_mgcep.c

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/*
  ----------------------------------------------------------------
	Speech Signal Processing Toolkit (SPTK): version 3.0
			 SPTK Working Group

		   Department of Computer Science
		   Nagoya Institute of Technology
				and
    Interdisciplinary Graduate School of Science and Engineering
		   Tokyo Institute of Technology
		      Copyright (c) 1984-2000
			All Rights Reserved.

  Permission is hereby granted, free of charge, to use and
  distribute this software and its documentation without
  restriction, including without limitation the rights to use,
  copy, modify, merge, publish, distribute, sublicense, and/or
  sell copies of this work, and to permit persons to whom this
  work is furnished to do so, subject to the following conditions:

    1. The code must retain the above copyright notice, this list
       of conditions and the following disclaimer.

    2. Any modifications must be clearly marked as such.

  NAGOYA INSTITUTE OF TECHNOLOGY, TOKYO INSITITUTE OF TECHNOLOGY,
  SPTK WORKING GROUP, AND THE CONTRIBUTORS TO THIS WORK DISCLAIM
  ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL
  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO EVENT
  SHALL NAGOYA INSTITUTE OF TECHNOLOGY, TOKYO INSITITUTE OF
  TECHNOLOGY, SPTK WORKING GROUP, NOR THE CONTRIBUTORS BE LIABLE
  FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY
  DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
  WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
  ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
  PERFORMANCE OF THIS SOFTWARE.
 ----------------------------------------------------------------
*/

/****************************************************************

    $Id: _mgcep.c,v 1.2 2002/12/25 05:31:39 sako Exp $

    Mel-Generalized Cepstral Analysis

	int mgcep(xw, flng, b, m, a, g, itr1, itr2, dd, e);

	double   *xw  : input sequence
	int      flng : frame length
	double   *b   : coefficient b'(m)
	int      m    : order of mel cepstrum
	double   a    : alpha
	double   g    : gamma
	int      n    : order of recursions
	int      itr1 : minimum number of iteration
	int      itr2 : maximum number of iteration
	double   dd   : end condition
	double   e    : initial value for log-periodgram

	return value : 	0 -> completed by end condition
			-1-> completed by maximum iteration

*****************************************************************/

#include <stdio.h>
#include <SPTK.h>

double exp(), pow(), sqrt(), fabs();
double gain();

int mgcep(xw, flng, b, m, a, g, n, itr1, itr2, dd, e)
double *xw, *b, a, g, dd, e;
int flng, itr1, itr2, m, n;
{
    int    	  i, j, flag = 0;
    static double *x = NULL, *y, *d;
    static int    size_x, size_c;
    double 	  ep, epo, newton();
    
    if(x == NULL){
	x = dgetmem(flng+flng);
	y = x + flng;
	size_x = flng;
	
	d = dgetmem(m+1);
	size_c = m;
    }
    if(flng > size_x){
	free(x);
	x = dgetmem(flng+flng);
	y = x + flng;
	size_x = flng;
    }
    if(m > size_c){
	free(d);
	d = dgetmem(m+1);
	size_c = m;
    }
    
    movem(xw, x, sizeof(*x), flng);
    /*  periodegram  */
    fftr(x, y, flng);
    for(i=0; i<flng; i++)
	x[i] = x[i]*x[i] + y[i]*y[i] + e;

    /* initial value */    
    fillz(b, sizeof(*b), m+1);
    ep = newton(x, flng, b, m, a, -1.0, n, 0);

    if(g != -1.0){
	if (a != 0.0){
	    ignorm(b, b, m, -1.0);	/*  K, b'r(m)    -> br(m)         */
            b2mc(b, b, m, a);		/*  br(m)        -> c~r(m)        */
            gnorm(b, d, m, -1.0);	/*  c~r(m)       -> K~, c~'r(m)   */
	}
	else 
	    movem(b, d, sizeof(*b), m+1);

        gc2gc(d, m, -1.0, b, m, g);	/*  K~, c~'r(m)  -> K~, c~'r'(m)  */

	if (a != 0.0){
            ignorm(b, b, m, g);		/*  K~, c~'r'(m) -> c~r(m)        */
            mc2b(b, b, m, a);		/*  c~r(m)       -> br(m)         */
            gnorm(b, b, m, g);		/*  br(m)        -> K, b'r'(m)    */
	}
    }
    
    /*  Newton-Raphson method  */
    if(g != -1.0){
	for(j=1; j<=itr2; j++){
	    epo = ep;
	    ep = newton(x, flng, b, m, a, g, n, i);

	    if(j >= itr1)
		if (fabs((epo - ep)/ep) < dd){
		    flag = 1;
		    break;
		}
	}
    }

    if(flag) return(0);
    else     return(-1);
}

double newton(x, flng, c, m, a, g, n, j)
double *x, *c, a, g;
int flng, m, n, j;
{
    int		 i, m2;
    double 	 t, s, tr, ti, trr, tii, log();
    static double  *cr = NULL, *ci, *pr, *qr, *qi, *rr, *ri, *b;
    static int   size_cr, size_b;
    
