No one is answering you because your question does not make sense. a buffer~ represents audio that takes place in time, representing thousands of analysis frames, so it is 'realtime.' So no one knows what you want, and you'll have to state your problem more clearly.
FWIW, i have an external that calculates the FFT/iFFT offline. it takes data from a buffer, calculates magnitudes and phases (or simply real and imaginary parts) and puts those back into the buffer and vice versa. but it treats the buffer contents as one input frame and thus calculates one huge FFT out of it.
otherwise, if you need overlapping frames, i once did an object that calculates phase-vocoder data of buffer contents, i.e. frames of amplitude and frequency data offline, which is then copied into a separate buffer for later use in a real-time phase-vocoder patch.
the external is not ready for prime time, but if there is interest i could have a look what is missing.
then, i read a few days ago that someone (i think adam siska) is planing to make an object for offline FFT.
and of course there is jit.fft which works quite nice, albeit a little slower than external solutions.
@VB: Works for me now. Wow, the patch you made is perfect. I would have never ever thought that. Thank you so much. I've relied so much upon your work (starting with vb.cheby) I'm putting you in thank-you notes if I ever get to publish anything.
1. how can I change the colors of the curve (Like in iZotope R5)?
2. how can I change the maximum level of the curve at the end of the curve (frequence maximum should be 22050 Hz at the top of the window, now it's at the mid position)? (see picture attached...note, sound file is a sweep of 1 minute)
I have installed the Ircam mubu library and tested some patches...found nothing and everything seems uncomprensible. (and I hate also a little bit everything what comes from Ircam...two years ago I've buy a annual subscription to the Spat package, for 120€...now the price is raised to 140€...too much, and if you think that you have to pay this sum every year, with objects that you can't use for application that you've build also for other people..no, sorry, bye bye Ircam...)
And the patch from Volker is just perfect, does what I need execpt the color behaviour, so I need only to change his patch to get the colors, maybe only changein the main matrix from 1 plane to 4.