[Theora-dev] Re: MMX/mmxext optimisations

Jim Darby jim at jimbocorp.uklinux.net
Wed Aug 25 14:10:22 PDT 2004

On Tue, 2004-08-24 at 11:54, Adam D. Moss wrote:

> One down size is that to my eye, mmx-encoded theora videos are
> slightly blurrier than their standard counterparts, for a fixed
> target bitrate.  Also, for a fixed quality factor, the files seem
> quite a lot smaller (but not particularly worse-looking on brief
> inspection, which is odd and counter-intuitive given the first
> observation, but I'm not complaining).

This is a little worrying. Surely the MMX code should just make things
happen faster rather than different?

I would have though that encoding/decoding the same file should produce
the same output irrespective of the MMX optimisations. Are all, it's
just the same operations but FASTER, isn't it?


Jim Darby <jim at jimbocorp.uklinux.net>
The Jimbo Corporation
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