[Theora] Playback too slow?!

[Ivan Popov]

On Wed, Mar 30, 2005 at 12:56:00PM -0000, Alen Ladavac wrote:
> because the playback will be done on a closed platform (Xbox), so we have to
> use libtheora directly from our code. Btw, which codebase is that mmx
> decoder of yours based on? Is that the mmx branch in the Xiph SVN
> repository, or something else?

It is the decoder-only mmx patches from
http://lists.xiph.org/pipermail/theora-dev/2004-August/002348.html
(http://kyoto.cool.ne.jp/vp3/developers/theora-a3-MMXd.zip)

> I just thought you were using some magic options I don't know about. So,
> guess we are back to those peephole optimizations on the mmx decoder. We are
> looking for the best mmx implementation to base our optimizations on, and we
> are probably going to multithread it and pre-buffer about a dozen frames or

I hope you will be able to split not only decoding from visualization,
but also decoding itself into parallel threads, which would tremendously
improve performance on multicore processors.

> so, to smooth out the peaks. Any additional ideas are welcome. This just
> _has_ to work 30fps straight, no drops.

I think the eye will not distinguish between 25 and 30 fps...
you would spare quite a bit of cpu by decompressing 5 frames instead of 6.

Best regards,
--
Ivan