examples\analysis\tracking\pitch-seventh.ck
//--
// name: pitch-seventh.ck
// desc: rough pitch tracking + dominant 7th
//
// author: Rebecca Fiebrink + Ge Wang
// date: 2007
//--


// analysis
adc => PoleZero dcblock => FFT fft => blackhole;
// synthesis
SinOsc s => JCRev r => dac;

// set reverb mix
.05 => r.mix;
// set to block DC
.99 => dcblock.blockZero;
// set FFT params
1024 => fft.size;
// window
Windowing.hamming( fft.size() ) => fft.window;

// interpolate
float target_freq, curr_freq, target_gain, curr_gain;
spork ~ ramp_stuff();

// go for it
while( true )
{
    // take fft
    fft.upchuck() @=> UAnaBlob blob;

    // find peak
    0 => float max; float where;
    for( int i; i < blob.fvals().size(); i++ )
    {
        // compare
        if( blob.fvals()[i] > max )
        {
            // save
            blob.fvals()[i] => max;
            i => where;
        }
    }

    // set freq
    (where / fft.size() * (second / samp)) * Math.pow(1.059,10) => target_freq;
    // set gain
    (max / .25) => target_gain;

    // hop
    (fft.size()/2)::samp => now;
}


// interpolation
fun void ramp_stuff()
{
    // mysterious 'slew'
    0.025 => float slew;

    // infinite time loop
    while( true )
    {
        (target_freq - curr_freq) * 5 * slew + curr_freq => curr_freq => s.freq;
        (target_gain - curr_gain) * slew + curr_gain => curr_gain => s.gain;
        0.0025::second => now;
    }
}
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