[FFmpeg-devel] dealing with tables in DV codec

Måns Rullgård mans
Wed Sep 10 21:27:33 CEST 2008

Diego Biurrun <diego at biurrun.de> writes:

> On Wed, Sep 10, 2008 at 08:22:41AM +0100, M?ns Rullg?rd wrote:
>> Diego Biurrun <diego at biurrun.de> writes:
>> > On Tue, Sep 09, 2008 at 01:51:06PM -0700, Roman Shaposhnik wrote:
>> >> 
>> >> as I promised, I tried to come with alternative ways of dealing
>> >> with macroblock placement in DV codec, and it seems that no
>> >> matter what I use on Xeon and Opteron it is basically a toss up.
>> >> There's no speed gain, there's no speed loss. The tables can
>> >> go so it is a net gain. Now, on SPARC I see a stable speed 
>> >> loss of about ~3% or so. And I suspect that the same will
>> >> be true on any chip with a low clock speed.
>> >> 
>> >> Now, I'm publishing a temporary diff to solicit public comments
>> >> on how the calculations can be optimized even further. If nobody
>> >> comes up with any kind of good ideas -- I don't know what to do.
>> >> Michale has always told us that even ~3% is significant enough. 
>> >> So it needs to be dealt with before any change can occur.
>> >
>> > I don't think SPARC is important.  Let me know what I will have to do
>> > and I will benchmark on my trusty old K6-III 500.  Then you will have
>> > numbers for a low clock speed x86 system.
>> Who gets to decide which machines are important?  Is K6-3 more
>> important than SPARC?
> x86 is surely more important than SPARC


> and a K6-III is an x86 processor with relatively low clock speed...

Yes, and?

M?ns Rullg?rd
mans at mansr.com

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