Re: 'circular' use of loop devices?

Hi,

On Sat, 14 Apr 2012, James Mckernon wrote:

> I'm trying to experiment with some experimental effects paths within 
> ecasound - in particular, ones that involve 'circular' chains, whose 
> input and output are the same loop device. I'm thinking something along 
> the lines of the following:
> 
> ecasound -a:1 -i:input.mp3 -o:loop,1 -a:2 -i:loop,1 -o:alsa -a:3 -i:loop,1 [some_effects_here] -o:loop,1

When ecasound processes this, when it reaches "-a:3 -i:loop,1", it 
connects "loop,1" only to chain 3 and not anymore to 1, and this causes 
the error messages below (no input for chain 1).

So when you want to connect an input/output to multiple chains, you have 
to do it like this:

  ecasound -a:1 -i input.mp3 -a:1,3 -o:loop,1 -a:2,3 -i:loop,1 -a:2 -o:alsa -a:3 [some_effects_here]

But this is probably not quite what you are looking for, as each hop from 
a loop output to its input, causes an additional delay of one engine 
iteration (equivalent to -b:size, e.g. -b:1024@44100Hz -> delay of 
~23.2ms). You can modify the delay by setting -b:xxx to different values, 
but this is a bit clumsy and may have side-effects to e.g. overall 
performance (low buffersize values increase engine overhead).

> Funnily enough, the closely related setup,
> ecasound -a:1 -i:input.mp3 -o:loop,1 -a:2 -i:loop,1 -o:alsa -a:3 -i:loop,2 [some_effects_here] -o:loop,2
> seems to instantiate without any problems.

Yep, so here "loop,1" and "loop,2" are considered separate objects, so the 
above error doesn't happen (each chain has an input and an output defined 
above).

------------------------------------------------------------------------------
For Developers, A Lot Can Happen In A Second.
Boundary is the first to Know...and Tell You.
Monitor Your Applications in Ultra-Fine Resolution. Try it FREE!
http://p.sf.net/sfu/Boundary-d2dvs2
_______________________________________________
Ecasound-list mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/ecasound-list