ref: d513d743fb5d9802e2d39d74a13f5628c1553059
dir: /src_FIX/SKP_Silk_find_pred_coefs_FIX.c/
/***********************************************************************
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BY THIS LICENSE. THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
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OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
***********************************************************************/
#include "SKP_Silk_main_FIX.h"
#ifdef SAVE_ALL_INTERNAL_DATA
#include <math.h>
void SKP_Silk_LTP_ana_core(
SKP_float r_LPC[], /* I LPC residual */
SKP_float r_LTP[], /* O LTP residual */
const SKP_int pitchL[], /* I pitch lags */
const SKP_float LTPCoef[], /* I LTP Coeficients */
SKP_int subfr_length, /* I smpls in one sub frame */
SKP_int LTP_mem_length /* I Length of LTP state of input */
);
void SKP_Silk_LPC_analysis_filter_FLP(
SKP_float r_LPC[], /* O LPC residual signal */
const SKP_float PredCoef[], /* I LPC coeficicnts */
const SKP_float s[], /* I Input Signal */
SKP_int length, /* I length of signal */
SKP_int Order /* I LPC order */
);
double SKP_Silk_energy_FLP(
const SKP_float *data,
SKP_int dataSize
);
/* integer to floating-point conversion */
SKP_INLINE void SKP_short2float_array(
SKP_float *out,
const SKP_int16 *in,
SKP_int32 length
);
SKP_INLINE SKP_float SKP_Silk_log2( double x ) { return ( SKP_float )( 3.32192809488736 * log10( x ) ); }
#endif
void SKP_Silk_find_pred_coefs_FIX(
SKP_Silk_encoder_state_FIX *psEnc, /* I/O encoder state */
SKP_Silk_encoder_control_FIX *psEncCtrl, /* I/O encoder control */
const SKP_int16 res_pitch[] /* I Residual from pitch analysis */
)
{
SKP_int i;
SKP_int32 WLTP[ MAX_NB_SUBFR * LTP_ORDER * LTP_ORDER ];
SKP_int32 invGains_Q16[ MAX_NB_SUBFR ], local_gains[ MAX_NB_SUBFR ], Wght_Q15[ MAX_NB_SUBFR ];
SKP_int NLSF_Q15[ MAX_LPC_ORDER ];
const SKP_int16 *x_ptr;
SKP_int16 *x_pre_ptr, LPC_in_pre[ MAX_NB_SUBFR * MAX_LPC_ORDER + MAX_FRAME_LENGTH ];
SKP_int32 tmp, min_gain_Q16;
SKP_int LTP_corrs_rshift[ MAX_NB_SUBFR ];
#ifdef SAVE_ALL_INTERNAL_DATA
SKP_int16 uq_PredCoef_Q12[ MAX_NB_SUBFR >> 1 ][ MAX_LPC_ORDER ];
SKP_float uq_PredCoef[ MAX_NB_SUBFR >> 1 ][ MAX_LPC_ORDER ];
SKP_float uq_LTPCoef[ MAX_NB_SUBFR * LTP_ORDER ];
#endif
/* weighting for weighted least squares */
min_gain_Q16 = SKP_int32_MAX >> 6;
for( i = 0; i < psEnc->sCmn.nb_subfr; i++ ) {
min_gain_Q16 = SKP_min( min_gain_Q16, psEncCtrl->Gains_Q16[ i ] );
}
for( i = 0; i < psEnc->sCmn.nb_subfr; i++ ) {
/* Divide to Q16 */
