Haven’t put this in xrnx discussion because, as far as I know, Renoise can’t add markers to samples and I wouldn’t quite rely on peak-detection alone even if I thought it was worth trying to tackle with LUA.
Take a sample and from it calculate a list of BPM changes that would cause the beat lines in Renoise to coincide with the actual hits.
Using Markers, either inserted by hand in a wave editor or automatically by a transient detection program calculate the BPM required to have each group of lines in Renoise.
You can not enter fractional BPM values with the Pattern Commands and Renoise does not allow setting of BPM via Automation Curves. (Possibly the bigger one.)
You may wish to mark beats of different length. - Solution = to add a ballpark figure for BPM which Renoise will always try and stay around. This would also be needed for those that like to Track at double BPM (although again Pattern Commands don’t give access to high enough numbers.)
So it seems the biggest barrier at the moment is BPM changes only being accessable from Pattern commands. Plus of course the coding capabilities but I honestly don’t think it can be hard to read number of samples between markers, read sample rate, calculate length of section and thus the required BPM of the section.
Or is it just a stupid idea anyway!?
(Brainwave inspired by Cee Tama’s thread on beatmapping.)