[Fluxus] Output of 'gh'

[Dave Griffiths]

Hi all,

Yes, this seems to be a terminology bug - I don't really have an audio
or dsp background. fwiw the audio analysis could do with some looking
at, there are lots of quite easy ways it could be improved eg. 

* a configurable number of bands
* a way of specifying frequency directly and some gaussian falloff to
tune in on particular instruments
* beat detection
* ...

cheers,

dave

On Fri, 2009-05-22 at 10:46 -0700, Scott wrote:
> I think the name Harmonic is what's confusing. My understanding is
> that it's just a "frequency band".
> 
> That said - it might be cool to support some alternate ways of binning
> the fft data.
> 
> On Fri, May 22, 2009 at 2:30 AM, Janosch Peters <petersj at in.tum.de> wrote:
> > Hi Gabor,
> >
> >> fluxus sums up the results of the fft calculation in 16 fft
> >> bins. as far as i know, it calculates the fft for the buffer size you
> >> specify in start-audio, then sums up the neighbouring values
> > according
> >> to a non-linear mapping table, which specifies for example that the
> >> 9thharmonic will be calculated by summing up the bands between 28 and
> >> 40.
> >
> > Ok so that means we have a fixed relation between frequencies and
> > harmonics, e.g. a sine pitch of 440hz will always be assigned to the
> > very same harmonic. So it might look like this:
> >
> > frequency(-band)        harmonic
> > 25...50...75        0
> > 50...100..150       1
> > 100..200..300       2
> >
> > Here the fundamental frequency is 50hz. I guess frequencies far away
> > from the frequency band center are weighted less?
> >
> > I recognized that "centering" frequencies within their frequency band
> > would mean that the frequncie bands are overlapping, correct?
> >
> > And whats the purpose of assigning multiple frequncie bands to one
> > harmonic? Wouldnt be a 1:1 relation ship (as in the example) enough?
> >
> > Sorry for asking so many questions, but Im going to give a presentation
> > about fluxus, and I'd like to know a bit what Im talking about. :-)
> >
> > cheers,
> > Janosch
> >
> > --
> > I'm trying a new usenet client for Mac, Nemo OS X, since 0 days.
> > You can download it at http://www.malcom-mac.com/nemo
> >
> >