SKP_assert( psEncCtrl->Gains_Q16[ i ] > 0 );
/* Invert and normalize gains, and ensure that maximum invGains_Q16 is within range of a 16 bit int */
invGains_Q16[ i ] = SKP_DIV32_varQ( min_gain_Q16, psEncCtrl->Gains_Q16[ i ], 16 - 2 );
/* Ensure Wght_Q15 a minimum value 1 */
invGains_Q16[ i ] = SKP_max( invGains_Q16[ i ], 363 );
/* Square the inverted gains */
SKP_assert( invGains_Q16[ i ] == SKP_SAT16( invGains_Q16[ i ] ) );
tmp = SKP_SMULWB( invGains_Q16[ i ], invGains_Q16[ i ] );
Wght_Q15[ i ] = SKP_RSHIFT( tmp, 1 );
/* Invert the inverted and normalized gains */
local_gains[ i ] = SKP_DIV32( ( 1 << 16 ), invGains_Q16[ i ] );
}
if( psEncCtrl->sCmn.sigtype == SIG_TYPE_VOICED ) {
/**********/
/* VOICED */
/**********/
SKP_assert( psEnc->sCmn.ltp_mem_length - psEnc->sCmn.predictLPCOrder >= psEncCtrl->sCmn.pitchL[ 0 ] + LTP_ORDER / 2 );
/* LTP analysis */
SKP_Silk_find_LTP_FIX( psEncCtrl->LTPCoef_Q14, WLTP, &psEncCtrl->LTPredCodGain_Q7,
res_pitch, psEncCtrl->sCmn.pitchL, Wght_Q15, psEnc->sCmn.subfr_length,
psEnc->sCmn.nb_subfr, psEnc->sCmn.ltp_mem_length, LTP_corrs_rshift );
#ifdef SAVE_ALL_INTERNAL_DATA
/* Save unquantized LTP coefficients */
for( i = 0; i < LTP_ORDER * psEnc->sCmn.nb_subfr; i++ ) {
uq_LTPCoef[ i ] = (SKP_float)psEncCtrl->LTPCoef_Q14[ i ] / 16384.0f;
}
#endif
/* Quantize LTP gain parameters */
SKP_Silk_quant_LTP_gains_FIX( psEncCtrl->LTPCoef_Q14, psEncCtrl->sCmn.LTPIndex, &psEncCtrl->sCmn.PERIndex,
WLTP, psEnc->mu_LTP_Q8, psEnc->sCmn.LTPQuantLowComplexity, psEnc->sCmn.nb_subfr);
/* Control LTP scaling */
SKP_Silk_LTP_scale_ctrl_FIX( psEnc, psEncCtrl );
/* Create LTP residual */
SKP_Silk_LTP_analysis_filter_FIX( LPC_in_pre, psEnc->x_buf + psEnc->sCmn.ltp_mem_length - psEnc->sCmn.predictLPCOrder,
psEncCtrl->LTPCoef_Q14, psEncCtrl->sCmn.pitchL, invGains_Q16, psEnc->sCmn.subfr_length, psEnc->sCmn.nb_subfr, psEnc->sCmn.predictLPCOrder );
} else {
/************/
/* UNVOICED */
/************/
/* Create signal with prepended subframes, scaled by inverse gains */
x_ptr = psEnc->x_buf + psEnc->sCmn.ltp_mem_length - psEnc->sCmn.predictLPCOrder;
x_pre_ptr = LPC_in_pre;
for( i = 0; i < psEnc->sCmn.nb_subfr; i++ ) {
SKP_Silk_scale_copy_vector16( x_pre_ptr, x_ptr, invGains_Q16[ i ],
psEnc->sCmn.subfr_length + psEnc->sCmn.predictLPCOrder );
x_pre_ptr += psEnc->sCmn.subfr_length + psEnc->sCmn.predictLPCOrder;
x_ptr += psEnc->sCmn.subfr_length;
}
SKP_memset( psEncCtrl->LTPCoef_Q14, 0, psEnc->sCmn.nb_subfr * LTP_ORDER * sizeof( SKP_int16 ) );
psEncCtrl->LTPredCodGain_Q7 = 0;
}
