PV_MagBuffer Store FFT data in another buffer for other use

PV_FreqBuffer


PV_MagBuffer(buffer, databuffer)

PV_FreqBuffer(buffer, databuffer)


databuffer - a buffer of (fft buffer size / 2) for storing freq or mag data in

Examples:


// stores the Mag values from an FFT analysis into a buffer to be used outside the FFT process

(

SynthDef(\magbufferana, {arg fftbuf, sndbuf, magbuf, freqbuf;

var in, chain;

in = PlayBuf.ar(1, sndbuf, BufRateScale.kr(sndbuf), loop: 1);

chain = FFT(fftbuf, in);

chain = PV_MagBuffer(chain, magbuf);

chain = PV_FreqBuffer(chain, freqbuf);

IFFT(chain);

}).load(s);

SynthDef(\magbuffersynth, {arg gate = 1, magbuf, freqbuf, fftframes, scale = 1;

var pars, src, out, trig, env;

env = EnvGen.kr(Env([0, 1, 0], [1, 1], \sin, 1), gate, doneAction: 2);

// we'll grab 50 random partials

pars = Array.fill(50, {IRand.new(5, fftframes)});

// use PinkNoise as a filter src

src = PinkNoise.ar(0.5);

// Index the freq and mag buffers to control a filter bank

out = (BPF.ar(src, Index.kr(freqbuf, pars), 0.001) * Index.kr(magbuf, pars)).sum * scale;

Out.ar(0, out * env);

}).load(s);

)

s.boot;


// allocate the fft buf, sndbuf, and mag and freq bufs

(

s.sendBundle(0.1, [\b_alloc, 0, 1024], [\b_allocRead, 1, "sounds/a11wlk01.wav"], [\b_alloc, 2, 512], 

[\b_alloc, 3, 512]);

)

// start the analuysis

(

s.sendMsg(\s_new, \magbufferana, z = s.nextNodeID, 0, 1, \fftbuf, 0, \sndbuf, 1,

\magbuf, 2, \freqbuf, 3);

)

(

// there is a strange buildup of energy when a note starts... so, start the synthesis a bit later

s.sendMsg(\s_new, \magbuffersynth, y = s.nextNodeID, 1, 1, \magbuf, 2, \freqbuf, 3, 

\fftframes, 512);

)

( // kill the current note, start a new one (with different pars)

s.sendMsg(\n_set, y, \gate, 0);

s.sendMsg(\s_new, \magbuffersynth, y = s.nextNodeID, 1, 1, \magbuf, 2, \freqbuf, 3, 

\fftframes, 512)

)

// free the synthesis synth

s.sendMsg(\n_set, y, \gate, 0)

// free the analysis

s.sendMsg(\n_free, z);


// free the buffers

4.do{arg i; s.sendMsg(\b_free, i)};


s.quit