From: "Carlo E. Prelz" <fluido@...>
Date: 2013-02-27T16:48:22+09:00
Subject: Re: Does this specific sound library exist?

	Subject: Does this specific sound library exist?
	Date: Wed 27 Feb 13 07:58:01AM +0900

Quoting Dirk Vogel (lists@ruby-forum.com):

> after a week of research, I'm pretty convinced that for the project I'm
> planning Ruby might be a sensible choice. Let me explain: I programmed
> with Max/MSP for several years, but what I'm about to do right now goes
> beyond its limits. So I'm looking for another programming language. 

I have a couple of comments.

First, the "One UI to rule them all" wish is as close to utopia as it
can get. I can comment on Android (a good half of the mobile
platform): there, Java is the only way. It means that you can
certainly use Ruby (via Ruboto), but the UI is built up in its own
specific ways, quite hard to map to QT or Cocoa, or whatever
else. You'd have to have separate copies of the UI code for each
supported platform. Big work.

Second. I developed lots of audio/video code. I can tell you that,
while playing an audio file faster or slower is easy (you just skip
frames or play frames multiple times), it is much more expensive to
change pitch without changing length, or the reverse: you have to pass
each block of samples to Fourier transform, modify the resulting
spectrum, and reverse the transform. You need very good hardware to do
that live.

I add that the underlying audio layer of each platform is even more
diverging than the UI stuff. Linux uses ALSA, which does its work, but
is a royal PITA to work with. And you *need* to use a compiled
language (C), and a dedicated thread to manage the end feed to the
DSP. Any delay, even the smallest one, is perceived as unpleasant
clicks. 

You'll have to duplicate all this stuff for each platform, and you'll
need specific knowledge for each. There is no common library that I
know of. 

Good luck...!

Carlo

-- 
  *         Se la Strada e la sua Virtu' non fossero state messe da parte,
* K * Carlo E. Prelz - fluido@fluido.as             che bisogno ci sarebbe
  *               di parlare tanto di amore e di rettitudine? (Chuang-Tzu)