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 */
const SKP_int16 x[] /* I Speech signal */
)
{
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_int16 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 ];
/* 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( psEnc->sCmn.indices.signalType == TYPE_VOICED ) {
/**********/
/* VOICED */
/**********/
SKP_assert( psEnc->sCmn.ltp_mem_length - psEnc->sCmn.predictLPCOrder >= psEncCtrl->pitchL[ 0 ] + LTP_ORDER / 2 );
/* LTP analysis */
SKP_Silk_find_LTP_FIX( psEncCtrl->LTPCoef_Q14, WLTP, &psEncCtrl->LTPredCodGain_Q7,
res_pitch, psEncCtrl->pitchL, Wght_Q15, psEnc->sCmn.subfr_length,
psEnc->sCmn.nb_subfr, psEnc->sCmn.ltp_mem_length, LTP_corrs_rshift );
/* Quantize LTP gain parameters */
SKP_Silk_quant_LTP_gains( psEncCtrl->LTPCoef_Q14, psEnc->sCmn.indices.LTPIndex, &psEnc->sCmn.indices.PERIndex,
WLTP, psEnc->sCmn.mu_LTP_Q9, 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->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 = x - 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, &psEnc->sCmn.indices.NLSFInterpCoef_Q2, psEnc->sCmn.prev_NLSFq_Q15,
psEnc->sCmn.useInterpolatedNLSFs, 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)
/* Quantize LSFs */
TIC(PROCESS_LSFS)
SKP_Silk_process_NLSFs( &psEnc->sCmn, psEncCtrl->PredCoef_Q12, NLSF_Q15, psEnc->sCmn.prev_NLSFq_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->sCmn.prev_NLSFq_Q15, NLSF_Q15, sizeof( psEnc->sCmn.prev_NLSFq_Q15 ) );
}
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 int16_t res_pitch[] /* I Residual from pitch analysis */
)
{
int i;
int32_t WLTP[NB_SUBFR * LTP_ORDER * LTP_ORDER];
int32_t invGains_Q16[NB_SUBFR], local_gains_Qx[NB_SUBFR],
Wght_Q15[NB_SUBFR];
int NLSF_Q15[MAX_LPC_ORDER];
const int16_t *x_ptr;
int16_t *x_pre_ptr,
LPC_in_pre[NB_SUBFR * MAX_LPC_ORDER + MAX_FRAME_LENGTH];
int32_t tmp, min_gain_Q16;
#if !VARQ
int LZ;
#endif
int LTP_corrs_rshift[NB_SUBFR];
/* weighting for weighted least squares */
min_gain_Q16 = int32_t_MAX >> 6;
for (i = 0; i < NB_SUBFR; i++) {
min_gain_Q16 = SKP_min(min_gain_Q16, psEncCtrl->Gains_Q16[i]);
}
#if !VARQ
LZ = SKP_Silk_CLZ32(min_gain_Q16) - 1;
LZ = SKP_LIMIT(LZ, 0, 16);
min_gain_Q16 = SKP_RSHIFT(min_gain_Q16, 2); /* Ensure that maximum invGains_Q16 is within range of a 16 bit int */
#endif
for (i = 0; i < NB_SUBFR; i++) {
/* Divide to Q16 */
assert(psEncCtrl->Gains_Q16[i] > 0);
#if VARQ
/* 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);
#else
invGains_Q16[i] =
SKP_DIV32(SKP_LSHIFT(min_gain_Q16, LZ),
SKP_RSHIFT(psEncCtrl->Gains_Q16[i], 16 - LZ));
#endif
/* Ensure Wght_Q15 a minimum value 1 */
invGains_Q16[i] = SKP_max(invGains_Q16[i], 363);
/* Square the inverted gains */
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_Qx[i] =
SKP_DIV32((1 << (16 + Qx)), invGains_Q16[i]);
}
if (psEncCtrl->sCmn.sigtype == SIG_TYPE_VOICED) {
/**********/
/* VOICED */
/**********/
assert(psEnc->sCmn.frame_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,
res_pitch +
SKP_RSHIFT(psEnc->sCmn.frame_length, 1),
psEncCtrl->sCmn.pitchL, Wght_Q15,
psEnc->sCmn.subfr_length,
psEnc->sCmn.frame_length,
LTP_corrs_rshift);
/* 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);
/* 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.frame_length -
psEnc->sCmn.predictLPCOrder,
psEncCtrl->LTPCoef_Q14,
psEncCtrl->sCmn.pitchL,
invGains_Q16, 16,
psEnc->sCmn.subfr_length,
psEnc->sCmn.predictLPCOrder);
} else {
/************/
/* UNVOICED */
/************/
/* Create signal with prepended subframes, scaled by inverse gains */
x_ptr =
psEnc->x_buf + psEnc->sCmn.frame_length -
psEnc->sCmn.predictLPCOrder;
x_pre_ptr = LPC_in_pre;
for (i = 0; i < 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,
NB_SUBFR * LTP_ORDER * sizeof(int16_t));
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);
TOC(FIND_LPC)
/* 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, (const int16_t(*)[])psEncCtrl->PredCoef_Q12,
local_gains_Qx, Qx,
psEnc->sCmn.subfr_length,
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(int));
}