Re: G3's, G4's, Altivec, DVD's, iBooks, and TiBooks

[Benjamin Herrenschmidt <benh@kernel.crashing.org>]

>  A PII/266 with a Rage128(not pro) can sustain 20fps on DVDs under Linux.
>There is no good reason a G3/366 can't do the same. And a 500 or 600 should
>be able to go all the way.  That is just using the hardware colorspace, not
>even using iDCT or motion comp.  
>  I have my doubts that Apple is even using those features, because if you
>try to play a DVD under OS9 or OSX it will make the system unusable. You
>watch the DVD and that's all you do. Might just be playing scheduling tricks
>though.

I'm pretty sure Apple uses them, just see the difference of playback
smoothness between an ATI based MacOS and an nVidia one (nVidia don't
do all the fancy HW accelerations there).

One big issue is the time it takes to blit the frames to the
framebuffer. Note that I think the new revision of UniNorth AGP in
the new tiBook (and possibly in the ibook2's) can do x4 and can do
write combining (which along AGP fastwrite, if implemented, can
really improve things).

Ben.