[Jesse Chappell] >Tim Goetze wrote on Wed, 24-Mar-2004: > > > [Jesse Chappell] > > > >The stretch program was not properly clamping the output from > > >-1.0 -> 1.0 yielding to terrible cracks upon writing as 16bit > > >wave files when the output is clipped. The fact that non-clipping > > >(but very close to) input yielded clipping output is another issue, > > >but not crucial. > > > > > >I've attached a patch that fixes the problem. > > > > applied, thanks. > >I just realized that you may not want to clamp if your output >is a 32 bit float or double, as it is fully capable of handling >the value as produced. For instance, if (well, when) we suck this >algorithm into ardour we don't need to clamp, as our internal >format is float.
true. i'll make it an option. > > unfortunately, i can't come up with an algorithm giving the perfect > > scale factor for the stretching algorithm. ideas welcome, of course. > >Hmm, this is a tough one.... even soundtouch doesn't get it right, >and it doesn't have the same issues as the FFT approach.... maybe i'll come up with something when i find the time to really work with the phase vocoder, which will probably give a bunch of insights. too much to do right now to really dive into it (i feel that the pvoc package is just scratching the surface). tim
