/*====================================================================================
EVS Codec 3GPP TS26.443 Jun 30, 2015. Version CR 26.443-0006
====================================================================================*/
#include <math.h>
#include "options.h"
#include "cnst.h"
#include "rom_com.h"
#include "prot.h"
/*-------------------------------------------------------------------*
* Local constantes
*-------------------------------------------------------------------*/
#define NB_VOIC 13
#define DIV_NB_VOIC (1.0f/NB_VOIC)
#define ALPA 0.95f
#define ALPAM1 (1.0f-ALPA)
#define BETA (ALPAM1/2.0f)
#define AFREQ_THR 2
#define GPIT_THR 0.4f
#define HANGOVER_DELAY 2
/*-------------------------------------------------------------------*
* Pit_exc_contribution_len()
*
* Determine up to which band the pit contribution is significant
*-------------------------------------------------------------------*/
short Pit_exc_contribution_len( /* o : bin where pitch contribution is significant */
Encoder_State *st, /* i/o: state structure */
const float *dct_res, /* i : DCT of residual */
float *dct_pitex, /* i/o: DCT of pitch contribution */
float *pitch_buf, /* i/o: Pitch per subframe */
short *hangover, /* i : hangover for the time contribution switching */
const short coder_type /* i : coding type */
)
{
float corr_dct_pit[MBANDS_LOC], corr_tmp;
float av_corr, min_corr, ftmp;
short freq, i, j;
short last_pit_band, pit_contr_idx, last_pit_bin;
float ener_res;
float ener_pit;
float low_pit, F1st_harm, F8th_harm;
float corr_dct_pit_tmp[MBANDS_LOC];
short time_flg = 0;
short Len, max_len;
short tmp_dec;
short Mbands_loc = MBANDS_LOC-2;
if(st->L_frame == L_FRAME16k )
{
Mbands_loc = MBANDS_LOC;
}
minimum( pitch_buf, st->L_frame >> 6, &low_pit );
F1st_harm = 12800.0f/low_pit;
F8th_harm = 8.0f*F1st_harm;
freq = 0;
for (i = 0; i <Mbands_loc; i++)
{
corr_tmp = 0.0f;
ener_res = 0.1f;
ener_pit = 0.1f;
for (j = 0; j < mfreq_bindiv_loc[i]; j++)
{
corr_tmp+=dct_res[j+freq]*dct_pitex[j+freq];
ener_res+=dct_res[j+freq]*dct_res[j+freq];
ener_pit+=dct_pitex[j+freq]*dct_pitex[j+freq];
}
corr_dct_pit[i] = (float)(corr_tmp / sqrt(ener_res*ener_pit));
freq += mfreq_bindiv_loc[i];
}
/* Smooth the inter-correlation value and skip the last band for the average (since last band is almost always 0)*/
corr_dct_pit_tmp[0] = ALPA*corr_dct_pit[0]+ALPAM1*corr_dct_pit[1];
if( corr_dct_pit_tmp[0] < 0.5f )
{
corr_dct_pit_tmp[0] = 0.5f;
}
corr_dct_pit_tmp[0] = (corr_dct_pit_tmp[0]-0.5f) *2.0f ;
for (i = 1; i <Mbands_loc-1; i++)
{
corr_dct_pit_tmp[i] = ALPA*corr_dct_pit[i]+BETA*corr_dct_pit[i+1]+BETA*corr_dct_pit[i-1];
if(corr_dct_pit_tmp[i] < 0.5f)
{
corr_dct_pit_tmp[i] = 0.5f;
}
corr_dct_pit_tmp[i] = (corr_dct_pit_tmp[i]-0.5f) *2.0f ;
}
corr_dct_pit_tmp[i] = ALPA*corr_dct_pit[i]+ALPAM1*corr_dct_pit[i-1];
if( corr_dct_pit_tmp[i] < 0.5f )
{
corr_dct_pit_tmp[i] = 0.5f;
}
corr_dct_pit_tmp[i] = (corr_dct_pit_tmp[i] - 0.5f) * 2.0f ;
for (i = 0; i <Mbands_loc; i++)
{
corr_dct_pit[i] = corr_dct_pit_tmp[i];
}
av_corr = DIV_NB_VOIC * corr_dct_pit[0];
for (i = 1; i <NB_VOIC; i++)
{
av_corr += DIV_NB_VOIC*corr_dct_pit[i];
}
/* Find the cut-off freq similarly to HSX */
last_pit_band = 0;
av_corr *= 6400;
if( st->core_brate < ACELP_9k60 )
{
/* Correlation really poor at low rate, time domain still valide */
av_corr *= 2.0;
}
