[linux-audio-dev] jack_process and pitch-shifting

[Olivier Guilyardi]

Erik de Castro Lopo wrote:

>On Fri, 22 Apr 2005 16:48:32 +0100
>Steve Harris <S.W.Harris at ecs.soton.ac.uk> wrote:
>
>  
>
>>Doing heavy jobs in the process() callback is fine, as long as the CPU
>>load is deterministic. I this case I think it should be.
>>    
>>
>
>Yep, the CPU load of the sample rate conversion process of libsamplerate 
>is pretty close to linearly related to the size of the blocks you are
>converting.
>  
>
I want to vary the pitch in realtime, and even to totally enable/disable 
the pitch-shifting routines when needed, always in realtime, while rolling.

I'm not sure if all that's still linear. The CPU load of my process() 
callback may remain constant when the user vary the pitch, but it will 
suddenly increase/decrease if the user enables/disables pitch-shifting.

Is this still deterministic/linear ? If not, is spanning a new thread 
the only alternative ?

--
  og