RE: [linux-audio-user] Acid for Linux ? - Pitch shift

Just some ideas for you... Actually, the pitch modification part is handled quite nicely here in Linuxland by freqtweak. However, to date freqtweak is pretty static in terms of how it manipulates frequency over time. Acid has the ability to shift samples by known amounts, so that if I have a bass line in C, I can shift it up a major 4th to F and it will fit into the sound quite easily. This function in Acid works pretty well over a limited range, say +/- a major 6th, but starts to fall apart pretty badly at an octave, in my experience. (It depends a lot on the library.) Until this morning I hadn't considered using freqtweak to accomplish the same thing. Today I would have to take an input wave file for the base line, then shift it appropriately and write it back to disk as a separate wave file, using more disk space and creating more problems at the app level dealing with yet another wave file to be read and played back. Maybe a future development might be freqtweak itself, but: 1) Modified to be a ladspa plugin 2) Modified to have some built in mechanism to step the frequencies up and down by known amounts 3) Having a way to call those frequency changes through an API Some sort of feature set in this general space would go a long way towards accomplishing what you can do today with pitch manipulation in Acid. Just some ideas for you... -----Original Message----- From: linux-audio-user-admin(a)music.columbia.edu [mailto:linux-audio-user-admin@music.columbia.edu]On Behalf Of Brian Redfern Sent: Tuesday, December 10, 2002 10:53 AM To: linux-audio-user(a)music.columbia.edu Subject: RE: [linux-audio-user] Acid for Linux ? Well, with ladspa one could always make a tempo edit plugin, which would allow one to change the tempo of a sound file that's had the ladspa effect applied. I'm not good enough at c/c++ yet to do that, but ladspa seems to be pretty wide open in terms of the types of effects that could be created. I would think that the functionality in Recyle could be cloned in a ladspa plugin, that way many diverse systems could use the plugin without having to change the UI, as the Acid functionality with "painting in audio" is more of a convenience, the real functionality is its ability to match tempo and pitch of disparate samples. Its really just a time shifting effect that changes tempo without changing pitch. http://www.brianredfern.org On Mon, 9 Dec 2002, Mark Knecht wrote: choose