min_corr =(float)fabs(mfreq_loc[0] - av_corr);
for (i = 1; i <Mbands_loc; i++)
{
ftmp = (float)fabs(mfreq_loc[i] - av_corr);
if( ftmp < min_corr )
{
last_pit_band = i;
min_corr = ftmp;
}
}
if( F8th_harm > mfreq_loc[last_pit_band] )
{
do
{
last_pit_band++;
}
while( F8th_harm >= mfreq_loc[last_pit_band] );
}
if( last_pit_band > 7+BAND1k2 && (st->core_brate < CFREQ_BITRATE || st->bwidth == NB) )
{
last_pit_band = 7+BAND1k2;
}
else if ( last_pit_band > 10+BAND1k2 && st->core_brate >= CFREQ_BITRATE )
{
last_pit_band = 10+BAND1k2;
}
time_flg = 0;
if( (st->mem_last_pit_band > 0 && st->old_corr > 0.5f && st->mold_corr > 0.5f && st->lt_gpitch >= 1.5f*GPIT_THR )
|| (last_pit_band > 6)
|| (last_pit_band >= 4 && st->lt_gpitch >= 1.5f*GPIT_THR && st->old_corr > 0.7f)
|| (last_pit_band > BAND1k2 && st->mold_corr > 0.80f && st->lt_gpitch >= GPIT_THR) )
{
tmp_dec = 1;
}
else
{
tmp_dec = 0;
}
/* Different past and current decision */
if ( (st->mem_last_pit_band == 0 && tmp_dec == 1) || (st->mem_last_pit_band > 0 && tmp_dec == 0) )
{
if( *hangover == 0 )
{
time_flg = tmp_dec;
*hangover = HANGOVER_DELAY;
}
else
{
time_flg = 0;
if( st->mem_last_pit_band > 0 )
{
time_flg = 1;
}
(*hangover) -= 1;
if( *hangover < 0 )
{
*hangover = 0;
}
}
}
else
{
time_flg = tmp_dec;
*hangover = HANGOVER_DELAY;
}
/* Decicison on final lenght of time contribution */
pit_contr_idx = 0;
if( time_flg == 1 || coder_type != INACTIVE || st->GSC_noisy_speech )
{
if( st->core_brate <ACELP_9k60 && low_pit < 64 )
{
last_pit_band = 9+BAND1k2;
if(st->bwidth == NB)
{
last_pit_band = 7+BAND1k2;
}
}
else if(st->core_brate < ACELP_9k60 && low_pit < 128)
{
last_pit_band = 5+BAND1k2;
}
else if(st->core_brate < ACELP_9k60 )
{
last_pit_band = 3+BAND1k2;
}
else if( last_pit_band < BAND1k2+1 )
{
last_pit_band = BAND1k2+1;
}
last_pit_bin = (short)(mfreq_loc[last_pit_band]/BIN_SIZE);
st->bpf_off = 0;
max_len = st->L_frame-last_pit_bin;
if( st->bwidth == NB )
{
max_len = 160-last_pit_bin;
}
Len = 80;
if( max_len < 80 )
{
Len = max_len;
}
if(st->core_brate == ACELP_8k00 && st->bwidth != NB )
{
for (i=0; i < max_len; i++)
{
dct_pitex[i+last_pit_bin] = 0.0f;
}
}
else
{
for (i = 0; i < Len; i++)
{
dct_pitex[i+last_pit_bin] *= sm_table[i];
}
for (; i < max_len; i++)
{
dct_pitex[i+last_pit_bin] = 0.0f;
}
}
st->mem_last_pit_band = last_pit_band;
pit_contr_idx = last_pit_band-BAND1k2;
}
else
{
set_f(dct_pitex, 0.0f, st->L_frame);
st->bpf_off = 1;
last_pit_bin = 0;
last_pit_band = 0;
pit_contr_idx = 0;
st->mem_last_pit_band = 0;
set_f( pitch_buf, (float)L_SUBFR, NB_SUBFR );
/* pitch contribution useless - delete all previously written indices belonging to pitch contribution */
for( i = TAG_ACELP_SUBFR_LOOP_START; i < TAG_ACELP_SUBFR_LOOP_END; i++ )
{
if( st->ind_list[i].nb_bits != -1 )
{
st->nb_bits_tot -= st->ind_list[i].nb_bits;
st->ind_list[i].nb_bits = -1;
}
}
if( st->ind_list[IND_ES_PRED].nb_bits != -1 )
{
st->nb_bits_tot -= st->ind_list[IND_ES_PRED].nb_bits;
st->ind_list[IND_ES_PRED].nb_bits = -1;
}
}
if( st->core_brate < CFREQ_BITRATE )
{
if( st->core_brate < ACELP_9k60 )
{
if( pit_contr_idx > 0 )
{
pit_contr_idx = 1;
}
if( coder_type == INACTIVE )
{
push_indice( st, IND_PIT_CONTR_IDX, pit_contr_idx, 1 );
}
}
else
{
push_indice( st, IND_PIT_CONTR_IDX, pit_contr_idx, 3 );
}
}
else
{
push_indice( st, IND_PIT_CONTR_IDX, pit_contr_idx, 4 );
}
return last_pit_bin;
}