[libdv-dev] RE: libdv and the intel mmx iDCT

[Erik W. <om...@cs...>]

On Thu, 27 Apr 2000 Mat...@no... wrote:

> May I ask what performance your decoder have at the moment. The raw decoder
> performance, not including such things as drawing picture on screen etc. I
> do not have access to cvs (firewall issues) so i cannot download and try it
> myself.

I just timed the current CVS version (with some new asm code as of last
night) at 2.5 seconds for 30 frames.  This doesn't include yuv2rgb or
display, just the decode itself.  This is on a PIII/500 coppermine laptop.

The major performance issues are the parse code, the brute-force idct
2-4-8 (which should be solved by Tuesday, hopefully), and the fact that a
lot of the stuff hasn't been collapsed yet from the naive
correctness-over-all implementation.  For instance, inverse quantization
is taking 10% of the time because it hasn't been merged with idct yet.

I've put a snapshot up on ftp.libdv.sourceforge.net for you.  It's a fresh
checkout of CVS, tar'd.  You can also download pond.dv from there, which
is what I did the aforementioned benchmark with.

TTYL,
    Omeag

         Erik Walthinsen <om...@cs...> - Staff Programmer @ OGI
        Quasar project - http://www.cse.ogi.edu/DISC/projects/quasar/
   Video4Linux Two drivers and stuff - http://www.cse.ogi.edu/~omega/v4l2/
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