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Sample rate/Downsampling

Posted: Fri Sep 30, 2011 9:52 pm
by cuchufo
Hi,
Does anyone know how to work @ 8 KHz using ASIO drivers? is there an effective way to make a downsample? By using a hop it will only take 1 sample every certain number of samples and keep that value untill next hop, but the software will still process signals at the set sample rate.. i´ve been trying to use Tascam's asio drivers and asio4all drivers but none of them work at 8 KHz... same thing with my realtek soundcard..
Any idea???

Thanks

Re: Sample rate/Downsampling

Posted: Fri Sep 30, 2011 10:06 pm
by Morph
See the Sample Rate Selector and the Set Sample Rate Primitive.

Re: Sample rate/Downsampling

Posted: Wed Oct 05, 2011 9:54 pm
by cuchufo
Thanks for your answer!
but we´ve already tryed that... that´s how we´ve been simulating our system where everything works with internally generated signals and latency is not an issue(and the simulation rocks!)...

The problems arrive when we want to use acoustical signals captured by a pair of mics through the audio interface...
When we run the app/turn on audio output or input (@8KHz) we get a message saying the device does not support this sample rate... if we used a higher sampling freq. our filters should have much more coefficients and our software would get too slow...
we need to work with asio drivers and low fs.. any idea is welcome!!!

Thanks

Re: Sample rate/Downsampling

Posted: Thu Oct 06, 2011 10:39 am
by DSP
If your audio interface doesn't support 8Khz (most don't nowadays) then there is nothing to do in FlowStone. Most of my audio interfaces only support 44.1Khz or 22 Khz.

Maybe you could find some audio software that could do a Sample Rate Conversion (SRC) pre-FlowStone?

Re: Sample rate/Downsampling

Posted: Thu Oct 13, 2011 12:50 am
by cuchufo
I´m hoping my m-audio transit works... user guide says it works at 8 Khz... but it doesn´t specify if it does with asio drivers or with direct sound drivers... i hope i get it back soon to test it!!
thanks!