Re: Demo

[Jeff Squyres <jsquyres@lsc.nd.edu>]

On 30 Apr 2001, Dale Southard wrote:

> > We are using Linux and MPI (LAM).
>
> Several have already suggested the pov-ray stuff, but if you'd rather
> have sound than pictures, the LAM/MPI maintainer has parallelized both
> the BladeEnc MP3 encoder and a version of the OggVorbis encoder:
>
>   http://www.mpi.nd.edu/~jsquyres/bladeenc/
>   http://www.mpi.nd.edu/~jsquyres/vorbis/
>
> Both are likely to work well with LAM/MPI.  :-)

Thanks for the referral!  :-)

I should note that the Vorbis encoder work has been done, but it turns out
that the internals of the vorbis libraries have things that inherently
make them un-parallelizable... at least at the moment (perhaps this will
finally inspire me to update my vorbis web pages!).  Apparently, there's
some deep mojo about the "noise" calculation within the guts of vorbis
where successive blocks of audio samples are at least somewhat dependant
on each other.

As such, I have a "working" multi-threaded parallel vorbis encoder, but I
never released it because the output has clicks in it.  The vorbis folks
are aware of this, and it will likely be fixed someday, but I don't think
it's at the top of their to-do list.  :-\

{+} Jeff Squyres
{+} squyres@cse.nd.edu
{+} Perpetual Obsessive Notre Dame Student Craving Utter Madness
{+} "I came to ND for 4 years and ended up staying for a decade"