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//SuperCollider is under GNU GPL version 3, http://supercollider.sourceforge.net/
//these extensions released under the same license
/*
* Meddis.cpp
*
* Created by Nick Collins on 10/06/2009.
* Copyright 2009 Nick Collins. All rights reserved.
*
*/
#include "MeddisHairCell.h"
#include <stdio.h>
//but see also
//A revised model of the inner-hair cell and auditory-nerve complex
//Christian J. Sumner, Enrique A. Lopez-Poveda, Lowel P. O'Mard, and Ray Meddis, J. Acoust. Soc. Am. 111, 2178 (2002), DOI:10.1121/1.1453451
//should be able to optimise a lot of these constants later on, ie g*dt or A+B
void MeddisHairCell::compute(float * input, float * output, int numsamples) {
int i;
//need to rescale amplitude to fit the example code p.1814; may need to push further, depends what is being taken as dB corresponding to full range -1 to 1
//10**(80/20-1.35) = 446.68359215096
//apparently 30 dB is RMS =1;
for (i=0; i<numsamples; ++i) {
float latest= input[i]* 446.68359215096; // * 100.0; //100 is additional gain...
//k is membrane permeability
if((latest+A) > 0.0)
k= g*dt*(latest+A)/(latest+A+B);
else k= 0;
float replenish= 0.0;
//if any store available, m is maximum
if (m>=q) replenish= y*dt*(m-q);
float eject= k*q;
float loss= l*dt*c;
float reuptake= r*dt*c;
float reprocess = x*dt*w;
q= q+replenish-eject+reprocess;
c= c+eject-loss-reuptake;
w= w+reuptake-reprocess;
//test for values over 0.02
//since hdt= 50000/44100.0 c is about 0.035 maximum,
//1.1337868*0.035 is about 0.04
////Meddis paper has a random number here; I prefer to keep deterministic? maybe a mistake, let's try it and see how it works out...
// if(i%10==0) printf("count %d testval %f \n",countsincelastfired, h*dt*c);
//
// if((countsincelastfired>firingdelay) && (h*dt*c>0.005)) {
//
// output[i]=20*c;
// countsincelastfired= 0;
// }else
// output[i]=0.0;
//
output[i]= 100.f*c; //h*c;
// if((countsincelastfired>firingdelay) && (h*c>0.5)) {
// //
// //c = 0.0; //c*0.5;
// //w=0.0;
// countsincelastfired= 0;
// }
//
// ++countsincelastfired;
}
}
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