/* LPC_in_pre contains the LTP-filtered input for voiced, and the unfiltered input for unvoiced */
TIC(FIND_LPC)
SKP_Silk_find_LPC_FIX( NLSF_Q15, &psEncCtrl->sCmn.NLSFInterpCoef_Q2, psEnc->sPred.prev_NLSFq_Q15,
psEnc->sCmn.useInterpolatedNLSFs * ( 1 - psEnc->sCmn.first_frame_after_reset ), psEnc->sCmn.predictLPCOrder,
LPC_in_pre, psEnc->sCmn.subfr_length + psEnc->sCmn.predictLPCOrder, psEnc->sCmn.nb_subfr );
TOC(FIND_LPC)
#ifdef SAVE_ALL_INTERNAL_DATA /* Save unquantized LPC's */
if( psEnc->sCmn.useInterpolatedNLSFs == 0 ) {
/* Convert back to filter representation */
SKP_Silk_NLSF2A_stable( uq_PredCoef_Q12[ 0 ], NLSF_Q15, psEnc->sCmn.predictLPCOrder );
SKP_memcpy( uq_PredCoef_Q12[ 1 ], uq_PredCoef_Q12[ 0 ], psEnc->sCmn.predictLPCOrder * sizeof( SKP_int16 ) );
} else { /* i.e. if( psEnc->useInterpolatedLSFs != 0 ) */
SKP_int iNLSF_Q15[ MAX_LPC_ORDER ];
/* Update interpolated LSF0 coefficients taking quantization of LSF1 coefficients into account */
SKP_Silk_interpolate( iNLSF_Q15, psEnc->sPred.prev_NLSFq_Q15, NLSF_Q15,
psEncCtrl->sCmn.NLSFInterpCoef_Q2, psEnc->sCmn.predictLPCOrder );
/* Convert back to filter representation */
SKP_Silk_NLSF2A_stable( uq_PredCoef_Q12[ 0 ], iNLSF_Q15, psEnc->sCmn.predictLPCOrder );
/* Convert back to filter representation */
SKP_Silk_NLSF2A_stable( uq_PredCoef_Q12[ 1 ], NLSF_Q15, psEnc->sCmn.predictLPCOrder );
}
/* Convert to FLP */
for( i = 0; i < psEnc->sCmn.predictLPCOrder; i++ ) {
uq_PredCoef[ 0 ][ i ] = (SKP_float)uq_PredCoef_Q12[ 0 ][ i ] / 4096.0f;
uq_PredCoef[ 1 ][ i ] = (SKP_float)uq_PredCoef_Q12[ 1 ][ i ] / 4096.0f;
}
#endif
/* Quantize LSFs */
TIC(PROCESS_LSFS)
SKP_Silk_process_NLSFs_FIX( psEnc, psEncCtrl, NLSF_Q15 );
TOC(PROCESS_LSFS)
/* Calculate residual energy using quantized LPC coefficients */
SKP_Silk_residual_energy_FIX( psEncCtrl->ResNrg, psEncCtrl->ResNrgQ, LPC_in_pre, psEncCtrl->PredCoef_Q12, local_gains,
psEnc->sCmn.subfr_length, psEnc->sCmn.nb_subfr, psEnc->sCmn.predictLPCOrder );
/* Copy to prediction struct for use in next frame for fluctuation reduction */
SKP_memcpy( psEnc->sPred.prev_NLSFq_Q15, NLSF_Q15, psEnc->sCmn.predictLPCOrder * sizeof( SKP_int ) );
#ifdef SAVE_ALL_INTERNAL_DATA
{
SKP_int j, k;
SKP_float in_nrg, *in_ptr;
SKP_float LPC_res_nrg, qLPC_res_nrg, LTP_res_nrg, qLTP_res_nrg;
SKP_float LPC_predCodGain, QLPC_predCodGain, QLTP_predCodGain, LTPredCodGain, predCodGain;
SKP_float LPC_res[ MAX_FRAME_LENGTH << 1 ], LTP_res[ MAX_FRAME_LENGTH ];
SKP_float SF_resNrg[ MAX_NB_SUBFR ];
SKP_float x_flp[ 2 * MAX_FRAME_LENGTH ];
