PV_BinDelay Delay and Feedback on a bin by bin basis

PV_BinDelay(buffer, maxdelay, delaybuf, fbbuf, hop = 0.5)

buffer - the FFT buffer.

maxdelay - in seconds. Used at init time to create memory for the delays. Non-modulatable.

delaybuf - a buffer of (fft buffer size / 2) containing the delay times for each bin. Delay times

will be rounded to the closest bin. Smaller FFT windows will yield better time resolution.

fbbuf - a buffer of (fft buffer size / 2) containing the fb percentages for each bin.

hop - if you are using FFT with a hop value different then the default 0.5, you need to tell PV_BinDelay

so it can calculate the correct times.

WARNING! This UGen needs to allocate a large amount of real-time memory at the outset (approx.

SampleRate * maxDelayTime). This will cause a CPU spike at startup. Also, due to memory

mangement restrictions, There is a limited number of previous frames that can be stored. Right now

no more the 512 frames can be stored. With a frame size of 512 samples, this makes a hard limit

to the max delay of about 5.9 seconds at a SR of 44100 (or (FFT size * 512) / SR). Chances are,

however, that you will run out of RT memory (the memSize ServerOption) before hitting these

limits, especially at larger FFT frame sizes.

Examples:

s.boot;

(

Routine.run({

// use as multislider - del time vals on top, feedback on the bottom

// max delay time is 1 second, delaytime and fb are initialized to 0.0

// and are controlled by the GUI. The multi-slider on the top controls

// each bins delay time, the bottom controls FB.

var size, awin, bsl, car, dar, fsl, maxdel, synth, cond;

size = 128;

maxdel = 0.5;

cond = Condition.new;

s.sendMsg(\b_alloc, b=s.bufferAllocator.alloc(1), size * 2);

s.sendMsg(\b_alloc, c=s.bufferAllocator.alloc(1), size);

s.sendMsg(\b_alloc, d=s.bufferAllocator.alloc(1), size);

y = Array.fill(size, {0.0});

s.sendBundle(0.1, [\b_setn, d, 0, size] ++ y);

z = Array.fill(size, {arg i; 0.0});

s.sendBundle(0.1, [\b_setn, c, 0, size] ++ z);

s.sync(cond);

synth = SynthDef("help-noopFFT", { arg inbus,out=0,bufnum=0, dels=0, fb=0;

var in, chain;

in = Impulse.ar(0.33);

in = PlayBuf.ar(1, playbuf, loop: 1);

chain = FFT(bufnum, in, 0.25);

chain = PV_BinDelay(chain, maxdel, dels, fb, 0.25);

Out.ar(out,

in + IFFT(chain) // inverse FFT

);

}).play(s,[\out,0,\bufnum,b,\dels, c, \fb, d, \inbus, s.options.numOutputBusChannels]);

{

awin = GUI.window.new("test", Rect(200 , 450, 10 + (size * 1), 10 + (size * 2)));

awin.view.decorator = FlowLayout(awin.view.bounds);

bsl = GUI.multiSliderView.new(awin, Rect(0, 0, size * 1, size * 1));

bsl.action = {arg xb; ("Deltime index: " ++ xb.index ++" value: " ++

(xb.currentvalue * maxdel)).postln;

s.sendMsg(\b_set, c, xb.index, xb.currentvalue * maxdel);

};

fsl = GUI.multiSliderView.new(awin, Rect(0, 0, size * 1, size * 1));

fsl.action = {arg xb; ("FB index: " ++ xb.index ++" value: " ++ xb.currentvalue).postln;

s.sendMsg(\b_set, d, xb.index, xb.currentvalue);

};

car = Array.new;

size.do({arg i;

car = car.add(0);

});

bsl.value_(car);

dar = Array.new;

size.do({arg i;

dar = dar.add(0);

});

fsl.value_(car);

bsl.xOffset_(5);

bsl.thumbSize_(12.0);

fsl.xOffset_(5);

fsl.thumbSize_(12.0);

// value axis size of each blip in pixels

bsl.valueThumbSize_(15.0);

// index axis size of each blip in pixels

bsl.indexThumbSize_( bsl.bounds.width / car.size );

bsl.gap = 0;

// value axis size of each blip in pixels

fsl.valueThumbSize_(15.0);

// index axis size of each blip in pixels

fsl.indexThumbSize_( fsl.bounds.width / dar.size );

fsl.gap = 0;

awin.front;

awin.onClose_({

synth.free;

s.sendMsg(\b_free, b);

s.sendMsg(\b_free, c);

s.sendMsg(\b_free, d);

})

}.defer;

})

)