FFT with Filestream slow

[jerry]

FFT (DShow9) is slow when used with FileStream meaning it outputs data less frequent compared to using it with AudioIn. Also, BuffersPerFrame on FFT is down to 0.07 with FileStream and up to 0.7 with AudioIn.

Why is that? Is there a way to make FFT output data more frequently?

Thanks a lot!

[tonfilm]

hi jerry, i think this is related to the buffer size of your audio output. use VVVV.Audio have control over such thing from withing vvvv. otherwise you could try to change your system settings.

[motzi]

if i remember correctly, the buffer size behaviour also depends on the audio file format you are using. maybe try converting your files to uncompressed waves and see if this changes something.

tonfilms suggestion to move to VVVV.Audio is the more modern way to go though…

[jerry]

Thanks, everyone.

I’ve been using uncompressed WAV from the start. I’ve now given VAudio a try, and it seems to be working better. Changing the buffer size doesn’t seem to make a difference though, but changing the sample rate does.

For other reasons, I had to shift this part to an app based on Processing using the beads library and feeding the data to vvvv via OSC now. I can see similar issues there as well. Will have to investigate this more.

Thanks again.

[jerry]

A friend just told me this has to do with the window size of FFT.
Both FFT implementations of vvvv don’t have a pins for window size though.