static OPUS_INLINE opus_int16 *silk_resampler_private_down_FIR_INTERPOL( opus_int16 *out, opus_int32 *buf, const opus_int16 *FIR_Coefs, opus_int FIR_Order, opus_int FIR_Fracs, opus_int32 max_index_Q16, opus_int32 index_increment_Q16 ) { opus_int32 index_Q16, res_Q6; opus_int32 *buf_ptr; opus_int32 interpol_ind; const opus_int16 *interpol_ptr; switch( FIR_Order ) { case RESAMPLER_DOWN_ORDER_FIR0: for( index_Q16 = 0; index_Q16 < max_index_Q16; index_Q16 += index_increment_Q16 ) { /* Integer part gives pointer to buffered input */ buf_ptr = buf + silk_RSHIFT( index_Q16, 16 ); /* Fractional part gives interpolation coefficients */ interpol_ind = silk_SMULWB( index_Q16 & 0xFFFF, FIR_Fracs ); /* Inner product */ interpol_ptr = &FIR_Coefs[ RESAMPLER_DOWN_ORDER_FIR0 / 2 * interpol_ind ]; res_Q6 = silk_SMULWB( buf_ptr[ 0 ], interpol_ptr[ 0 ] ); res_Q6 = silk_SMLAWB( res_Q6, buf_ptr[ 1 ], interpol_ptr[ 1 ] ); res_Q6 = silk_SMLAWB( res_Q6, buf_ptr[ 2 ], interpol_ptr[ 2 ] ); res_Q6 = silk_SMLAWB( res_Q6, buf_ptr[ 3 ], interpol_ptr[ 3 ] ); res_Q6 = silk_SMLAWB( res_Q6, buf_ptr[ 4 ], interpol_ptr[ 4 ] ); res_Q6 = silk_SMLAWB( res_Q6, buf_ptr[ 5 ], interpol_ptr[ 5 ] ); res_Q6 = silk_SMLAWB( res_Q6, buf_ptr[ 6 ], interpol_ptr[ 6 ] ); res_Q6 = silk_SMLAWB( res_Q6, buf_ptr[ 7 ], interpol_ptr[ 7 ] ); res_Q6 = silk_SMLAWB( res_Q6, buf_ptr[ 8 ], interpol_ptr[ 8 ] ); interpol_ptr = &FIR_Coefs[ RESAMPLER_DOWN_ORDER_FIR0 / 2 * ( FIR_Fracs - 1 - interpol_ind ) ]; res_Q6 = silk_SMLAWB( res_Q6, buf_ptr[ 17 ], interpol_ptr[ 0 ] ); res_Q6 = silk_SMLAWB( res_Q6, buf_ptr[ 16 ], interpol_ptr[ 1 ] ); res_Q6 = silk_SMLAWB( res_Q6, buf_ptr[ 15 ], interpol_ptr[ 2 ] ); res_Q6 = silk_SMLAWB( res_Q6, buf_ptr[ 14 ], interpol_ptr[ 3 ] ); res_Q6 = silk_SMLAWB( res_Q6, buf_ptr[ 13 ], interpol_ptr[ 4 ] ); res_Q6 = silk_SMLAWB( res_Q6, buf_ptr[ 12 ], interpol_ptr[ 5 ] ); res_Q6 = silk_SMLAWB( res_Q6, buf_ptr[ 11 ], interpol_ptr[ 6 ] ); res_Q6 = silk_SMLAWB( res_Q6, buf_ptr[ 10 ], interpol_ptr[ 7 ] ); res_Q6 = silk_SMLAWB( res_Q6, buf_ptr[ 9 ], interpol_ptr[ 8 ] ); /* Scale down, saturate and store in output array */ *out++ = (opus_int16)silk_SAT16( silk_RSHIFT_ROUND( res_Q6, 6 ) ); } break; case RESAMPLER_DOWN_ORDER_FIR1: for( index_Q16 = 0; index_Q16 < max_index_Q16; index_Q16 += index_increment_Q16 ) { /* Integer part gives pointer to buffered input */ buf_ptr = buf + silk_RSHIFT( index_Q16, 16 ); /* Inner product */ res_Q6 = silk_SMULWB( silk_ADD32( buf_ptr[ 0 ], buf_ptr[ 23 ] ), FIR_Coefs[ 0 ] ); res_Q6 = silk_SMLAWB( res_Q6, silk_ADD32( buf_ptr[ 1 ], buf_ptr[ 22 ] ), FIR_Coefs[ 1 ] ); res_Q6 = silk_SMLAWB( res_Q6, silk_ADD32( buf_ptr[ 2 ], buf_ptr[ 21 ] ), FIR_Coefs[ 2 ] ); res_Q6 = silk_SMLAWB( res_Q6, silk_ADD32( buf_ptr[ 3 ], buf_ptr[ 20 ] ), FIR_Coefs[ 3 ] ); res_Q6 = silk_SMLAWB( res_Q6, silk_ADD32( buf_ptr[ 4 ], buf_ptr[ 19 ] ), FIR_Coefs[ 4 ] ); res_Q6 = silk_SMLAWB( res_Q6, silk_ADD32( buf_ptr[ 5 ], buf_ptr[ 18 ] ), FIR_Coefs[ 5 ] ); res_Q6 = silk_SMLAWB( res_Q6, silk_ADD32( buf_ptr[ 6 ], buf_ptr[ 17 ] ), FIR_Coefs[ 6 ] ); res_Q6 = silk_SMLAWB( res_Q6, silk_ADD32( buf_ptr[ 7 ], buf_ptr[ 16 ] ), FIR_Coefs[ 7 ] ); res_Q6 = silk_SMLAWB( res_Q6, silk_ADD32( buf_ptr[ 8 ], buf_ptr[ 15 ] ), FIR_Coefs[ 8 ] ); res_Q6 = silk_SMLAWB( res_Q6, silk_ADD32( buf_ptr[ 9 ], buf_ptr[ 14 ] ), FIR_Coefs[ 9 ] ); res_Q6 = silk_SMLAWB( res_Q6, silk_ADD32( buf_ptr[ 10 ], buf_ptr[ 13 ] ), FIR_Coefs[ 10 ] ); res_Q6 = silk_SMLAWB( res_Q6, silk_ADD32( buf_ptr[ 11 ], buf_ptr[ 12 ] ), FIR_Coefs[ 11 ] ); /* Scale down, saturate and store in output array */ *out++ = (opus_int16)silk_SAT16( silk_RSHIFT_ROUND( res_Q6, 6 ) ); } break; case RESAMPLER_DOWN_ORDER_FIR2: for( index_Q16 = 0; index_Q16 < max_index_Q16; index_Q16 += index_increment_Q16 ) { /* Integer part gives pointer to buffered input */ buf_ptr = buf + silk_RSHIFT( index_Q16, 16 ); /* Inner product */ res_Q6 = silk_SMULWB( silk_ADD32( buf_ptr[ 0 ], buf_ptr[ 35 ] ), FIR_Coefs[ 0 ] ); res_Q6 = silk_SMLAWB( res_Q6, silk_ADD32( buf_ptr[ 1 ], buf_ptr[ 34 ] ), FIR_Coefs[ 1 ] ); res_Q6 = silk_SMLAWB( res_Q6, silk_ADD32( buf_ptr[ 2 ], buf_ptr[ 33 ] ), FIR_Coefs[ 2 ] ); res_Q6 = silk_SMLAWB( res_Q6, silk_ADD32( buf_ptr[ 3 ], buf_ptr[ 32 ] ), FIR_Coefs[ 3 ] ); res_Q6 = silk_SMLAWB( res_Q6, silk_ADD32( buf_ptr[ 4 ], buf_ptr[ 31 ] ), FIR_Coefs[ 4 ] ); res_Q6 = silk_SMLAWB( res_Q6, silk_ADD32( buf_ptr[ 5 ], buf_ptr[ 30 ] ), FIR_Coefs[ 5 ] ); res_Q6 = silk_SMLAWB( res_Q6, silk_ADD32( buf_ptr[ 6 ], buf_ptr[ 29 ] ), FIR_Coefs[ 6 ] ); res_Q6 = silk_SMLAWB( res_Q6, silk_ADD32( buf_ptr[ 7 ], buf_ptr[ 28 ] ), FIR_Coefs[ 7 ] ); res_Q6 = silk_SMLAWB( res_Q6, silk_ADD32( buf_ptr[ 8 ], buf_ptr[ 27 ] ), FIR_Coefs[ 8 ] ); res_Q6 = silk_SMLAWB( res_Q6, silk_ADD32( buf_ptr[ 9 ], buf_ptr[ 26 ] ), FIR_Coefs[ 9 ] ); res_Q6 = silk_SMLAWB( res_Q6, silk_ADD32( buf_ptr[ 10 ], buf_ptr[ 25 ] ), FIR_Coefs[ 10 ] ); res_Q6 = silk_SMLAWB( res_Q6, silk_ADD32( buf_ptr[ 11 ], buf_ptr[ 24 ] ), FIR_Coefs[ 11 ] ); res_Q6 = silk_SMLAWB( res_Q6, silk_ADD32( buf_ptr[ 12 ], buf_ptr[ 23 ] ), FIR_Coefs[ 12 ] ); res_Q6 = silk_SMLAWB( res_Q6, silk_ADD32( buf_ptr[ 13 ], buf_ptr[ 22 ] ), FIR_Coefs[ 13 ] ); res_Q6 = silk_SMLAWB( res_Q6, silk_ADD32( buf_ptr[ 14 ], buf_ptr[ 21 ] ), FIR_Coefs[ 14 ] ); res_Q6 = silk_SMLAWB( res_Q6, silk_ADD32( buf_ptr[ 15 ], buf_ptr[ 20 ] ), FIR_Coefs[ 15 ] ); res_Q6 = silk_SMLAWB( res_Q6, silk_ADD32( buf_ptr[ 16 ], buf_ptr[ 19 ] ), FIR_Coefs[ 16 ] ); res_Q6 = silk_SMLAWB( res_Q6, silk_ADD32( buf_ptr[ 17 ], buf_ptr[ 18 ] ), FIR_Coefs[ 17 ] ); /* Scale down, saturate and store in output array */ *out++ = (opus_int16)silk_SAT16( silk_RSHIFT_ROUND( res_Q6, 6 ) ); } break; default: silk_assert( 0 ); } return out; }
/* Decode parameters from payload */ void silk_decode_parameters( silk_decoder_state *psDec, /* I/O State */ silk_decoder_control *psDecCtrl, /* I/O Decoder control */ opus_int condCoding /* I The type of conditional coding to use */ ) { opus_int i, k, Ix; opus_int16 pNLSF_Q15[ MAX_LPC_ORDER ], pNLSF0_Q15[ MAX_LPC_ORDER ]; const opus_int8 *cbk_ptr_Q7; /* Dequant Gains */ silk_gains_dequant( psDecCtrl->Gains_Q16, psDec->indices.GainsIndices, &psDec->LastGainIndex, condCoding == CODE_CONDITIONALLY, psDec->nb_subfr ); /****************/ /* Decode NLSFs */ /****************/ silk_NLSF_decode( pNLSF_Q15, psDec->indices.NLSFIndices, psDec->psNLSF_CB ); /* Convert NLSF parameters to AR prediction filter coefficients */ silk_NLSF2A( psDecCtrl->PredCoef_Q12[ 1 ], pNLSF_Q15, psDec->LPC_order ); /* If just reset, e.g., because internal Fs changed, do not allow interpolation */ /* improves the case of packet loss in the first frame after a switch */ if( psDec->first_frame_after_reset == 1 ) { psDec->indices.NLSFInterpCoef_Q2 = 4; } if( psDec->indices.NLSFInterpCoef_Q2 < 4 ) { /* Calculation of the interpolated NLSF0 vector from the interpolation factor, */ /* the previous NLSF1, and the current NLSF1 */ for( i = 0; i < psDec->LPC_order; i++ ) { pNLSF0_Q15[ i ] = psDec->prevNLSF_Q15[ i ] + silk_RSHIFT( silk_MUL( psDec->indices.NLSFInterpCoef_Q2, pNLSF_Q15[ i ] - psDec->prevNLSF_Q15[ i ] ), 2 ); } /* Convert NLSF parameters to AR prediction filter coefficients */ silk_NLSF2A( psDecCtrl->PredCoef_Q12[ 0 ], pNLSF0_Q15, psDec->LPC_order ); } else { /* Copy LPC coefficients for first half from second half */ silk_memcpy( psDecCtrl->PredCoef_Q12[ 0 ], psDecCtrl->PredCoef_Q12[ 1 ], psDec->LPC_order * sizeof( opus_int16 ) ); } silk_memcpy( psDec->prevNLSF_Q15, pNLSF_Q15, psDec->LPC_order * sizeof( opus_int16 ) ); /* After a packet loss do BWE of LPC coefs */ if( psDec->lossCnt ) { silk_bwexpander( psDecCtrl->PredCoef_Q12[ 0 ], psDec->LPC_order, BWE_AFTER_LOSS_Q16 ); silk_bwexpander( psDecCtrl->PredCoef_Q12[ 1 ], psDec->LPC_order, BWE_AFTER_LOSS_Q16 ); } if( psDec->indices.signalType == TYPE_VOICED ) { /*********************/ /* Decode pitch lags */ /*********************/ /* Decode pitch values */ silk_decode_pitch( psDec->indices.lagIndex, psDec->indices.contourIndex, psDecCtrl->pitchL, psDec->fs_kHz, psDec->nb_subfr ); /* Decode Codebook Index */ cbk_ptr_Q7 = silk_LTP_vq_ptrs_Q7[ psDec->indices.PERIndex ]; /* set pointer to start of codebook */ for( k = 0; k < psDec->nb_subfr; k++ ) { Ix = psDec->indices.LTPIndex[ k ]; for( i = 0; i < LTP_ORDER; i++ ) { psDecCtrl->LTPCoef_Q14[ k * LTP_ORDER + i ] = silk_LSHIFT( cbk_ptr_Q7[ Ix * LTP_ORDER + i ], 7 ); } } /**********************/ /* Decode LTP scaling */ /**********************/ Ix = psDec->indices.LTP_scaleIndex; psDecCtrl->LTP_scale_Q14 = silk_LTPScales_table_Q14[ Ix ]; } else { silk_memset( psDecCtrl->pitchL, 0, psDec->nb_subfr * sizeof( opus_int ) ); silk_memset( psDecCtrl->LTPCoef_Q14, 0, LTP_ORDER * psDec->nb_subfr * sizeof( opus_int16 ) ); psDec->indices.PERIndex = 0; psDecCtrl->LTP_scale_Q14 = 0; } }
void silk_prefilter_FIX( silk_encoder_state_FIX *psEnc, /* I/O Encoder state */ const silk_encoder_control_FIX *psEncCtrl, /* I Encoder control */ opus_int32 xw_Q3[], /* O Weighted signal */ const opus_int16 x[] /* I Speech signal */ ) { silk_prefilter_state_FIX *P = &psEnc->sPrefilt; opus_int j, k, lag; opus_int32 tmp_32; const opus_int16 *AR1_shp_Q13; const opus_int16 *px; opus_int32 *pxw_Q3; opus_int HarmShapeGain_Q12, Tilt_Q14; opus_int32 HarmShapeFIRPacked_Q12, LF_shp_Q14; VARDECL(opus_int32, x_filt_Q12); VARDECL(opus_int32, st_res_Q2); opus_int16 B_Q10[2]; SAVE_STACK; /* Set up pointers */ px = x; pxw_Q3 = xw_Q3; lag = P->lagPrev; ALLOC(x_filt_Q12, psEnc->sCmn.subfr_length, opus_int32); ALLOC(st_res_Q2, psEnc->sCmn.subfr_length, opus_int32); for (k = 0; k < psEnc->sCmn.nb_subfr; k++) { /* Update Variables that change per sub frame */ if (psEnc->sCmn.indices.signalType == TYPE_VOICED) { lag = psEncCtrl->pitchL[k]; } /* Noise shape parameters */ HarmShapeGain_Q12 = silk_SMULWB((opus_int32) psEncCtrl->HarmShapeGain_Q14[k], 16384 - psEncCtrl->HarmBoost_Q14[k]); silk_assert(HarmShapeGain_Q12 >= 0); HarmShapeFIRPacked_Q12 = silk_RSHIFT(HarmShapeGain_Q12, 2); HarmShapeFIRPacked_Q12 |= silk_LSHIFT((opus_int32) silk_RSHIFT(HarmShapeGain_Q12, 1), 16); Tilt_Q14 = psEncCtrl->Tilt_Q14[k]; LF_shp_Q14 = psEncCtrl->LF_shp_Q14[k]; AR1_shp_Q13 = &psEncCtrl->AR1_Q13[k * MAX_SHAPE_LPC_ORDER]; /* Short term FIR filtering*/ silk_warped_LPC_analysis_filter_FIX(P->sAR_shp, st_res_Q2, AR1_shp_Q13, px, psEnc->sCmn.warping_Q16, psEnc->sCmn.subfr_length, psEnc->sCmn.shapingLPCOrder); /* Reduce (mainly) low frequencies during harmonic emphasis */ B_Q10[0] = silk_RSHIFT_ROUND(psEncCtrl->GainsPre_Q14[k], 4); tmp_32 = silk_SMLABB(SILK_FIX_CONST(INPUT_TILT, 26), psEncCtrl->HarmBoost_Q14[k], HarmShapeGain_Q12); /* Q26 */ tmp_32 = silk_SMLABB(tmp_32, psEncCtrl->coding_quality_Q14, SILK_FIX_CONST(HIGH_RATE_INPUT_TILT, 12)); /* Q26 */ tmp_32 = silk_SMULWB(tmp_32, -psEncCtrl->GainsPre_Q14[k]); /* Q24 */ tmp_32 = silk_RSHIFT_ROUND(tmp_32, 14); /* Q10 */ B_Q10[1] = silk_SAT16(tmp_32); x_filt_Q12[0] = silk_MLA(silk_MUL(st_res_Q2[0], B_Q10[0]), P->sHarmHP_Q2, B_Q10[1]); for (j = 1; j < psEnc->sCmn.subfr_length; j++) { x_filt_Q12[j] = silk_MLA(silk_MUL(st_res_Q2[j], B_Q10[0]), st_res_Q2[j - 1], B_Q10[1]); } P->sHarmHP_Q2 = st_res_Q2[psEnc->sCmn.subfr_length - 1]; silk_prefilt_FIX(P, x_filt_Q12, pxw_Q3, HarmShapeFIRPacked_Q12, Tilt_Q14, LF_shp_Q14, lag, psEnc->sCmn.subfr_length); px += psEnc->sCmn.subfr_length; pxw_Q3 += psEnc->sCmn.subfr_length; } P->lagPrev = psEncCtrl->pitchL[psEnc->sCmn.nb_subfr - 1]; RESTORE_STACK; }
void silk_find_pred_coefs_FIX( silk_encoder_state_FIX *psEnc, /* I/O encoder state */ silk_encoder_control_FIX *psEncCtrl, /* I/O encoder control */ const opus_int16 res_pitch[], /* I Residual from pitch analysis */ const opus_int16 x[], /* I Speech signal */ opus_int condCoding /* I The type of conditional coding to use */ ) { opus_int i; opus_int32 WLTP[ MAX_NB_SUBFR * LTP_ORDER * LTP_ORDER ]; opus_int32 invGains_Q16[ MAX_NB_SUBFR ], local_gains[ MAX_NB_SUBFR ], Wght_Q15[ MAX_NB_SUBFR ]; opus_int16 NLSF_Q15[ MAX_LPC_ORDER ]; const opus_int16 *x_ptr; opus_int16 *x_pre_ptr, LPC_in_pre[ MAX_NB_SUBFR * MAX_LPC_ORDER + MAX_FRAME_LENGTH ]; opus_int32 tmp, min_gain_Q16; opus_int LTP_corrs_rshift[ MAX_NB_SUBFR ]; /* weighting for weighted least squares */ min_gain_Q16 = silk_int32_MAX >> 6; for( i = 0; i < psEnc->sCmn.nb_subfr; i++ ) { min_gain_Q16 = silk_min( min_gain_Q16, psEncCtrl->Gains_Q16[ i ] ); } for( i = 0; i < psEnc->sCmn.nb_subfr; i++ ) { /* Divide to Q16 */ silk_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 ] = silk_DIV32_varQ( min_gain_Q16, psEncCtrl->Gains_Q16[ i ], 16 - 2 ); /* Ensure Wght_Q15 a minimum value 1 */ invGains_Q16[ i ] = silk_max( invGains_Q16[ i ], 363 ); /* Square the inverted gains */ silk_assert( invGains_Q16[ i ] == silk_SAT16( invGains_Q16[ i ] ) ); tmp = silk_SMULWB( invGains_Q16[ i ], invGains_Q16[ i ] ); Wght_Q15[ i ] = silk_RSHIFT( tmp, 1 ); /* Invert the inverted and normalized gains */ local_gains[ i ] = silk_DIV32( ( 1 << 16 ), invGains_Q16[ i ] ); } if( psEnc->sCmn.indices.signalType == TYPE_VOICED ) { /**********/ /* VOICED */ /**********/ silk_assert( psEnc->sCmn.ltp_mem_length - psEnc->sCmn.predictLPCOrder >= psEncCtrl->pitchL[ 0 ] + LTP_ORDER / 2 ); /* LTP analysis */ 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 */ 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 */ silk_LTP_scale_ctrl_FIX( psEnc, psEncCtrl, condCoding ); /* Create LTP residual */ silk_LTP_analysis_filter_FIX( LPC_in_pre, x - 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++ ) { 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; } silk_memset( psEncCtrl->LTPCoef_Q14, 0, psEnc->sCmn.nb_subfr * LTP_ORDER * sizeof( opus_int16 ) ); psEncCtrl->LTPredCodGain_Q7 = 0; } /* LPC_in_pre contains the LTP-filtered input for voiced, and the unfiltered input for unvoiced */ 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 ); /* Quantize LSFs */ silk_process_NLSFs( &psEnc->sCmn, psEncCtrl->PredCoef_Q12, NLSF_Q15, psEnc->sCmn.prev_NLSFq_Q15 ); /* Calculate residual energy using quantized LPC coefficients */ 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 interpolation */ silk_memcpy( psEnc->sCmn.prev_NLSFq_Q15, NLSF_Q15, sizeof( psEnc->sCmn.prev_NLSFq_Q15 ) ); }