SKP_float Wght[ MAX_NB_SUBFR ];
SKP_float PredCoef[ 2 ][ MAX_LPC_ORDER ];
SKP_float LTPCoef[ MAX_NB_SUBFR * LTP_ORDER ];
/* Convert various FIX data to FLP */
SKP_short2float_array( x_flp, psEnc->x_buf, psEnc->sCmn.ltp_mem_length + psEnc->sCmn.frame_length );
for( k = 0; k < psEnc->sCmn.nb_subfr; k++ ) {
Wght[ k ] = ( (SKP_float)Wght_Q15[ k ] / 32768.0f );
}
for( i = 0; i < psEnc->sCmn.predictLPCOrder; i++ ) {
PredCoef[ 0 ][ i ] = (SKP_float)psEncCtrl->PredCoef_Q12[ 0 ][ i ] / 4096.0f;
PredCoef[ 1 ][ i ] = (SKP_float)psEncCtrl->PredCoef_Q12[ 1 ][ i ] / 4096.0f;
}
for( i = 0; i < psEnc->sCmn.nb_subfr * LTP_ORDER; i++ ) {
LTPCoef[ i ] = (SKP_float)psEncCtrl->LTPCoef_Q14[ i ] / 16384.0f;
}
/* Weighted input energy */
in_ptr = &x_flp[ psEnc->sCmn.ltp_mem_length ];
DEBUG_STORE_DATA( x_flp.dat, x_flp, psEnc->sCmn.frame_length * sizeof( SKP_float ) );
DEBUG_STORE_DATA( in_ptr.dat, in_ptr, psEnc->sCmn.frame_length * sizeof( SKP_float ) );
in_nrg = 0.0f;
for( k = 0; k < psEnc->sCmn.nb_subfr; k++ ) {
in_nrg += (SKP_float)SKP_Silk_energy_FLP( in_ptr, psEnc->sCmn.subfr_length ) * Wght[ k ];
in_ptr += psEnc->sCmn.subfr_length;
}
if( psEnc->sCmn.useInterpolatedNLSFs == 0 ) {
SKP_memcpy( PredCoef[ 0 ], PredCoef[ 1 ], psEnc->sCmn.predictLPCOrder * sizeof( SKP_float ) );
}
DEBUG_STORE_DATA( uq_PredCoef.dat, uq_PredCoef[0], psEnc->sCmn.predictLPCOrder * sizeof( SKP_float ) );
DEBUG_STORE_DATA( PredCoef.dat, PredCoef[0], psEnc->sCmn.predictLPCOrder * sizeof( SKP_float ) );
LPC_res_nrg = 0.0f;
LTP_res_nrg = 0.0f;
qLPC_res_nrg = 0.0f;
qLTP_res_nrg = 0.0f;
for( j = 0; j < psEnc->sCmn.nb_subfr; j += 2 ) {
/* Calculate LPC residual with unquantized LPC */
SKP_Silk_LPC_analysis_filter_FLP( LPC_res, uq_PredCoef[ j >> 1 ], x_flp + j * psEnc->sCmn.subfr_length,
( psEnc->sCmn.ltp_mem_length + ( psEnc->sCmn.subfr_length << 1 ) ), psEnc->sCmn.predictLPCOrder );
/* Weighted energy */
in_ptr = &LPC_res[ psEnc->sCmn.ltp_mem_length ];
for( k = 0; k < 2; k++ ) {
LPC_res_nrg += (SKP_float)SKP_Silk_energy_FLP( in_ptr, psEnc->sCmn.subfr_length ) * Wght[ j + k ];
in_ptr += psEnc->sCmn.subfr_length;
}
if( psEncCtrl->sCmn.sigtype == SIG_TYPE_VOICED ) {
/* Calculate LTP residual with unquantized LTP and unquantized LPC */
SKP_Silk_LTP_ana_core( LPC_res, LTP_res, &psEncCtrl->sCmn.pitchL[ j ],
&uq_LTPCoef[ j * LTP_ORDER ], psEnc->sCmn.subfr_length, psEnc->sCmn.ltp_mem_length );
/* Weighted energy */
in_ptr = LTP_res;
for( k = 0; k < 2; k++ ) {
LTP_res_nrg += (SKP_float)SKP_Silk_energy_FLP( in_ptr, psEnc->sCmn.subfr_length ) * Wght[ j + k ];
