Composers desktop pro , convert to sine

gentleclockdivider

I am a big fan of cdp ( composers desktop pro ) inside renoise , it's an offline(non real time ) dsp powerhouse, the soundquality and the dsp algo's are amazing

There is this process which converts all the positive and negative cycles of an audio file into sine wave cycles during each zero crossing ( more often the cycle restarts before finishing it's full phase )

Have a look at the screenshots
Any idea how to implement this in core ( would it even be possible in primary ) ?

gentleclockdivider

Just thinking out loud here
We need a comparison with >0 and <0 which defines the positive and negative portion of the wave file .
If one of the statements is true , we take the sine funcion of a linear ramp.

Positive energy always starts at 0π rad , negative portionsalways start at

π radian

The most difficult part would be the frequency-duration of the ramp , which needs to be equal in length to the +/- duration of the cycle.

colB

You also need to scale each half sine…

Each time you get a zero crossing (with some hysteresis control maybe):

reset the peak value

reset the counter

for each tick:

update the counter; if the current amplitude is greater than peak, update peak; check for zero crossing

if there is one, store the count and the peak , and reset the process again…

=========================

It's interesting that the half sines mostly overshoot zero. This suggests that there is probably no interpolation in the zero crossing detection - which simplifies things.