/* compute whitening filter coefficients from normalized line spectral frequencies */ void silk_NLSF2A( opus_int16 *a_Q12, /* O monic whitening filter coefficients in Q12, [ d ] */ const opus_int16 *NLSF, /* I normalized line spectral frequencies in Q15, [ d ] */ const opus_int d /* I filter order (should be even) */ ) { /* This ordering was found to maximize quality. It improves numerical accuracy of silk_NLSF2A_find_poly() compared to "standard" ordering. */ static const unsigned char ordering16[16] = { 0, 15, 8, 7, 4, 11, 12, 3, 2, 13, 10, 5, 6, 9, 14, 1 }; static const unsigned char ordering10[10] = { 0, 9, 6, 3, 4, 5, 8, 1, 2, 7 }; const unsigned char *ordering; opus_int k, i, dd; opus_int32 cos_LSF_QA[ SILK_MAX_ORDER_LPC ]; opus_int32 P[ SILK_MAX_ORDER_LPC / 2 + 1 ], Q[ SILK_MAX_ORDER_LPC / 2 + 1 ]; opus_int32 Ptmp, Qtmp, f_int, f_frac, cos_val, delta; opus_int32 a32_QA1[ SILK_MAX_ORDER_LPC ]; opus_int32 maxabs, absval, idx=0, sc_Q16; silk_assert(LSF_COS_TAB_SZ_FIX == 128); silk_assert(d==10||d==16); /* convert LSFs to 2*cos(LSF), using piecewise linear curve from table */ ordering = d == 16 ? ordering16 : ordering10; for(k = 0; k < d; k++) { silk_assert(NLSF[k] >= 0); /* f_int on a scale 0-127 (rounded down) */ f_int = silk_RSHIFT(NLSF[k], 15 - 7); /* f_frac, range: 0..255 */ f_frac = NLSF[k] - silk_LSHIFT(f_int, 15 - 7); silk_assert(f_int >= 0); silk_assert(f_int < LSF_COS_TAB_SZ_FIX); /* Read start and end value from table */ cos_val = silk_LSFCosTab_FIX_Q12[ f_int ]; /* Q12 */ delta = silk_LSFCosTab_FIX_Q12[ f_int + 1 ] - cos_val; /* Q12, with a range of 0..200 */ /* Linear interpolation */ cos_LSF_QA[ordering[k]] = silk_RSHIFT_ROUND(silk_LSHIFT(cos_val, 8) + silk_MUL(delta, f_frac), 20 - QA); /* QA */ } dd = silk_RSHIFT(d, 1); /* generate even and odd polynomials using convolution */ silk_NLSF2A_find_poly(P, &cos_LSF_QA[ 0 ], dd); silk_NLSF2A_find_poly(Q, &cos_LSF_QA[ 1 ], dd); /* convert even and odd polynomials to opus_int32 Q12 filter coefs */ for(k = 0; k < dd; k++) { Ptmp = P[ k+1 ] + P[ k ]; Qtmp = Q[ k+1 ] - Q[ k ]; /* the Ptmp and Qtmp values at this stage need to fit in int32 */ a32_QA1[ k ] = -Qtmp - Ptmp; /* QA+1 */ a32_QA1[ d-k-1 ] = Qtmp - Ptmp; /* QA+1 */ } /* Limit the maximum absolute value of the prediction coefficients, so that they'll fit in int16 */ for(i = 0; i < 10; i++) { /* Find maximum absolute value and its index */ maxabs = 0; for(k = 0; k < d; k++) { absval = silk_abs(a32_QA1[k]); if(absval > maxabs) { maxabs = absval; idx = k; } } maxabs = silk_RSHIFT_ROUND(maxabs, QA + 1 - 12); /* QA+1 -> Q12 */ if(maxabs > silk_int16_MAX) { /* Reduce magnitude of prediction coefficients */ maxabs = silk_min(maxabs, 163838); /* (silk_int32_MAX >> 14) + silk_int16_MAX = 163838 */ sc_Q16 = SILK_FIX_CONST(0.999, 16) - silk_DIV32(silk_LSHIFT(maxabs - silk_int16_MAX, 14), silk_RSHIFT32(silk_MUL(maxabs, idx + 1), 2)); silk_bwexpander_32(a32_QA1, d, sc_Q16); } else { break; } } if(i == 10) { /* Reached the last iteration, clip the coefficients */ for(k = 0; k < d; k++) { a_Q12[ k ] = (opus_int16)silk_SAT16(silk_RSHIFT_ROUND(a32_QA1[ k ], QA + 1 - 12)); /* QA+1 -> Q12 */ a32_QA1[ k ] = silk_LSHIFT((opus_int32)a_Q12[ k ], QA + 1 - 12); } } else { for(k = 0; k < d; k++) { a_Q12[ k ] = (opus_int16)silk_RSHIFT_ROUND(a32_QA1[ k ], QA + 1 - 12); /* QA+1 -> Q12 */ } } for(i = 0; i < MAX_LPC_STABILIZE_ITERATIONS; i++) { if(silk_LPC_inverse_pred_gain(a_Q12, d) < SILK_FIX_CONST(1.0 / MAX_PREDICTION_POWER_GAIN, 30)) { /* Prediction coefficients are (too close to) unstable; apply bandwidth expansion */ /* on the unscaled coefficients, convert to Q12 and measure again */ silk_bwexpander_32(a32_QA1, d, 65536 - silk_LSHIFT(2, i)); for(k = 0; k < d; k++) { a_Q12[ k ] = (opus_int16)silk_RSHIFT_ROUND(a32_QA1[ k ], QA + 1 - 12); /* QA+1 -> Q12 */ } } else { break; } } }
opus_int silk_encode_frame_FIX( silk_encoder_state_FIX *psEnc, /* I/O Pointer to Silk FIX encoder state */ opus_int32 *pnBytesOut, /* O Pointer to number of payload bytes; */ ec_enc *psRangeEnc, /* I/O compressor data structure */ opus_int condCoding, /* I The type of conditional coding to use */ opus_int maxBits, /* I If > 0: maximum number of output bits */ opus_int useCBR /* I Flag to force constant-bitrate operation */ ) { silk_encoder_control_FIX sEncCtrl; opus_int i, iter, maxIter, found_upper, found_lower, ret = 0; opus_int16 *x_frame; ec_enc sRangeEnc_copy, sRangeEnc_copy2; silk_nsq_state sNSQ_copy, sNSQ_copy2; opus_int32 seed_copy, nBits, nBits_lower, nBits_upper, gainMult_lower, gainMult_upper; opus_int32 gainsID, gainsID_lower, gainsID_upper; opus_int16 gainMult_Q8; opus_int16 ec_prevLagIndex_copy; opus_int ec_prevSignalType_copy; opus_int8 LastGainIndex_copy2; SAVE_STACK; /* This is totally unnecessary but many compilers (including gcc) are too dumb to realise it */ LastGainIndex_copy2 = nBits_lower = nBits_upper = gainMult_lower = gainMult_upper = 0; psEnc->sCmn.indices.Seed = psEnc->sCmn.frameCounter++ & 3; /**************************************************************/ /* Set up Input Pointers, and insert frame in input buffer */ /*************************************************************/ /* start of frame to encode */ x_frame = psEnc->x_buf + psEnc->sCmn.ltp_mem_length; /***************************************/ /* Ensure smooth bandwidth transitions */ /***************************************/ silk_LP_variable_cutoff( &psEnc->sCmn.sLP, psEnc->sCmn.inputBuf + 1, psEnc->sCmn.frame_length ); /*******************************************/ /* Copy new frame to front of input buffer */ /*******************************************/ silk_memcpy( x_frame + LA_SHAPE_MS * psEnc->sCmn.fs_kHz, psEnc->sCmn.inputBuf + 1, psEnc->sCmn.frame_length * sizeof( opus_int16 ) ); if( !psEnc->sCmn.prefillFlag ) { VARDECL( opus_int32, xfw_Q3 ); VARDECL( opus_int16, res_pitch ); VARDECL( opus_uint8, ec_buf_copy ); opus_int16 *res_pitch_frame; ALLOC( res_pitch, psEnc->sCmn.la_pitch + psEnc->sCmn.frame_length + psEnc->sCmn.ltp_mem_length, opus_int16 ); /* start of pitch LPC residual frame */ res_pitch_frame = res_pitch + psEnc->sCmn.ltp_mem_length; /*****************************************/ /* Find pitch lags, initial LPC analysis */ /*****************************************/ silk_find_pitch_lags_FIX( psEnc, &sEncCtrl, res_pitch, x_frame, psEnc->sCmn.arch ); /************************/ /* Noise shape analysis */ /************************/ silk_noise_shape_analysis_FIX( psEnc, &sEncCtrl, res_pitch_frame, x_frame, psEnc->sCmn.arch ); /***************************************************/ /* Find linear prediction coefficients (LPC + LTP) */ /***************************************************/ silk_find_pred_coefs_FIX( psEnc, &sEncCtrl, res_pitch, x_frame, condCoding ); /****************************************/ /* Process gains */ /****************************************/ silk_process_gains_FIX( psEnc, &sEncCtrl, condCoding ); /*****************************************/ /* Prefiltering for noise shaper */ /*****************************************/ ALLOC( xfw_Q3, psEnc->sCmn.frame_length, opus_int32 ); silk_prefilter_FIX( psEnc, &sEncCtrl, xfw_Q3, x_frame ); /****************************************/ /* Low Bitrate Redundant Encoding */ /****************************************/ silk_LBRR_encode_FIX( psEnc, &sEncCtrl, xfw_Q3, condCoding ); /* Loop over quantizer and entropy coding to control bitrate */ maxIter = 6; gainMult_Q8 = SILK_FIX_CONST( 1, 8 ); found_lower = 0; found_upper = 0; gainsID = silk_gains_ID( psEnc->sCmn.indices.GainsIndices, psEnc->sCmn.nb_subfr ); gainsID_lower = -1; gainsID_upper = -1; /* Copy part of the input state */ silk_memcpy( &sRangeEnc_copy, psRangeEnc, sizeof( ec_enc ) ); silk_memcpy( &sNSQ_copy, &psEnc->sCmn.sNSQ, sizeof( silk_nsq_state ) ); seed_copy = psEnc->sCmn.indices.Seed; ec_prevLagIndex_copy = psEnc->sCmn.ec_prevLagIndex; ec_prevSignalType_copy = psEnc->sCmn.ec_prevSignalType; ALLOC( ec_buf_copy, 1275, opus_uint8 ); for( iter = 0; ; iter++ ) { if( gainsID == gainsID_lower ) { nBits = nBits_lower; } else if( gainsID == gainsID_upper ) { nBits = nBits_upper; } else { /* Restore part of the input state */ if( iter > 0 ) { silk_memcpy( psRangeEnc, &sRangeEnc_copy, sizeof( ec_enc ) ); silk_memcpy( &psEnc->sCmn.sNSQ, &sNSQ_copy, sizeof( silk_nsq_state ) ); psEnc->sCmn.indices.Seed = seed_copy; psEnc->sCmn.ec_prevLagIndex = ec_prevLagIndex_copy; psEnc->sCmn.ec_prevSignalType = ec_prevSignalType_copy; } /*****************************************/ /* Noise shaping quantization */ /*****************************************/ if( psEnc->sCmn.nStatesDelayedDecision > 1 || psEnc->sCmn.warping_Q16 > 0 ) { silk_NSQ_del_dec( &psEnc->sCmn, &psEnc->sCmn.sNSQ, &psEnc->sCmn.indices, xfw_Q3, psEnc->sCmn.pulses, sEncCtrl.PredCoef_Q12[ 0 ], sEncCtrl.LTPCoef_Q14, sEncCtrl.AR2_Q13, sEncCtrl.HarmShapeGain_Q14, sEncCtrl.Tilt_Q14, sEncCtrl.LF_shp_Q14, sEncCtrl.Gains_Q16, sEncCtrl.pitchL, sEncCtrl.Lambda_Q10, sEncCtrl.LTP_scale_Q14, psEnc->sCmn.arch ); } else { silk_NSQ( &psEnc->sCmn, &psEnc->sCmn.sNSQ, &psEnc->sCmn.indices, xfw_Q3, psEnc->sCmn.pulses, sEncCtrl.PredCoef_Q12[ 0 ], sEncCtrl.LTPCoef_Q14, sEncCtrl.AR2_Q13, sEncCtrl.HarmShapeGain_Q14, sEncCtrl.Tilt_Q14, sEncCtrl.LF_shp_Q14, sEncCtrl.Gains_Q16, sEncCtrl.pitchL, sEncCtrl.Lambda_Q10, sEncCtrl.LTP_scale_Q14, psEnc->sCmn.arch); } /****************************************/ /* Encode Parameters */ /****************************************/ silk_encode_indices( &psEnc->sCmn, psRangeEnc, psEnc->sCmn.nFramesEncoded, 0, condCoding ); /****************************************/ /* Encode Excitation Signal */ /****************************************/ silk_encode_pulses( psRangeEnc, psEnc->sCmn.indices.signalType, psEnc->sCmn.indices.quantOffsetType, psEnc->sCmn.pulses, psEnc->sCmn.frame_length ); nBits = ec_tell( psRangeEnc ); if( useCBR == 0 && iter == 0 && nBits <= maxBits ) { break; } } if( iter == maxIter ) { if( found_lower && ( gainsID == gainsID_lower || nBits > maxBits ) ) { /* Restore output state from earlier iteration that did meet the bitrate budget */ silk_memcpy( psRangeEnc, &sRangeEnc_copy2, sizeof( ec_enc ) ); silk_assert( sRangeEnc_copy2.offs <= 1275 ); silk_memcpy( psRangeEnc->buf, ec_buf_copy, sRangeEnc_copy2.offs ); silk_memcpy( &psEnc->sCmn.sNSQ, &sNSQ_copy2, sizeof( silk_nsq_state ) ); psEnc->sShape.LastGainIndex = LastGainIndex_copy2; } break; } if( nBits > maxBits ) { if( found_lower == 0 && iter >= 2 ) { /* Adjust the quantizer's rate/distortion tradeoff and discard previous "upper" results */ sEncCtrl.Lambda_Q10 = silk_ADD_RSHIFT32( sEncCtrl.Lambda_Q10, sEncCtrl.Lambda_Q10, 1 ); found_upper = 0; gainsID_upper = -1; } else { found_upper = 1; nBits_upper = nBits; gainMult_upper = gainMult_Q8; gainsID_upper = gainsID; } } else if( nBits < maxBits - 5 ) { found_lower = 1; nBits_lower = nBits; gainMult_lower = gainMult_Q8; if( gainsID != gainsID_lower ) { gainsID_lower = gainsID; /* Copy part of the output state */ silk_memcpy( &sRangeEnc_copy2, psRangeEnc, sizeof( ec_enc ) ); silk_assert( psRangeEnc->offs <= 1275 ); silk_memcpy( ec_buf_copy, psRangeEnc->buf, psRangeEnc->offs ); silk_memcpy( &sNSQ_copy2, &psEnc->sCmn.sNSQ, sizeof( silk_nsq_state ) ); LastGainIndex_copy2 = psEnc->sShape.LastGainIndex; } } else { /* Within 5 bits of budget: close enough */ break; } if( ( found_lower & found_upper ) == 0 ) { /* Adjust gain according to high-rate rate/distortion curve */ opus_int32 gain_factor_Q16; gain_factor_Q16 = silk_log2lin( silk_LSHIFT( nBits - maxBits, 7 ) / psEnc->sCmn.frame_length + SILK_FIX_CONST( 16, 7 ) ); gain_factor_Q16 = silk_min_32( gain_factor_Q16, SILK_FIX_CONST( 2, 16 ) ); if( nBits > maxBits ) { gain_factor_Q16 = silk_max_32( gain_factor_Q16, SILK_FIX_CONST( 1.3, 16 ) ); } gainMult_Q8 = silk_SMULWB( gain_factor_Q16, gainMult_Q8 ); } else { /* Adjust gain by interpolating */ gainMult_Q8 = gainMult_lower + silk_DIV32_16( silk_MUL( gainMult_upper - gainMult_lower, maxBits - nBits_lower ), nBits_upper - nBits_lower ); /* New gain multplier must be between 25% and 75% of old range (note that gainMult_upper < gainMult_lower) */ if( gainMult_Q8 > silk_ADD_RSHIFT32( gainMult_lower, gainMult_upper - gainMult_lower, 2 ) ) { gainMult_Q8 = silk_ADD_RSHIFT32( gainMult_lower, gainMult_upper - gainMult_lower, 2 ); } else if( gainMult_Q8 < silk_SUB_RSHIFT32( gainMult_upper, gainMult_upper - gainMult_lower, 2 ) ) { gainMult_Q8 = silk_SUB_RSHIFT32( gainMult_upper, gainMult_upper - gainMult_lower, 2 ); } } for( i = 0; i < psEnc->sCmn.nb_subfr; i++ ) { sEncCtrl.Gains_Q16[ i ] = silk_LSHIFT_SAT32( silk_SMULWB( sEncCtrl.GainsUnq_Q16[ i ], gainMult_Q8 ), 8 ); } /* Quantize gains */ psEnc->sShape.LastGainIndex = sEncCtrl.lastGainIndexPrev; silk_gains_quant( psEnc->sCmn.indices.GainsIndices, sEncCtrl.Gains_Q16, &psEnc->sShape.LastGainIndex, condCoding == CODE_CONDITIONALLY, psEnc->sCmn.nb_subfr ); /* Unique identifier of gains vector */ gainsID = silk_gains_ID( psEnc->sCmn.indices.GainsIndices, psEnc->sCmn.nb_subfr ); } } /* Update input buffer */ silk_memmove( psEnc->x_buf, &psEnc->x_buf[ psEnc->sCmn.frame_length ], ( psEnc->sCmn.ltp_mem_length + LA_SHAPE_MS * psEnc->sCmn.fs_kHz ) * sizeof( opus_int16 ) ); /* Exit without entropy coding */ if( psEnc->sCmn.prefillFlag ) { /* No payload */ *pnBytesOut = 0; RESTORE_STACK; return ret; } /* Parameters needed for next frame */ psEnc->sCmn.prevLag = sEncCtrl.pitchL[ psEnc->sCmn.nb_subfr - 1 ]; psEnc->sCmn.prevSignalType = psEnc->sCmn.indices.signalType; /****************************************/ /* Finalize payload */ /****************************************/ psEnc->sCmn.first_frame_after_reset = 0; /* Payload size */ *pnBytesOut = silk_RSHIFT( ec_tell( psRangeEnc ) + 7, 3 ); RESTORE_STACK; return ret; }