in_ptr += psEnc->sCmn.subfr_length;
}
}
/* Calculate LPC residual with quantized LPC */
SKP_Silk_LPC_analysis_filter_FLP( LPC_res, PredCoef[ j >> 1 ], x_flp + j * psEnc->sCmn.subfr_length,
( psEnc->sCmn.ltp_mem_length + ( psEnc->sCmn.subfr_length << 1 ) ), psEnc->sCmn.predictLPCOrder );
/* Weighted energy */
in_ptr = &LPC_res[ psEnc->sCmn.ltp_mem_length ];
for( k = 0; k < 2; k++ ) {
SF_resNrg[ k + j ] = (SKP_float)SKP_Silk_energy_FLP( in_ptr, psEnc->sCmn.subfr_length );
qLPC_res_nrg += SF_resNrg[ k + j ] * Wght[ j + k ];
in_ptr += psEnc->sCmn.subfr_length;
}
if( psEncCtrl->sCmn.sigtype == SIG_TYPE_VOICED ) {
/* Calculate LTP residual with unquantized LTP and unquantized LPC */
SKP_Silk_LTP_ana_core( LPC_res, LTP_res, &psEncCtrl->sCmn.pitchL[ j ],
<PCoef[ j * LTP_ORDER ], psEnc->sCmn.subfr_length, psEnc->sCmn.ltp_mem_length );
/* Weighted energy */
in_ptr = LTP_res;
for( k = 0; k < 2; k++ ) {
SF_resNrg[ k + j ] = (SKP_float)SKP_Silk_energy_FLP( in_ptr, psEnc->sCmn.subfr_length );
qLTP_res_nrg += SF_resNrg[ k + j ] * Wght[ j + k ];
in_ptr += psEnc->sCmn.subfr_length;
}
} else {
SKP_memcpy( LTP_res, &LPC_res[ psEnc->sCmn.ltp_mem_length ], ( psEnc->sCmn.subfr_length << 1 ) * sizeof( SKP_float ) );
}
/* Save residual */
DEBUG_STORE_DATA( LPC_res.dat, &LPC_res[ psEnc->sCmn.ltp_mem_length ], ( psEnc->sCmn.subfr_length << 1 ) * sizeof( SKP_float ) );
DEBUG_STORE_DATA( res.dat, LTP_res, ( psEnc->sCmn.subfr_length << 1 ) * sizeof( SKP_float ) );
}
if( psEncCtrl->sCmn.sigtype == SIG_TYPE_VOICED ) {
LPC_predCodGain = 3.0f * SKP_Silk_log2( in_nrg / LPC_res_nrg );
QLPC_predCodGain = 3.0f * SKP_Silk_log2( in_nrg / qLPC_res_nrg );
LTPredCodGain = 3.0f * SKP_Silk_log2( LPC_res_nrg / LTP_res_nrg );
QLTP_predCodGain = 3.0f * SKP_Silk_log2( qLPC_res_nrg / qLTP_res_nrg );
} else {
LPC_predCodGain = 3.0f * SKP_Silk_log2( in_nrg / LPC_res_nrg );
QLPC_predCodGain = 3.0f * SKP_Silk_log2( in_nrg / qLPC_res_nrg );
LTPredCodGain = 0.0f;
QLTP_predCodGain = 0.0f;
}
predCodGain = QLPC_predCodGain + QLTP_predCodGain;
DEBUG_STORE_DATA( LTPredCodGain.dat, <PredCodGain, sizeof( SKP_float ) );
DEBUG_STORE_DATA( QLTP_predCodGain.dat, &QLTP_predCodGain, sizeof( SKP_float ) );
DEBUG_STORE_DATA( LPC_predCodGain.dat, &LPC_predCodGain, sizeof( SKP_float ) );
DEBUG_STORE_DATA( QLPC_predCodGain.dat, &QLPC_predCodGain, sizeof( SKP_float ) );
DEBUG_STORE_DATA( predCodGain.dat, &predCodGain, sizeof( SKP_float ) );
DEBUG_STORE_DATA( ResNrg.dat, SF_resNrg, psEnc->sCmn.nb_subfr * sizeof( SKP_float ) );
}
#endif
}
