From: Gaspard Bucher <gaspard@...>
Date: 2007-10-21T17:22:24+09:00
Subject: Re: embed Ruby or Lua

>
> I'm not quite sure *exactly* what it is you're trying to do here, but my
> rough guess is that it's real-time multimedia. Judging by some of the
> other things on the site -- support vector machines, BLAS, etc. -- I
> think you probably know enough to code the whole thing in C or C++, and
> if you can do so, that's what I'd recommend.

All the core parts are coded in C. I need a scripting language for the
post-processing (simple low-pass filter, decision tree, instrument
change depending on song position, etc).

>
> In fact, I'd recommend getting one of the Linux audio distributions,
> like JAD or Studio 64, and getting the real "hard real-time" (as hard
> real-time as Linux can get, anyhow) libraries up and running. I've
> mostly looked at Studio 64 because I have a 64-bit machine, but JAD is
> also good. Both are Debian Linux based and have special kernel patches
> and other software for low-latency audio processing.

This would be great, but the machine has to include the
sound-generating application (I bought mac-minis). If the latency is
too bad, I might use Studio64 and send all the midi to a central
"audio-generation" machine.


>
> Lua is probably a good bit faster than Ruby, but I don't know how much
> of the application has to be in the scripting language and how much in
> close-to-the-metal C/C++. I really don't think you want a
> garbage-collected language for this, although I'm sure it's possible to
> use one if the heavy lifting is done in a low-level library.
All long-time processing (SVM, PCA) will be done I C using the
Accelerate framework (fast BLAS and LAPACK tuned for Inter
processors).

> Speaking of low-level libraries, since you're looking at BLAS, LAPACK,
> support vector machines, etc., you might want to install Atlas
> (Automatically Tuned Linear Algebra Subroutines). They just released
> 3.8.0 and it's hand tuned to most modern chips. On my dual-core Athlon64
> X2 2200+ I've gotten close to 10 GFLOPS on 32-bit operations!
I do not know if there is a difference between Accelerate framework
and Atlas. I might install Atlas if I can gain some speed here.

Thanks for the reply, it seems like Lua will be better for the
post-processing I need to do.

Gaspard