/* Decode side-information parameters from payload */ void silk_decode_indices(silk_decoder_state * psDec, /* I/O State */ ec_dec * psRangeDec, /* I/O Compressor data structure */ int FrameIndex, /* I Frame number */ int decode_LBRR, /* I Flag indicating LBRR data is being decoded */ int condCoding /* I The type of conditional coding to use */ ) { int i, k, Ix; int decode_absolute_lagIndex, delta_lagIndex; int16_t ec_ix[MAX_LPC_ORDER]; uint8_t pred_Q8[MAX_LPC_ORDER]; /*******************************************/ /* Decode signal type and quantizer offset */ /*******************************************/ if (decode_LBRR || psDec->VAD_flags[FrameIndex]) { Ix = ec_dec_icdf(psRangeDec, silk_type_offset_VAD_iCDF, 8) + 2; } else { Ix = ec_dec_icdf(psRangeDec, silk_type_offset_no_VAD_iCDF, 8); } psDec->indices.signalType = (int8_t) silk_RSHIFT(Ix, 1); psDec->indices.quantOffsetType = (int8_t) (Ix & 1); /****************/ /* Decode gains */ /****************/ /* First subframe */ if (condCoding == CODE_CONDITIONALLY) { /* Conditional coding */ psDec->indices.GainsIndices[0] = (int8_t) ec_dec_icdf(psRangeDec, silk_delta_gain_iCDF, 8); } else { /* Independent coding, in two stages: MSB bits followed by 3 LSBs */ psDec->indices.GainsIndices[0] = (int8_t) silk_LSHIFT(ec_dec_icdf (psRangeDec, silk_gain_iCDF[psDec->indices.signalType], 8), 3); psDec->indices.GainsIndices[0] += (int8_t) ec_dec_icdf(psRangeDec, silk_uniform8_iCDF, 8); } /* Remaining subframes */ for (i = 1; i < psDec->nb_subfr; i++) { psDec->indices.GainsIndices[i] = (int8_t) ec_dec_icdf(psRangeDec, silk_delta_gain_iCDF, 8); } /**********************/ /* Decode LSF Indices */ /**********************/ psDec->indices.NLSFIndices[0] = (int8_t) ec_dec_icdf(psRangeDec, &psDec->psNLSF_CB-> CB1_iCDF[(psDec->indices.signalType >> 1) * psDec->psNLSF_CB->nVectors], 8); silk_NLSF_unpack(ec_ix, pred_Q8, psDec->psNLSF_CB, psDec->indices.NLSFIndices[0]); assert(psDec->psNLSF_CB->order == psDec->LPC_order); for (i = 0; i < psDec->psNLSF_CB->order; i++) { Ix = ec_dec_icdf(psRangeDec, &psDec->psNLSF_CB->ec_iCDF[ec_ix[i]], 8); if (Ix == 0) { Ix -= ec_dec_icdf(psRangeDec, silk_NLSF_EXT_iCDF, 8); } else if (Ix == 2 * NLSF_QUANT_MAX_AMPLITUDE) { Ix += ec_dec_icdf(psRangeDec, silk_NLSF_EXT_iCDF, 8); } psDec->indices.NLSFIndices[i + 1] = (int8_t) (Ix - NLSF_QUANT_MAX_AMPLITUDE); } /* Decode LSF interpolation factor */ if (psDec->nb_subfr == MAX_NB_SUBFR) { psDec->indices.NLSFInterpCoef_Q2 = (int8_t) ec_dec_icdf(psRangeDec, silk_NLSF_interpolation_factor_iCDF, 8); } else { psDec->indices.NLSFInterpCoef_Q2 = 4; } if (psDec->indices.signalType == TYPE_VOICED) { /*********************/ /* Decode pitch lags */ /*********************/ /* Get lag index */ decode_absolute_lagIndex = 1; if (condCoding == CODE_CONDITIONALLY && psDec->ec_prevSignalType == TYPE_VOICED) { /* Decode Delta index */ delta_lagIndex = (int16_t) ec_dec_icdf(psRangeDec, silk_pitch_delta_iCDF, 8); if (delta_lagIndex > 0) { delta_lagIndex = delta_lagIndex - 9; psDec->indices.lagIndex = (int16_t) (psDec->ec_prevLagIndex + delta_lagIndex); decode_absolute_lagIndex = 0; } } if (decode_absolute_lagIndex) { /* Absolute decoding */ psDec->indices.lagIndex = (int16_t) ec_dec_icdf(psRangeDec, silk_pitch_lag_iCDF, 8) * silk_RSHIFT(psDec->fs_kHz, 1); psDec->indices.lagIndex += (int16_t) ec_dec_icdf(psRangeDec, psDec-> pitch_lag_low_bits_iCDF, 8); } psDec->ec_prevLagIndex = psDec->indices.lagIndex; /* Get countour index */ psDec->indices.contourIndex = (int8_t) ec_dec_icdf(psRangeDec, psDec->pitch_contour_iCDF, 8); /********************/ /* Decode LTP gains */ /********************/ /* Decode PERIndex value */ psDec->indices.PERIndex = (int8_t) ec_dec_icdf(psRangeDec, silk_LTP_per_index_iCDF, 8); for (k = 0; k < psDec->nb_subfr; k++) { psDec->indices.LTPIndex[k] = (int8_t) ec_dec_icdf(psRangeDec, silk_LTP_gain_iCDF_ptrs [psDec->indices.PERIndex], 8); } /**********************/ /* Decode LTP scaling */ /**********************/ if (condCoding == CODE_INDEPENDENTLY) { psDec->indices.LTP_scaleIndex = (int8_t) ec_dec_icdf(psRangeDec, silk_LTPscale_iCDF, 8); } else { psDec->indices.LTP_scaleIndex = 0; } } psDec->ec_prevSignalType = psDec->indices.signalType; /***************/ /* Decode seed */ /***************/ psDec->indices.Seed = (int8_t) ec_dec_icdf(psRangeDec, silk_uniform4_iCDF, 8); }
void silk_decode_pulses( ec_dec *psRangeDec, /* I/O Compressor data structure */ opus_int pulses[], /* O Excitation signal */ const opus_int signalType, /* I Sigtype */ const opus_int quantOffsetType, /* I quantOffsetType */ const opus_int frame_length /* I Frame length */ ) { opus_int i, j, k, iter, abs_q, nLS, RateLevelIndex; opus_int sum_pulses[ MAX_NB_SHELL_BLOCKS ], nLshifts[ MAX_NB_SHELL_BLOCKS ]; opus_int *pulses_ptr; const opus_uint8 *cdf_ptr; /*********************/ /* Decode rate level */ /*********************/ RateLevelIndex = ec_dec_icdf( psRangeDec, silk_rate_levels_iCDF[ signalType >> 1 ], 8 ); /* Calculate number of shell blocks */ silk_assert( 1 << LOG2_SHELL_CODEC_FRAME_LENGTH == SHELL_CODEC_FRAME_LENGTH ); iter = silk_RSHIFT( frame_length, LOG2_SHELL_CODEC_FRAME_LENGTH ); if( iter * SHELL_CODEC_FRAME_LENGTH < frame_length ) { silk_assert( frame_length == 12 * 10 ); /* Make sure only happens for 10 ms @ 12 kHz */ iter++; } /***************************************************/ /* Sum-Weighted-Pulses Decoding */ /***************************************************/ cdf_ptr = silk_pulses_per_block_iCDF[ RateLevelIndex ]; for( i = 0; i < iter; i++ ) { nLshifts[ i ] = 0; sum_pulses[ i ] = ec_dec_icdf( psRangeDec, cdf_ptr, 8 ); /* LSB indication */ while( sum_pulses[ i ] == MAX_PULSES + 1 ) { nLshifts[ i ]++; /* When we've already got 10 LSBs, we shift the table to not allow (MAX_PULSES + 1) */ sum_pulses[ i ] = ec_dec_icdf( psRangeDec, silk_pulses_per_block_iCDF[ N_RATE_LEVELS - 