sigline today....
