/*----------------------------------------------------------------------------
* pst_ltp - harmonic postfilter
*----------------------------------------------------------------------------
*/
static void pst_ltpe(
int t0, /* input : pitch delay given by coder */
FLOAT *ptr_sig_in, /* input : postfilter input filter (residu2) */
FLOAT *ptr_sig_pst0, /* output: harmonic postfilter output */
int *vo, /* output: voicing decision 0 = uv, > 0 delay */
FLOAT gamma_harm /* input: harmonic postfilter coefficient */
)
{
/**** Declare variables */
int ltpdel, phase;
FLOAT num_gltp, den_gltp;
FLOAT num2_gltp, den2_gltp;
FLOAT gain_plt;
FLOAT y_up[SIZ_Y_UP];
FLOAT *ptr_y_up;
int off_yup;
/* Sub optimal delay search */
search_del(t0, ptr_sig_in, <pdel, &phase, &num_gltp, &den_gltp,
y_up, &off_yup);
*vo = ltpdel;
if(num_gltp == (F)0.) {
copy(ptr_sig_in, ptr_sig_pst0, L_SUBFR);
}
else {
if(phase == 0) {
ptr_y_up = ptr_sig_in - ltpdel;
}
else {
/* Filtering with long filter */
compute_ltp_l(ptr_sig_in, ltpdel, phase, ptr_sig_pst0,
&num2_gltp, &den2_gltp);
if(select_ltp(num_gltp, den_gltp, num2_gltp, den2_gltp) == 1){
/* select short filter */
ptr_y_up = y_up + ((phase-1) * L_SUBFRP1 + off_yup);
}
else {
/* select long filter */
num_gltp = num2_gltp;
den_gltp = den2_gltp;
ptr_y_up = ptr_sig_pst0;
}
}
if(num_gltp >= den_gltp) {
/* beta bounded to 1 */
if (gamma_harm == GAMMA_HARM) gain_plt = MIN_GPLT;
else gain_plt = (F)1./((F)1.+ gamma_harm);
}
else {
gain_plt = den_gltp / (den_gltp + gamma_harm * num_gltp);
}
/** filtering by H0(z) = harmonic filter **/
filt_plt(ptr_sig_in, ptr_y_up, ptr_sig_pst0, gain_plt);
}
return;
}
/*----------------------------------------------------------------------------
* pst_ltp - harmonic postfilter
*----------------------------------------------------------------------------
*/
static void pst_ltp(
Word16 t0, /* input : pitch delay given by coder */
Word16 *ptr_sig_in, /* input : postfilter input filter (residu2) */
Word16 *ptr_sig_pst0, /* output: harmonic postfilter output */
Word16 *vo /* output: voicing decision 0 = uv, > 0 delay */
)
{
/**** Declare variables */
int i;
Word16 temp;
Word16 ltpdel, phase;
Word16 num_gltp, den_gltp;
Word16 num2_gltp, den2_gltp;
Word16 sh_num, sh_den;
Word16 sh_num2, sh_den2;
Word16 gain_plt;
Word16 y_up[SIZ_Y_UP];
Word16 *ptr_y_up;
Word16 off_yup;
Word16 *ptr_sig;
Word16 sig_cadr[SIZ_RES2], *ptr_sig_cadr;
Word16 nb_sh_sig;
Word32 L_temp;
/* input signal justified on 13 bits */
ptr_sig = ptr_sig_in - MEM_RES2;
temp = 0;
for(i=0; i<SIZ_RES2; i++) {
temp |= abs_s(ptr_sig[i]);
}
nb_sh_sig = sub(3, norm_s(temp));
for(i=0; i<SIZ_RES2; i++) { /* nb_sh_sig may be >0, <0 or =0 */
sig_cadr[i] = shr( ptr_sig[i], nb_sh_sig);
}
ptr_sig_cadr = sig_cadr + MEM_RES2;
/* Sub optimal delay search */
search_del(t0, ptr_sig_cadr, <pdel, &phase, &num_gltp, &den_gltp,
&sh_num, &sh_den, y_up, &off_yup);
*vo = ltpdel;
if(num_gltp == 0) {
Copy(ptr_sig_in, ptr_sig_pst0, L_SUBFR);
}
else {
if(phase == 0) {
ptr_y_up = ptr_sig_in - ltpdel;
}
else {
/* Filtering with long filter */
compute_ltp_l(ptr_sig_cadr, ltpdel, phase, ptr_sig_pst0,
&num2_gltp, &den2_gltp, &sh_num2, &sh_den2);
if(select_ltp(num_gltp, den_gltp, sh_num, sh_den,
num2_gltp, den2_gltp, sh_num2, sh_den2) == 1) {
/* select short filter */
temp = sub(phase, 1);
L_temp = L_mult(temp, L_SUBFRP1);
L_temp = L_shr(L_temp, 1);
temp = extract_l(L_temp);
temp = add(temp, off_yup);
/* ptr_y_up = y_up + (phase-1) * L_SUBFRP1 + off_yup */
ptr_y_up = y_up + temp;
}
else {
/* select long filter */
num_gltp = num2_gltp;
den_gltp = den2_gltp;
sh_num = sh_num2;
sh_den = sh_den2;
ptr_y_up = ptr_sig_pst0;
}
/* rescale y_up */
for(i=0; i<L_SUBFR; i++) { /* nb_sh_sig may be >0, <0 or =0 */
ptr_y_up[i] = shl(ptr_y_up[i], nb_sh_sig);
}
}
temp = sub(sh_num,sh_den);
if(temp >= 0) den_gltp = shr(den_gltp, temp);
else {
num_gltp = shl(num_gltp, temp); /* >> (-temp) */
}
if(sub(num_gltp ,den_gltp)>=0) {
/* beta bounded to 1 */
gain_plt = MIN_GPLT;
}
else {
/* GAMMA_G = 0.5 */
/* gain_plt = den_gltp x 2**15 / (den_gltp + 0.5 num_gltp) */
/* shift 1 bit to avoid overflows in add */
num_gltp = shr(num_gltp, 2);
den_gltp = shr(den_gltp, 1);
temp = add(den_gltp, num_gltp);
gain_plt = div_s(den_gltp, temp); /* Q15 */
}
/** filtering by H0(z) = harmonic filter **/
filt_plt(ptr_sig_in, ptr_y_up, ptr_sig_pst0, gain_plt);
}
return;
}