1] + ( nLshifts[ i ] == 10 ), 8 ); } } /***************************************************/ /* Shell decoding */ /***************************************************/ for( i = 0; i < iter; i++ ) { if( sum_pulses[ i ] > 0 ) { silk_shell_decoder( &pulses[ silk_SMULBB( i, SHELL_CODEC_FRAME_LENGTH ) ], psRangeDec, sum_pulses[ i ] ); } else { silk_memset( &pulses[ silk_SMULBB( i, SHELL_CODEC_FRAME_LENGTH ) ], 0, SHELL_CODEC_FRAME_LENGTH * sizeof( opus_int ) ); } } /***************************************************/ /* LSB Decoding */ /***************************************************/ for( i = 0; i < iter; i++ ) { if( nLshifts[ i ] > 0 ) { nLS = nLshifts[ i ]; pulses_ptr = &pulses[ silk_SMULBB( i, SHELL_CODEC_FRAME_LENGTH ) ]; for( k = 0; k < SHELL_CODEC_FRAME_LENGTH; k++ ) { abs_q = pulses_ptr[ k ]; for( j = 0; j < nLS; j++ ) { abs_q = silk_LSHIFT( abs_q, 1 ); abs_q += ec_dec_icdf( psRangeDec, silk_lsb_iCDF, 8 ); } pulses_ptr[ k ] = abs_q; } /* Mark the number of pulses non-zero for sign decoding. */ sum_pulses[ i ] |= nLS << 5; } } /****************************************/ /* Decode and add signs to pulse signal */ /****************************************/ silk_decode_signs( psRangeDec, pulses, frame_length, signalType, quantOffsetType, sum_pulses ); }
/* Convert Left/Right stereo signal to adaptive Mid/Side representation */ void silk_stereo_LR_to_MS( stereo_enc_state *state, /* I/O State */ opus_int16 x1[], /* I/O Left input signal, becomes mid signal */ opus_int16 x2[], /* I/O Right input signal, becomes side signal */ opus_int8 ix[ 2 ][ 3 ], /* O Quantization indices */ opus_int8 *mid_only_flag, /* O Flag: only mid signal coded */ opus_int32 mid_side_rates_bps[], /* O Bitrates for mid and side signals */ opus_int32 total_rate_bps, /* I Total bitrate */ opus_int prev_speech_act_Q8, /* I Speech activity level in previous frame */ opus_int toMono, /* I Last frame before a stereo->mono transition */ opus_int fs_kHz, /* I Sample rate (kHz) */ opus_int frame_length /* I Number of samples */ ) { opus_int n, is10msFrame, denom_Q16, delta0_Q13, delta1_Q13; opus_int32 sum, diff, smooth_coef_Q16, pred_Q13[ 2 ], pred0_Q13, pred1_Q13; opus_int32 LP_ratio_Q14, HP_ratio_Q14, frac_Q16, frac_3_Q16, min_mid_rate_bps, width_Q14, w_Q24, deltaw_Q24; VARDECL( opus_int16, side ); VARDECL( opus_int16, LP_mid ); VARDECL( opus_int16, HP_mid ); VARDECL( opus_int16, LP_side ); VARDECL( opus_int16, HP_side ); opus_int16 *mid = &x1[ -2 ]; SAVE_STACK; ALLOC( side, frame_length + 2, opus_int16 ); /* Convert to basic mid/side signals */ for( n = 0; n < frame_length + 2; n++ ) { sum = x1[ n - 2 ] + (opus_int32)x2[ n - 2 ]; diff = x1[ n - 2 ] - (opus_int32)x2[ n - 2 ]; mid[ n ] = (opus_int16)silk_RSHIFT_ROUND( sum, 1 ); side[ n ] = (opus_int16)silk_SAT16( silk_RSHIFT_ROUND( diff, 1 ) ); } /* Buffering */ silk_memcpy( mid, state->sMid, 2 * sizeof( opus_int16 ) ); silk_memcpy( side, state->sSide, 2 * sizeof( opus_int16 ) ); silk_memcpy( state->sMid, &mid[ frame_length ], 2 * sizeof( opus_int16 ) ); silk_memcpy( state->sSide, &side[ frame_length ], 2 * sizeof( opus_int16 ) ); /* LP and HP filter mid signal */ ALLOC( LP_mid, frame_length, opus_int16 ); ALLOC( HP_mid, frame_length, opus_int16 ); for( n = 0; n < frame_length; n++ ) { sum = silk_RSHIFT_ROUND( silk_ADD_LSHIFT( mid[ n ] + mid[ n + 2 ], mid[ n + 1 ], 1 ), 2 ); LP_mid[ n ] = sum; HP_mid[ n ] = mid[ n + 1 ] - sum; } /* LP and HP filter side signal */ ALLOC( LP_side, frame_length, opus_int16 ); ALLOC( HP_side, frame_length, opus_int16 ); for( n = 0; n < frame_length; n++ ) { sum = silk_RSHIFT_ROUND( silk_ADD_LSHIFT( side[ n ] + side[ n + 2 ], side[ n + 1 ], 1 ), 2 ); LP_side[ n ] = sum; HP_side[ n ] = side[ n + 1 ] - sum; } /* Find energies and predictors */ is10msFrame = frame_length == 10 * fs_kHz; smooth_coef_Q16 = is10msFrame ? SILK_FIX_CONST( STEREO_RATIO_SMOOTH_COEF / 2, 16 ) : SILK_FIX_CONST( STEREO_RATIO_SMOOTH_COEF, 16 ); smooth_coef_Q16 = silk_SMULWB( silk_SMULBB( prev_speech_act_Q8, prev_speech_act_Q8 ), smooth_coef_Q16 ); pred_Q13[ 0 ] = silk_stereo_find_predictor( &LP_ratio_Q14, LP_mid, LP_side, &state->mid_side_amp_Q0[ 0 ], frame_length, smooth_coef_Q16 ); pred_Q13[ 1 ] = silk_stereo_find_predictor( &HP_ratio_Q14, HP_mid, HP_side, &state->mid_side_amp_Q0[ 2 ], frame_length, smooth_coef_Q16 ); /* Ratio of the norms of residual and mid signals */ frac_Q16 = silk_SMLABB( HP_ratio_Q14, LP_ratio_Q14, 3 ); frac_Q16 = silk_min( frac_Q16, SILK_FIX_CONST( 1, 16 ) ); /* Determine bitrate distribution between mid and side, and possibly reduce stereo width */ total_rate_bps -= is10msFrame ? 1200 : 600; /* Subtract approximate bitrate for coding stereo parameters */ if( total_rate_bps < 1 ) { total_rate_bps = 1; } min_mid_rate_bps = silk_SMLABB( 2000, fs_kHz, 900 ); silk_assert( min_mid_rate_bps < 32767 ); /* Default bitrate distribution: 8 parts for Mid and (5+3*frac) parts for Side. so: mid_rate = ( 8 / ( 13 + 3 * frac ) ) * total_ rate */ frac_3_Q16 = silk_MUL( 3, frac_Q16 ); mid_side_rates_bps[ 0 ] = silk_DIV32_varQ( total_rate_bps, SILK_FIX_CONST( 8 + 5, 16 ) + frac_3_Q16, 16+3 ); /* If Mid bitrate below minimum, reduce stereo width */ if( mid_side_rates_bps[ 0 ] < min_mid_rate_bps ) { mid_side_rates_bps[ 0 ] = min_mid_rate_bps; mid_side_rates_bps[ 1 ] = total_rate_bps - mid_side_rates_bps[ 0 ]; /* width = 4 * ( 2 * side_rate - min_rate ) / ( ( 1 + 3 * frac ) * min_rate ) */ width_Q14 = silk_DIV32_varQ( silk_LSHIFT( mid_side_rates_bps[ 1 ], 1 ) - min_mid_rate_bps, silk_SMULWB( SILK_FIX_CONST( 1, 16 ) + frac_3_Q16, min_mid_rate_bps ), 14+2 ); width_Q14 = silk_LIMIT( width_Q14, 0, SILK_FIX_CONST( 1, 14 ) ); } else { mid_side_rates_bps[ 1 ] = total_rate_bps - mid_side_rates_bps[ 0 ]; width_Q14 = SILK_FIX_CONST( 1, 14 ); } /* Smoother */ state->smth_width_Q14 = (opus_int16)silk_SMLAWB( state->smth_width_Q14, width_Q14 - state->smth_width_Q14, smooth_coef_Q16 ); /* At very low bitrates or for inputs that are nearly amplitude panned, switch to panned-mono coding */ *mid_only_flag = 0; if( toMono ) { /* Last frame before stereo->mono transition; collapse stereo width */ width_Q14 = 0; pred_Q13[ 0 ] = 0; pred_Q13[ 1 ] = 0; silk_stereo_quant_pred( pred_Q13, ix ); } else if( state->width_prev_Q14 == 0 && ( 8 * total_rate_bps < 13 * min_mid_rate_bps || silk_SMULWB( frac_Q16, state->smth_width_Q14 ) < SILK_FIX_CONST( 0.05, 14 ) ) ) { /* Code as panned-mono; previous frame already had zero width */ /* Scale down and quantize predictors */ pred_Q13[ 0 ] = silk_RSHIFT( silk_SMULBB( state->smth_width_Q14, pred_Q13[ 0 ] ), 14 ); pred_Q13[ 1 ] = silk_RSHIFT( silk_SMULBB( state->smth_width_Q14, pred_Q13[ 1 ] ), 14 ); silk_stereo_quant_pred( pred_Q13, ix ); /* Collapse stereo width */ width_Q14 = 0; pred_Q13[ 0 ] = 