KVR Audio

ChewingAluminumFoil · Post by **ChewingAluminumFoil** » Thu Aug 21, 2014 1:17 pm

I used the single C file smbPitchShift.c from dspdimension.com in a VST. It required no changes at all and built 1st time and sounded good. It's WOL (wide open license).

I'm an FFT noob but if anyone wants to get their feet wet with FFT, this seems like it might be a good low-friction place to start.

http://www.denniscronin.net/dsp/vst.html

CAF

Xenakios · Post by **Xenakios** » Thu Aug 21, 2014 6:39 pm

Note that the smbpitchshift code will be completely broken if there are multiple instances of a VST plugin using the code. (Due to the static variables involved.)

foosnark · Post by **foosnark** » Thu Aug 21, 2014 8:41 pm

I don't think that's true. There's no mechanism for sharing that memory across different DLLs.

Big Tick · Post by **Big Tick** » Thu Aug 21, 2014 8:55 pm

Xenakios is right. The statics in smbPitchShift will be shared across instances of the same plugin.

foosnark · Post by **foosnark** » Fri Aug 22, 2014 6:03 pm

Huh, surprising. Good thing I tend to write in a more object-oriented way and wouldn't run into this, because I wouldn't have guessed.

lkjb · Post by **lkjb** » Sat Aug 23, 2014 8:09 am

I experimented a bit with smbPitchShift for PitchedDelay (also rewrote it into a class which isn't very hard) but I didn't pursue it any further as the code is rather slow and the pitching doesn't sound that good (at least if used in a feedback loop like in PitchedDelay).

I attached the code for the class but it also uses some JUCE classes (namely HeapBlock and ScopedPointer) and FFTReal for FFT. HeapBlock and ScopedPointer can be replaced with pointers and manual new/delete, FFTReal is available here.

ultra-simple FFT intro