LTFAT_EXTERN void
LTFAT_NAME(filterbankphasegrad)(const LTFAT_COMPLEX* c [],
const LTFAT_COMPLEX* ch[],
const LTFAT_COMPLEX* cd[],
const ltfatInt M,
const ltfatInt N[],
const ltfatInt L,
const LTFAT_REAL minlvl,
LTFAT_REAL* tgrad[],
LTFAT_REAL* fgrad[],
LTFAT_REAL* cs[])
{
#define FOREACHCOEF \
for(ltfatInt m=0;m<M;++m){\
for(ltfatInt ii=0;ii<N[m];++ii){
#define ARRAYEL(c) ((c)[m][ii])
#define ENDFOREACHCOEF }}
LTFAT_REAL minlvlAlt = LTFAT_COMPLEXH(cabs)(c[0][0]);
// Compute spectrogram from coefficients
// Keep max value
FOREACHCOEF
LTFAT_REAL en = LTFAT_COMPLEXH(cabs)(ARRAYEL(c))*LTFAT_COMPLEXH(cabs)(ARRAYEL(c));
ARRAYEL(cs) = en;
if(en>minlvlAlt)
minlvlAlt = en;
ENDFOREACHCOEF
// Adjust minlvl
minlvlAlt *= minlvl;
// Force spectrogram values less tha minLvlAlt to minlvlAlt
FOREACHCOEF
LTFAT_REAL csEl = ARRAYEL(cs);
if(csEl<minlvlAlt)
ARRAYEL(cs) = minlvlAlt;
ENDFOREACHCOEF
// Instantaneous frequency
FOREACHCOEF
LTFAT_REAL tgradEl = LTFAT_COMPLEXH(creal)(
ARRAYEL(cd)*LTFAT_COMPLEXH(conj)(ARRAYEL(c))/ARRAYEL(cs)
)/L*2;
ARRAYEL(tgrad) = fabs(tgradEl)<=2?tgradEl:0.0f;
ENDFOREACHCOEF
FOREACHCOEF
ARRAYEL(fgrad) = LTFAT_COMPLEXH(cimag)(
ARRAYEL(ch)*LTFAT_COMPLEXH(conj)(ARRAYEL(c))/ARRAYEL(cs)
);
ENDFOREACHCOEF
#undef FOREACHCOEF
#undef ENDFOREACHCOEF
#undef ARRAYEL
}
LTFAT_EXTERN void
LTFAT_NAME(pgauss_cmplx)(const ltfatInt L, const double w, const double c_t, const double c_f,
LTFAT_COMPLEX *g)
{
ltfatInt lr,k,nk;
double tmp,sqrtl, safe, gnorm;
sqrtl=sqrt((double)L);
safe=4;
gnorm=0;
/* Outside the interval [-safe,safe] then exp(-pi*x.^2) is numerically zero. */
nk=(ltfatInt)ceil(safe/sqrt((double)L/sqrt(w)));
for ( lr=0; lr<L; lr++)
{
//g[lr][0]=0.0;
//g[lr][1]=0.0;
g[lr] = (LTFAT_COMPLEX) 0.0;
for (k=-nk; k<=nk; k++)
{
/* Use a tmp variable to calculate squaring */
tmp = ((double)lr+c_t)/sqrtl-(double)k*sqrtl;
tmp = exp(-PI*tmp*tmp/w);
g[lr]+=tmp*LTFAT_COMPLEXH(cexp)(I*2*PI*c_f*((double)lr/L-(double)k));
}
double gReal = LTFAT_COMPLEXH(creal)(g[lr]);
double gImag = LTFAT_COMPLEXH(cimag)(g[lr]);
gnorm += (gReal*gReal+gImag*gImag);
}
/* Normalize it exactly. */
gnorm=sqrt(gnorm);
for ( lr=0; lr<L; lr++)
{
g[lr] /= gnorm;
}
}