#ifdef SAVE_ALL_INTERNAL_DATA
/****************************************************/
/* LTP analysis filter. Filters two subframes */
/****************************************************/
void SKP_Silk_LTP_ana_core(
SKP_float r_LPC[], /* I LPC residual */
SKP_float r_LTP[], /* O LTP residual */
const SKP_int pitchL[], /* I pitch lags */
const SKP_float LTPCoef[], /* I LTP Coeficients */
SKP_int subfr_length, /* I smpls in one sub frame */
SKP_int LTP_mem_length /* I Length of LTP state of input */
)
{
SKP_int k, i;
SKP_float LTP_pred;
const SKP_float *r, *b_ptr, *lag_ptr;
r = &r_LPC[ LTP_mem_length ];
b_ptr = LTPCoef;
for( k = 0; k < (MAX_NB_SUBFR >> 1); k++ ) {
lag_ptr = r - pitchL[k];
/* LTP analysis FIR filter */
for( i = 0; i < subfr_length; i++ ) {
/* long-term prediction */
LTP_pred = lag_ptr[LTP_ORDER/2] * b_ptr[0];
LTP_pred += lag_ptr[LTP_ORDER/2 - 1] * b_ptr[1];
LTP_pred += lag_ptr[LTP_ORDER/2 - 2] * b_ptr[2];
LTP_pred += lag_ptr[LTP_ORDER/2 - 3] * b_ptr[3];
LTP_pred += lag_ptr[LTP_ORDER/2 - 4] * b_ptr[4];
/* subtract prediction */
r_LTP[i] = r[i] - LTP_pred;
lag_ptr++;
}
r += subfr_length;
r_LTP += subfr_length;
b_ptr += LTP_ORDER;
}
}
/*******************************************/
/* LPC analysis filter */
/* NB! State is kept internally and the */
/* filter always starts with zero state */
/* first Order output samples are not set */
/*******************************************/
void SKP_Silk_LPC_analysis_filter_FLP(
SKP_float r_LPC[], /* O LPC residual signal */
const SKP_float PredCoef[], /* I LPC coeficicnts */
const SKP_float s[], /* I Input Signal */
SKP_int length, /* I length of signal */
SKP_int Order /* I LPC order */
)
{
SKP_int i, j;
SKP_float LPC_pred;
const SKP_float *s_ptr;
for ( i = Order; i < length; i++ ) {
s_ptr = &s[i - 1];
LPC_pred = 0;
/* short-term prediction */
for( j = 0; j < Order; j++ ) {
LPC_pred += s_ptr[ -j ] * PredCoef[ j ];
}
/* prediction error */
r_LPC[ i ] = s_ptr[ 1 ] - LPC_pred;
}
}
/* sum of squares of a SKP_float array, with result as double */
double SKP_Silk_energy_FLP(
const SKP_float *data,
SKP_int dataSize
)
{
SKP_int i, dataSize4;
double result;
/* 4x unrolled loop */
result = 0.0f;
dataSize4 = dataSize & 0xFFFC;
for( i = 0; i < dataSize4; i += 4 ) {
result += data[ i + 0 ] * data[ i + 0 ] +
data[ i + 1 ] * data[ i + 1 ] +
data[ i + 2 ] * data[ i + 2 ] +
data[ i + 3 ] * data[ i + 3 ];
}
/* add any remaining products */
for( ; i < dataSize; i++ ) {
result += data[ i ] * data[ i ];
}
SKP_assert( result >= 0.0 );
return result;
}
#endif