I'm author of JamesDSP, a cross-platform(Windows, Linux, Android, 32 bit embedded) audio DSP that have 90% of Viper functionalities.
I had rewritten a fully functional VDC back in 2016.
VDC source code
My rewritten version is more robust than the original one, in principle, VDC is biquad cascade second order section(SOS).
For some strange reasons, I receive report said V4A don't support general SOS(I never actually use V4A, so that's what user report back to me to help me rewritten VDC), V4A only supports peaking biquad SOS, where JDSP VDC support all SOS just like Matlab filter() / filtfilt() function.
On top of that, JamesDSP VDC able to resample VDC by solving the biquad equation backward, see above link, as well as VDCToolbox I contribute to.
I'm author of JamesDSP, a cross-platform(Windows, Linux, Android, 32 bit embedded) audio DSP that have 90% of Viper functionalities.
I had rewritten a fully functional VDC back in 2016.
VDC source code
My rewritten version is more robust than the original one, in principle, VDC is biquad cascade second order section(SOS).
For some strange reasons, I receive report said V4A don't support general SOS(I never actually use V4A, so that's what user report back to me to help me rewritten VDC), V4A only supports peaking biquad SOS, where JDSP VDC support all SOS just like Matlab filter() / filtfilt() function.
On top of that, JamesDSP VDC able to resample VDC by solving the biquad equation backward, see above link, as well as VDCToolbox I contribute to.