/** Finds the best quantized 3-tap pitch predictor by analysis by synthesis */
int pitch_search_3tap(
spx_word16_t target[], /* Target vector */
spx_word16_t* sw,
spx_coef_t ak[], /* LPCs for this subframe */
spx_coef_t awk1[], /* Weighted LPCs #1 for this subframe */
spx_coef_t awk2[], /* Weighted LPCs #2 for this subframe */
spx_sig_t exc[], /* Excitation */
const void* par,
int start, /* Smallest pitch value allowed */
int end, /* Largest pitch value allowed */
spx_word16_t pitch_coef, /* Voicing (pitch) coefficient */
int p, /* Number of LPC coeffs */
int nsf, /* Number of samples in subframe */
SpeexBits* bits,
char* stack,
spx_word16_t* exc2,
spx_word16_t* r,
int complexity,
int cdbk_offset,
int plc_tuning,
spx_word32_t* cumul_gain
) {
int i;
int cdbk_index, pitch = 0, best_gain_index = 0;
VARDECL(spx_sig_t * best_exc);
VARDECL(spx_word16_t * new_target);
VARDECL(spx_word16_t * best_target);
int best_pitch = 0;
spx_word32_t err, best_err = -1;
int N;
const ltp_params* params;
const signed char* gain_cdbk;
int gain_cdbk_size;
int scaledown = 0;
VARDECL(int * nbest);
params = (const ltp_params*) par;
gain_cdbk_size = 1 << params->gain_bits;
gain_cdbk = params->gain_cdbk + 4 * gain_cdbk_size * cdbk_offset;
N = complexity;
if (N > 10)
N = 10;
if (N < 1)
N = 1;
ALLOC(nbest, N, int);
params = (const ltp_params*) par;
if (end < start) {
speex_bits_pack(bits, 0, params->pitch_bits);
speex_bits_pack(bits, 0, params->gain_bits);
SPEEX_MEMSET(exc, 0, nsf);
return start;
}
#ifdef FIXED_POINT
/* Check if we need to scale everything down in the pitch search to avoid overflows */
for (i = 0; i < nsf; i++) {
if (ABS16(target[i]) > 16383) {
scaledown = 1;
break;
}
}
for (i = -end; i < nsf; i++) {
if (ABS16(exc2[i]) > 16383) {
scaledown = 1;
break;
}
}
#endif
if (N > end - start + 1)
N = end - start + 1;
if (end != start)
open_loop_nbest_pitch(sw, start, end, nsf, nbest, NULL, N, stack);
else
nbest[0] = start;
ALLOC(best_exc, nsf, spx_sig_t);
ALLOC(new_target, nsf, spx_word16_t);
ALLOC(best_target, nsf, spx_word16_t);
for (i = 0; i < N; i++) {
pitch = nbest[i];
SPEEX_MEMSET(exc, 0, nsf);
err = pitch_gain_search_3tap(target, ak, awk1, awk2, exc, gain_cdbk, gain_cdbk_size, pitch, p, nsf,
bits, stack, exc2, r, new_target, &cdbk_index, plc_tuning, *cumul_gain, scaledown);
if (err < best_err || best_err < 0) {
SPEEX_COPY(best_exc, exc, nsf);
SPEEX_COPY(best_target, new_target, nsf);
best_err = err;
best_pitch = pitch;
best_gain_index = cdbk_index;
}
}
/*printf ("pitch: %d %d\n", best_pitch, best_gain_index);*/
speex_bits_pack(bits, best_pitch - start, params->pitch_bits);
speex_bits_pack(bits, best_gain_index, params->gain_bits);
#ifdef FIXED_POINT
*cumul_gain = MULT16_32_Q13(SHL16(params->gain_cdbk[4 * best_gain_index + 3], 8), MAX32(1024, *cumul_gain));
#else
*cumul_gain = 0.03125 * MAX32(1024, *cumul_gain) * params->gain_cdbk[4 * best_gain_index + 3];
#endif
/*printf ("%f\n", cumul_gain);*/
/*printf ("encode pitch: %d %d\n", best_pitch, best_gain_index);*/
SPEEX_COPY(exc, best_exc, nsf);
SPEEX_COPY(target, best_target, nsf);
#ifdef FIXED_POINT
/* Scale target back up if needed */
if (scaledown) {
for (i = 0; i < nsf; i++)
target[i] = SHL16(target[i], 1);
}
#endif
return pitch;
}
/** Finds the best quantized 3-tap pitch predictor by analysis by synthesis */
int pitch_search_3tap(
spx_sig_t target[], /* Target vector */
spx_sig_t *sw,
spx_coef_t ak[], /* LPCs for this subframe */
spx_coef_t awk1[], /* Weighted LPCs #1 for this subframe */
spx_coef_t awk2[], /* Weighted LPCs #2 for this subframe */
spx_sig_t exc[], /* Excitation */
const void *par,
int start, /* Smallest pitch value allowed */
int end, /* Largest pitch value allowed */
spx_word16_t pitch_coef, /* Voicing (pitch) coefficient */
int p, /* Number of LPC coeffs */
int nsf, /* Number of samples in subframe */
SpeexBits *bits,
char *stack,
spx_sig_t *exc2,
spx_word16_t *r,
int complexity,
int cdbk_offset,
int plc_tuning
)
{
int i,j;
int cdbk_index, pitch=0, best_gain_index=0;
VARDECL(spx_sig_t *best_exc);
VARDECL(spx_sig_t *new_target);
VARDECL(spx_sig_t *best_target);
int best_pitch=0;
spx_word64_t err, best_err=-1;
int N;
const ltp_params *params;
VARDECL(int *nbest);
N=complexity;
if (N>10)
N=10;
if (N<1)
N=1;
ALLOC(nbest, N, int);
params = (const ltp_params*) par;
if (end<start)
{
speex_bits_pack(bits, 0, params->pitch_bits);
speex_bits_pack(bits, 0, params->gain_bits);
for (i=0; i<nsf; i++)
exc[i]=0;
return start;
}
ALLOC(best_exc, nsf, spx_sig_t);
ALLOC(new_target, nsf, spx_sig_t);
ALLOC(best_target, nsf, spx_sig_t);
if (N>end-start+1)
N=end-start+1;
open_loop_nbest_pitch(sw, start, end, nsf, nbest, NULL, N, stack);
for (i=0; i<N; i++)
{
pitch=nbest[i];
for (j=0; j<nsf; j++)
exc[j]=0;
err=pitch_gain_search_3tap(target, ak, awk1, awk2, exc, par, pitch, p, nsf,
bits, stack, exc2, r, new_target, &cdbk_index, cdbk_offset, plc_tuning);
if (err<best_err || best_err<0)
{
for (j=0; j<nsf; j++)
best_exc[j]=exc[j];
for (j=0; j<nsf; j++)
best_target[j]=new_target[j];
best_err=err;
best_pitch=pitch;
best_gain_index=cdbk_index;
}
}
/*printf ("pitch: %d %d\n", best_pitch, best_gain_index);*/
speex_bits_pack(bits, best_pitch-start, params->pitch_bits);
speex_bits_pack(bits, best_gain_index, params->gain_bits);
/*printf ("encode pitch: %d %d\n", best_pitch, best_gain_index);*/
for (i=0; i<nsf; i++)
exc[i]=best_exc[i];
for (i=0; i<nsf; i++)
target[i]=best_target[i];
return pitch;
}