Speed requirements timestretcher

I’m currently optimizing my timestretcher. Just to give an idea of the speed we need to achieve: with a windowsize of 4096 samples and an overlap of 16 frames. We have about 5.8 milliseconds between frame calculations. Now, this is stereo which means that we only have 2.9 milliseconds/frame. In each frame we have to detect sine waves, extract them relocate them to other positions. Typically we have around ~600 peaks per frame. That leaves us about 4.8 microseconds per peak. Each peak must be detected, extracted, repositioned, resampled and added to the final frame again. Currently I manage to do this in 13 microseconds. And now the push is on. Can we speed this further up with a factor 2.7 ?

Leave a Reply

Your email address will not be published. Required fields are marked *