[linux-audio-user] Animatronic parrot solution?

[Robert Jonsson]

Saturday 16 August 2003 16:59 skrev Daniel James:
> Hello all,
>
> I've been asked by an animatronics technician for suggestions as how
> they might go about solving a particular problem with a robot parrot
> at a local theme park.

Oh, nice, I went to a zoo with my children once, they had a parrot just like 
that, they thought it was immensely funny :).
>
> The robot's voice feature was designed around a PC/Windows platform
> using Cool Edit Pro and scripted in Visual Basic. The idea is that
> you say something to the parrot, it pitch shifts your voice then
> repeats what you said two seconds later. If no-one talks to the
> parrot for a while, it says "hello, my name is Sancho, talk to me".
> Needless to say, they are having severe reliability problems with
> Windows as it is being used day in, day out.
>
> Can anyone suggest a suitable Linux solution for this parrot? I was
> thinking about ecasound combined with a pitch shift plugin, if one
> exists. If the solution could run entirely in RAM (CD booting,
> perhaps?) then that would solve the problem of hard disk reliability.

Any of the shelf distro would probably suffice. For reliability I would 
propose using a Flash disk. fast, small, clean, reliable, inexpensive. 
There are heaps of small, cheap motherboards these days that have built in 
sound so that won't be a problem.

As for solutions to the actual problem...
I'm not entirely sure... 
You'd want to 'sniff' the data continuously at the same time as you loop it 
around and pitchshift it to the output...

It would probably be easiest to do a small c program which utilized some 
ladspa plugins for the pitchshift, probably noise gate and, possibly the 
delay.

I'm having a hard time figuring out how to do it with off the shelf tools 
though, since it involves doing several things in parallell.. .

But there is probably some obvious way that I'm ignoring :)

Btw, It's always nice with real life applications of open source tools!

/Robert