[Speex-dev] echo cancellation on PDA

Nicholas Xu
2006-11-02T11:45:59Z

2006/11/2, Jean-Marc Valin
<jean-marc.valin@usherbrooke.ca>:
> > Today I tried speex echo cancellation on my VoIP application running
> > on a windows mobile based PDA (OMAP1510 168MHz). The result is
> > disappointing: it takes 150-250 ms to do echo cancellation (by calling
> > speex_echo_capture() ) for a 20 ms frame!
>
> Are you by any chance using an insane sampling rate and/or tail length.
> Try a sampling rate of 8000 Hz, 128-sample frame size and 1028-sample
> tail length.
In my appliation, the sampling rate is 8000 Hz, and time stamp is
20ms, doesn't it mean I should initialize echo_state like
speex_echo_init_state(160,n*160)?
>
> > I've defined the FIXED_POINT macro. Is there anyway to do some
> > optimization?
>
> Probably. With the params above, the AEC should be able to run in
> real-time on an ARM CPU.
>
>        Jean-Marc
>
>