Hi, I'm giving an hand for a project that intend to transform fingerprints to an image processed by animating the points found by libfprint with the audio analysis of the print's owner voice.

Each point animation is rotating by a speed defined with amplitude of the frequency where near the center is the lowest freq and the perimeter is the highest.

That part was relatively easy to make, it's just a matter of computing the sum of all magnitudes for each frequency range, with using fft, filling a table with all magnitudes and summing all the values, and after, making an interpolation with the current magnitude, at each block, giving the new z angular reference to a Gem object that is rendering on a simple buffered gemwin and capture an image.

Sampling rate have to be set to 48khz to get an integer number of blocks, for an image rate of 24i/s... (48000/24=2000 samples)

Now I'd like to get the frequency range of the voice signal, before making the magnitude analysis, to not get 'dead frequencies' in the animation.

Also the point's radius will have to change following the current deviation from the mean frequency for the analyzed range.

I've attached an archive with patches I've made for processing the animation.

So my question is in the title, how could I get the mean frequency of the whole signal, and from each frequency range?

That question won't come alone, I'm using Gem for processing the image because I know it well enough, but the rendering isn't really amazing. Each image are written in the hard drive with [pix_write] with [file img/myimage 100(, and I'm never sure about how pix_write will find the img/ folder that is into the same folder than the main patch, and the best quality of a rendered jpg image is really dirty. I'd like to use tiff images instead but I haven't found a CLI yet for building the video with, mencoder can only handle the jpeg from pix_write. Also the [pix_snap]--[pix_record] solution is not stable and compatible enough for this installation. Sorry to be out of topic but anyone knows a program I could handle in a script that builds videos from tiff images?

And finally, does anyone know another solution for procesing the image, with other pd externals, or external programs we can handle from pd?

Thanks.