    if(cr == NULL){
	cr = dgetmem(7*flng);
	ci = cr + flng;  pr = ci + flng;
	qr = pr + flng;  qi = qr + flng;
	rr = qi + flng;  ri = rr + flng;
	size_cr = flng;

	b = dgetmem(m+1);
	size_b = m;
    }
    if(flng > size_cr){
	free(cr);
	cr = dgetmem(7*flng);
	ci = cr + flng;  pr = ci + flng;
	qr = pr + flng;  qi = qr + flng;
	rr = qi + flng;  ri = rr + flng;
	size_cr = flng;
    }
    if(m > size_b){
	free(b);
	b = dgetmem(m+1);
	size_b = m;
    }

    m2 = m + m;
    
    fillz(cr, sizeof(*cr), flng);
    movem(&c[1], &cr[1], sizeof(*c), m);
    
    if (a != 0.0) 
	b2c(cr, m, cr, n, -a);
    
    fftr(cr, ci, flng);			/* cr +j ci : FFT[c]  */

    if (g == -1.0) 
	movem(x, pr, sizeof(*x), flng);
    else if (g == 0.0)
        for (i=0; i<flng; i++) 
	    pr[i] = x[i] / exp(cr[i] + cr[i]);
    else
        for (i=0; i<flng; i++){
            tr = 1 + g * cr[i]; ti = g * ci[i];
            s = (trr = tr * tr) + (tii = ti * ti);
            t = x[i] * pow(s, -1.0/g);
            pr[i] = (t /= s);
            rr[i] = tr * t; ri[i] = ti * t;
            t /= s; qr[i] = (trr - tii) * t;
	    s = tr * ti * t; qi[i] = s + s;
        }

    ifftr(pr, ci, flng);

    if (a != 0.0) 
	b2c(pr, n, pr, m2, a);
    
    if (g == 0.0 || g == -1.0){
        movem(pr, qr, sizeof(*pr), m2+1);
        movem(pr, rr, sizeof(*pr), m+1);
    }
    else{
       ifft(qr, qi, flng);
       ifft(rr, ri, flng);
       
       if (a != 0.0){
	   b2c(qr, n, qr, n, a);
	   b2c(rr, n, rr, m, a);
       }
   }

    if (a != 0.0){
	ptrans(pr, m, a);
	qtrans(qr, m, a);
    }

    /*  c[0] : gain, t : epsilon  */
    if (g != -1.0) 
	c[0] = sqrt(t = gain(rr, c, m, g));
    
    if (g == -1.0)
	fillz(qr, sizeof(*qr), m2+1);
    else if (g != 0.0) 
	for (i=2; i<=m2; i++) 
	    qr[i] *= 1.0 + g;
    
    if (theq(pr, &qr[2], &b[1], &rr[1], m, -1.)){
        fprintf(stderr, "mgcep : Error in theq() at %dth iteration !\n",j);
        exit(1);
    }

    for (i=1; i<=m; i++) c[i] += b[i];

    /*  c[0] : gain, t : epsilon  */
    if (g == -1.0) 
	c[0] = sqrt(t = gain(rr, c, m, g));
    
    return(log(t));
}

/*  gain(epsilon) calculation  */
double gain(er, c, m, g)
double *er, *c, g;
int m;
{
    register int i;
    double t;

    if (g != 0.0){
        for (t=0.0,i=1; i<=m; i++) t += er[i] * c[i];
        return(er[0] + g*t);
    }
    else return(er[0]);
    
}

/*  b'(m) to c(m)  */
b2c(b, m1, c, m2, a)
double *b, *c, a;
int m1, m2;
{
    register int        i, j;
    static double       *d = NULL, *g;
    static int          size;
    double 		k;
    
    if(d == NULL){
        size = m2;
        d = dgetmem(size+size+2);
        g = d + size + 1;
    }
    if(m2 > size){
        free(d);
        size = m2;
        d = dgetmem(size+size+2);
        g = d + size + 1;
    }

    k = 1 - a * a;

    fillz(g, sizeof(*g), m2 + 1);
    
    for (i = -m1; i <= 0; i++){
        d[0] = g[0];
	g[0] = b[-i];

        if (1 <= m2) 
	    g[1] = k * d[0] + a * (d[1] = g[1]);

        for (j = 2; j <= m2; j++)
            g[j] = d[j - 1] + a * ((d[j] = g[j]) - g[j - 1]);
    }
    movem(g, c, sizeof(*g), m2 + 1);
}

/*  recursion for p(m)  */
ptrans(p, m, a)
double *p, a;
register int m;
{
    double d, o;

    d = p[m];
    for (m--; m > 0; m--){ 
	o = p[m] + a * d;
	d = p[m]; p[m] = o;
    }
    o =  a * d; 
    p[m] = (1. - a * a) * p[m] + o + o;
}

/*  recursion for q(m)  */
qtrans(q, m, a)
double *q, a;
register int m;
{
    register int i;
    double d, o;

    m += m;
    i = 1; d = q[i];
    for (i++; i <= m; i++){ 
	o = q[i] + a * d;
	d = q[i]; q[i] = o;
    }
}