What fraction of work is iDCT?

Christophe Massiot massiot at via.ecp.fr
Mon Jun 25 19:23:42 CEST 2001


On Mon, Jun 25, 2001, Eugenio Jarosiewicz wrote:

> Ok, so someone else who knows more about this than me already gave you
> some #'s.  But of quite interest might be:
> 
> Altivec IDCT sample plus much more...
> 
> http://developer.apple.com/hardware/ve/examples.html
> 
> http://developer.apple.com/hardware/ve/
> 
> ( I wish I had done a more completesearch earlier )
> 
> Jeff - have you taken a look this?  I'm very interested about getting
> this into VLC for OSX and ppc in general.  I don't know much about
> vector processing but the concept seems fairly straightforward.

If I remember well, I think this is the code I borrowed for the
currently-broken vdec_idct_altivec.c. There was apparently a deadlock
in the code (?). One of my mistakes was that I forgot (or misplaced) the
matrix transpose at the beginning, and I haven't had time (nor a machine)
to debug it.

> ps - Christophe - figure you'll be interested in this - do you have
> any time to help out if needed ;-) ?

Well, you can still ask me questions, but I don't have an OS X machine
to test it - and BTW I'm going on vacation for 2 weeks on thursday, so
be quick :-).

-- 
Christophe Massiot.




More information about the vlc-devel mailing list