// Music 220a - Final Project - Romain Michon
// 12/11/2012
// This is an 'extended' karplus strong algorithm. It is excited by the signal from the audio input. Sorry for the comments in french :). The important one are in English...

declare name "ksRom";

import("music.lib"); // defini noise, SR et delay
import("instrument.lib");

// GUI
freq = hslider("freq", 328, 20, 20000, 1); // Hz 
gain = hslider("gain", 1, 0, 20, 0.01); // gain compris entre 0 et 1
att = hslider("att",0.1,0,1,0.01);
bdwth = hslider("fBandwidth",50,0,10000,0.1);

stringFilter(x) = rho * ((b0 * x) + (b1 * x'))
with{
	B = hslider("brightness", 0.5, 0, 1, 0.01);
	t60 = hslider("decaytime", 4, 0, 10, 0.01);
	rho = pow(0.001,1.0/(freq*t60));
	b1 = 0.5*B; b0 = 1.0-b1;
};

P = SR/freq : smooth(0.999); 
resonator = (+ : fdelay(4096, P)) ~ (stringFilter);

// very simple pitch shifter
transpose (w, x, s, sig)  =
fdelay1s(d,sig)*fmin(d/x,1) + fdelay1s(d+w,sig)*(1-fmin(d/x,1))
   	with {
		i = s;
		d = i : (+ : +(w) : fmod(_,w)) ~ _;
        };

// shift the pitch of the input signal in function of the desired frequency. 164 is the resonance frequency of the CD
shift = (164/(freq)) - 1;

// GUI for the pitch shifter
pitchshifter = transpose(
	hslider("window", 1000, 50, 10000, 1),
	hslider("xfade", 10, 1, 10000, 1),
	shift
);

process = *(gain) : lowpass(2,bdwth) : pitchshifter : resonator;