[vorbis-dev] Parallelism

[Jeff Squyres]

Greetings.

In looking through the mail archives, I don't see any mention of
parallelism of the vorbis code (particularly the encoder).  I was
wondering if anyone was looking into this at all?  Either with threads,
and/or on some kind of parallel machine (e.g., a Beowulf cluster)?  I see
very little mention of threads in the source code, which leads me to
believe that they are only there for their respective frameworks (e.g.,
the xmms plugin).

I ask because I would probably be willing to help in this department.  I
am a maintainer of one of the freeware implementations of the Message
passing Interface (MPI) -- LAM/MPI.  As such, I know a bit about parallel
programming, both with threads and with MPI.  Indeed, several months ago I
did a naieve implemenation of parallelizing the bladeenc MP3 encoder
(bladeenc was the first encoder that I found in a web search).  I don't
claim to understand much of the MP3 process (indeed, one of the
assumptions that I used about the MP3 encoding process in parallelizing
bladeenc turned out later to be false.  Oops. :-), but the parallelism
does seem to work, and does give mostly linear speedup as you add more
CPUs.

So if this group is willing, I can help out (yes, with code :-) with the
parallelism -- although I will need help understanding the algorithms,
etc.  I give the following URLs as reference:

        http://www.mpi.nd.edu/~jsquyres/bladeenc/
        - The parallel version of the bladeenc encoder, with lots of
          explanations
        http://www.mpi.nd.edu/lam/
        - The main LAM/MPI web site
        http://www.mpi-forum.org/
        - The main MPI web site (contains the specs, etc.)

Thanks for your time.

(I've read some of the vorbis sites and the archives of this list, but I'm
still a newbie here -- forgive me if I asked stupid things or if this list
isn't the appropriate place for this post :-)

{+} Jeff Squyres
{+} squyres at 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"

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