0; pred_Q13[ 1 ] = 0; mid_side_rates_bps[ 0 ] = total_rate_bps; mid_side_rates_bps[ 1 ] = 0; *mid_only_flag = 1; } else if( state->width_prev_Q14 != 0 && ( 8 * total_rate_bps < 11 * min_mid_rate_bps || silk_SMULWB( frac_Q16, state->smth_width_Q14 ) < SILK_FIX_CONST( 0.02, 14 ) ) ) { /* Transition to zero-width stereo */ /* Scale down and quantize predictors */ pred_Q13[ 0 ] = silk_RSHIFT( silk_SMULBB( state->smth_width_Q14, pred_Q13[ 0 ] ), 14 ); pred_Q13[ 1 ] = silk_RSHIFT( silk_SMULBB( state->smth_width_Q14, pred_Q13[ 1 ] ), 14 ); silk_stereo_quant_pred( pred_Q13, ix ); /* Collapse stereo width */ width_Q14 = 0; pred_Q13[ 0 ] = 0; pred_Q13[ 1 ] = 0; } else if( state->smth_width_Q14 > SILK_FIX_CONST( 0.95, 14 ) ) { /* Full-width stereo coding */ silk_stereo_quant_pred( pred_Q13, ix ); width_Q14 = SILK_FIX_CONST( 1, 14 ); } else { /* Reduced-width stereo coding; scale down and quantize predictors */ pred_Q13[ 0 ] = silk_RSHIFT( silk_SMULBB( state->smth_width_Q14, pred_Q13[ 0 ] ), 14 ); pred_Q13[ 1 ] = silk_RSHIFT( silk_SMULBB( state->smth_width_Q14, pred_Q13[ 1 ] ), 14 ); silk_stereo_quant_pred( pred_Q13, ix ); width_Q14 = state->smth_width_Q14; } /* Make sure to keep on encoding until the tapered output has been transmitted */ if( *mid_only_flag == 1 ) { state->silent_side_len += frame_length - STEREO_INTERP_LEN_MS * fs_kHz; if( state->silent_side_len < LA_SHAPE_MS * fs_kHz ) { *mid_only_flag = 0; } else { /* Limit to avoid wrapping around */ state->silent_side_len = 10000; } } else { state->silent_side_len = 0; } if( *mid_only_flag == 0 && mid_side_rates_bps[ 1 ] < 1 ) { mid_side_rates_bps[ 1 ] = 1; mid_side_rates_bps[ 0 ] = silk_max_int( 1, total_rate_bps - mid_side_rates_bps[ 1 ]); } /* Interpolate predictors and subtract prediction from side channel */ pred0_Q13 = -state->pred_prev_Q13[ 0 ]; pred1_Q13 = -state->pred_prev_Q13[ 1 ]; w_Q24 = silk_LSHIFT( state->width_prev_Q14, 10 ); denom_Q16 = silk_DIV32_16( (opus_int32)1 << 16, STEREO_INTERP_LEN_MS * fs_kHz ); delta0_Q13 = -silk_RSHIFT_ROUND( silk_SMULBB( pred_Q13[ 0 ] - state->pred_prev_Q13[ 0 ], denom_Q16 ), 16 ); delta1_Q13 = -silk_RSHIFT_ROUND( silk_SMULBB( pred_Q13[ 1 ] - state->pred_prev_Q13[ 1 ], denom_Q16 ), 16 ); deltaw_Q24 = silk_LSHIFT( silk_SMULWB( width_Q14 - state->width_prev_Q14, denom_Q16 ), 10 ); for( n = 0; n < STEREO_INTERP_LEN_MS * fs_kHz; n++ ) { pred0_Q13 += delta0_Q13; pred1_Q13 += delta1_Q13; w_Q24 += deltaw_Q24; sum = silk_LSHIFT( silk_ADD_LSHIFT( mid[ n ] + mid[ n + 2 ], mid[ n + 1 ], 1 ), 9 ); /* Q11 */ sum = silk_SMLAWB( silk_SMULWB( w_Q24, side[ n + 1 ] ), sum, pred0_Q13 ); /* Q8 */ sum = silk_SMLAWB( sum, silk_LSHIFT( (opus_int32)mid[ n + 1 ], 11 ), pred1_Q13 ); /* Q8 */ x2[ n - 1 ] = (opus_int16)silk_SAT16( silk_RSHIFT_ROUND( sum, 8 ) ); } pred0_Q13 = -pred_Q13[ 0 ]; pred1_Q13 = -pred_Q13[ 1 ]; w_Q24 = silk_LSHIFT( width_Q14, 10 ); for( n = STEREO_INTERP_LEN_MS * fs_kHz; n < frame_length; n++ ) { sum = silk_LSHIFT( silk_ADD_LSHIFT( mid[ n ] + mid[ n + 2 ], mid[ n + 1 ], 1 ), 9 ); /* Q11 */ sum = silk_SMLAWB( silk_SMULWB( w_Q24, side[ n + 1 ] ), sum, pred0_Q13 ); /* Q8 */ sum = silk_SMLAWB( sum, silk_LSHIFT( (opus_int32)mid[ n + 1 ], 11 ), pred1_Q13 ); /* Q8 */ x2[ n - 1 ] = (opus_int16)silk_SAT16( silk_RSHIFT_ROUND( sum, 8 ) ); } state->pred_prev_Q13[ 0 ] = (opus_int16)pred_Q13[ 0 ]; state->pred_prev_Q13[ 1 ] = (opus_int16)pred_Q13[ 1 ]; state->width_prev_Q14 = (opus_int16)width_Q14; RESTORE_STACK; }
opus_int silk_VAD_GetSA_Q8( /* O Return value, 0 if success */ silk_encoder_state *psEncC, /* I/O Encoder state */ const opus_int16 pIn[] /* I PCM input */ ) { opus_int SA_Q15, pSNR_dB_Q7, input_tilt; opus_int decimated_framelength, dec_subframe_length, dec_subframe_offset, SNR_Q7, i, b, s; opus_int32 sumSquared, smooth_coef_Q16; opus_int16 HPstateTmp; opus_int16 X[ VAD_N_BANDS ][ MAX_FRAME_LENGTH / 2 ]; opus_int32 Xnrg[ VAD_N_BANDS ]; opus_int32 NrgToNoiseRatio_Q8[ VAD_N_BANDS ]; opus_int32 speech_nrg, x_tmp; opus_int ret = 0; silk_VAD_state *psSilk_VAD = &psEncC->sVAD; /* Safety checks */ silk_assert( VAD_N_BANDS == 4 ); silk_assert( MAX_FRAME_LENGTH >= psEncC->frame_length ); silk_assert( psEncC->frame_length <= 512 ); silk_assert( psEncC->frame_length == 8 * silk_RSHIFT( psEncC->frame_length, 3 ) ); /***********************/ /* Filter and Decimate */ /***********************/ /* 0-8 kHz to 0-4 kHz and 4-8 kHz */ silk_ana_filt_bank_1( pIn, &psSilk_VAD->AnaState[ 0 ], &X[ 0 ][ 0 ], &X[ 3 ][ 0 ], psEncC->frame_length ); /* 0-4 kHz to 0-2 kHz and 2-4 kHz */ silk_ana_filt_bank_1( &X[ 0 ][ 0 ], &psSilk_VAD->AnaState1[ 0 ], &X[ 0 ][ 0 ], &X[ 2 ][ 0 ], silk_RSHIFT( psEncC->frame_length, 1 ) ); /* 0-2 kHz to 0-1 kHz and 1-2 kHz */ silk_ana_filt_bank_1( &X[ 0 ][ 0 ], &psSilk_VAD->AnaState2[ 0 ], &X[ 0 ][ 0 ], &X[ 1 ][ 0 ], silk_RSHIFT( psEncC->frame_length, 2 ) ); /*********************************************/ /* HP filter on lowest band (differentiator) */ /*********************************************/ decimated_framelength = silk_RSHIFT( psEncC->frame_length, 3 ); X[ 0 ][ decimated_framelength - 1 ] = silk_RSHIFT( X[ 0 ][ decimated_framelength - 1 ], 1 ); HPstateTmp = X[ 0 ][ decimated_framelength - 1 ]; for( i = decimated_framelength - 1; i > 0; i-- ) { X[ 0 ][ i - 1 ] = silk_RSHIFT( X[ 0 ][ i - 1 ], 1 ); X[ 0 ][ i ] -= X[ 0 ][ i - 1 ]; } X[ 0 ][ 0 ] -= psSilk_VAD->HPstate; psSilk_VAD->HPstate = HPstateTmp; /*************************************/ /* Calculate the energy in each band */ /*************************************/ for( b = 0; b < VAD_N_BANDS; b++ ) { /* Find the decimated framelength in the non-uniformly divided bands */ decimated_framelength = silk_RSHIFT( psEncC->frame_length, silk_min_int( VAD_N_BANDS - b, VAD_N_BANDS - 1 ) ); /* Split length into subframe lengths */ dec_subframe_length = silk_RSHIFT( decimated_framelength, VAD_INTERNAL_SUBFRAMES_LOG2 ); dec_subframe_offset = 0; /* Compute energy per sub-frame */ /* initialize with summed energy of last subframe */ Xnrg[ b ] = psSilk_VAD->XnrgSubfr[ b ]; for( s = 0; s < VAD_INTERNAL_SUBFRAMES; s++ ) { sumSquared = 0; for( i = 0; i < dec_subframe_length; i++ ) { /* The energy will be less than dec_subframe_length * ( silk_int16_MIN / 8 ) ^ 2. */ /* Therefore we can accumulate with no risk of overflow (unless dec_subframe_length > 128) */ x_tmp = silk_RSHIFT( X[ b ][ i + dec_subframe_offset ], 3 ); sumSquared = silk_SMLABB( sumSquared, x_tmp, x_tmp ); /* Safety check */ silk_assert( sumSquared >= 0 ); } /* Add/saturate summed energy of current subframe */ if( s < VAD_INTERNAL_SUBFRAMES - 1 ) { Xnrg[ b ] = silk_ADD_POS_SAT32( Xnrg[ b ], sumSquared ); } else { /* Look-ahead subframe */ Xnrg[ b ] = silk_ADD_POS_SAT32( Xnrg[ b ], silk_RSHIFT( sumSquared, 1 ) ); } dec_subframe_offset += dec_subframe_length; } psSilk_VAD->XnrgSubfr[ b ] = sumSquared; } /********************/ /* Noise estimation */ /********************/ silk_VAD_GetNoiseLevels( &Xnrg[ 0 ], psSilk_VAD ); /***********************************************/ /* Signal-plus-noise to noise ratio estimation */ /***********************************************/ sumSquared = 0; input_tilt = 0; for( b = 0; b < VAD_N_BANDS; b++ ) { speech_nrg = Xnrg[ b ] - psSilk_VAD->NL[ b ]; if( speech_nrg > 0 ) { /* Divide, with sufficient resolution */ if( ( Xnrg[ b ] & 0xFF800000 ) == 0 ) { NrgToNoiseRatio_Q8[ b ] = silk_DIV32( silk_LSHIFT( Xnrg[ b ], 8 ), psSilk_VAD->NL[ b ] + 1 ); } else { NrgToNoiseRatio_Q8[ b ] = silk_DIV32( Xnrg[ b ], silk_RSHIFT( psSilk_VAD->NL[ b ], 8 ) + 1 ); } /* Convert to log domain */ SNR_Q7 = silk_lin2log( NrgToNoiseRatio_Q8[ b ] ) - 8 * 128; /* Sum-of-squares */ sumSquared = silk_SMLABB( sumSquared, SNR_Q7, SNR_Q7 ); /* Q14 */ /* Tilt measure */ if( speech_nrg < ( (opus_int32)1 << 20 ) ) { /* Scale down SNR value for small subband speech energies */ SNR_Q7 = silk_SMULWB( silk_LSHIFT( silk_SQRT_APPROX( speech_nrg ), 6 ), SNR_Q7 ); } input_tilt = silk_SMLAWB( input_tilt, tiltWeights[ b ], SNR_Q7 ); } else { NrgToNoiseRatio_Q8[ b ] = 256; } } /* Mean-of-squares */ sumSquared = silk_DIV32_16( sumSquared, VAD_N_BANDS ); /* Q14 */ /* Root-mean-square approximation, scale to dBs, and write to output pointer */ pSNR_dB_Q7 = (opus_int16)( 3 * silk_SQRT_APPROX( sumSquared ) ); /* Q7 */ /*********************************/ /* Speech Probability Estimation */ /*********************************/ SA_Q15 = silk_sigm_Q15( silk_SMULWB( VAD_SNR_FACTOR_Q16, pSNR_dB_Q7 ) - VAD_NEGATIVE_OFFSET_Q5 ); /**************************/ /* Frequency Tilt Measure */ /**************************/ psEncC->input_tilt_Q15 = silk_LSHIFT( silk_sigm_Q15( input_tilt ) - 16384, 1 ); /**************************************************/ /* Scale the sigmoid output based on power levels */ /**************************************************/ speech_nrg = 0; for( b = 0; b < VAD_N_BANDS; b++ ) { /* Accumulate signal-without-noise energies, higher frequency bands have more weight */ speech_nrg += ( b + 1 ) * silk_RSHIFT( Xnrg[ b ] - psSilk_VAD->NL[ b ], 4 ); } /* Power scaling */ if( speech_nrg <= 0 ) { SA_Q15 = silk_RSHIFT( SA_Q15, 1 ); } else if( speech_nrg < 32768 ) { if( psEncC->frame_length == 10 * psEncC->fs_kHz ) { speech_nrg = silk_LSHIFT_SAT32( speech_nrg, 16 ); } else { speech_nrg = silk_LSHIFT_SAT32( speech_nrg, 15 ); } /* square-root */ speech_nrg = silk_SQRT_APPROX( speech_nrg ); SA_Q15 = silk_SMULWB( 32768 + speech_nrg, SA_Q15 ); } /* Copy the resulting speech activity in Q8 */ psEncC->speech_activity_Q8 = silk_min_int( silk_RSHIFT( SA_Q15, 7 ), silk_uint8_MAX ); /***********************************/ /* Energy Level and SNR estimation */ /***********************************/ /* Smoothing coefficient */ smooth_coef_Q16 = silk_SMULWB( VAD_SNR_SMOOTH_COEF_Q18, silk_SMULWB( (opus_int32)SA_Q15, SA_Q15 ) ); if( psEncC->frame_length == 10 * psEncC->fs_kHz ) { smooth_coef_Q16 >>= 1; }
opus_int silk_encode_frame_FLP( silk_encoder_state_FLP *psEnc, /* I/O Encoder state FLP */ opus_int32 *pnBytesOut, /* O Number of payload bytes; */ ec_enc *psRangeEnc, /* I/O compressor data structure */ opus_int condCoding, /* I The type of conditional coding to use */ opus_int maxBits, /* I If > 0: maximum number of output bits */ opus_int useCBR /* I Flag to force constant-bitrate operation */ ) { silk_encoder_control_FLP sEncCtrl; opus_int i, iter, maxIter, found_upper, found_lower, ret = 0; silk_float *x_frame, *res_pitch_frame; silk_float xfw[ MAX_FRAME_LENGTH ]; silk_float res_pitch[ 2 * MAX_FRAME_LENGTH + LA_PITCH_MAX ]; ec_enc sRangeEnc_copy, sRangeEnc_copy2; silk_nsq_state sNSQ_copy, sNSQ_copy2; opus_int32 seed_copy, nBits, nBits_lower, nBits_upper, gainMult_lower, gainMult_upper; opus_int32 gainsID, gainsID_lower, gainsID_upper; opus_int16 gainMult_Q8; opus_int16 ec_prevLagIndex_copy; opus_int ec_prevSignalType_copy; opus_int8 LastGainIndex_copy2; opus_int32 pGains_Q16[ MAX_NB_SUBFR ]; opus_uint8 ec_buf_copy[ 1275 ]; /* This is totally unnecessary but many compilers (including gcc) are too dumb to realise it */ LastGainIndex_copy2 = nBits_lower = nBits_upper = gainMult_lower = gainMult_upper = 0; psEnc->sCmn.indices.Seed = psEnc->sCmn.frameCounter++ & 3; /**************************************************************/ /* Set up Input Pointers, and insert frame in input buffer */ /**************************************************************/ /* pointers aligned with start of frame to encode */ x_frame = psEnc->x_buf + psEnc->sCmn.ltp_mem_length; /* start of frame to encode */ res_pitch_frame = res_pitch + psEnc->sCmn.ltp_mem_length; /* start of pitch LPC residual frame */ /***************************************/ /* Ensure smooth bandwidth transitions */ /***************************************/ silk_LP_variable_cutoff( &psEnc->sCmn.sLP, psEnc->sCmn.inputBuf + 1, psEnc->sCmn.frame_length ); /*******************************************/ /* Copy new frame to front of input buffer */ /*******************************************/ silk_short2float_array( x_frame + LA_SHAPE_MS * psEnc->sCmn.fs_kHz, psEnc->sCmn.inputBuf + 1, psEnc->sCmn.frame_length ); /* Add tiny signal to avoid high CPU load from denormalized floating point numbers */ for( i = 0; i < 8; i++ ) { x_frame[ LA_SHAPE_MS * psEnc->sCmn.fs_kHz + i * ( psEnc->sCmn.frame_length >> 3 ) ] += ( 1 - ( i & 2 ) ) * 1e-6f; } if( !psEnc->sCmn.prefillFlag ) { /*****************************************/ /* Find pitch lags, initial LPC analysis */ /*****************************************/ silk_find_pitch_lags_FLP( psEnc, &sEncCtrl, res_pitch, x_frame ); /************************/ /* Noise shape analysis */ /************************/ silk_noise_shape_analysis_FLP( psEnc, &sEncCtrl, res_pitch_frame, x_frame ); /***************************************************/ /* Find linear prediction coefficients (LPC + LTP) */ /***************************************************/ silk_find_pred_coefs_FLP( psEnc, &sEncCtrl, res_pitch, x_frame, condCoding ); /****************************************/ /* Process gains */ /****************************************/ silk_process_gains_FLP( psEnc, &sEncCtrl, condCoding ); /*****************************************/ /* Prefiltering for noise shaper */ /*****************************************/ silk_prefilter_FLP( psEnc, &sEncCtrl, xfw, x_frame ); /****************************************/ /* Low Bitrate Redundant Encoding */ /****************************************/ silk_LBRR_encode_FLP( psEnc, &sEncCtrl, xfw, condCoding ); /* Loop over quantizer and entroy coding to control bitrate */ maxIter = 6; gainMult_Q8 = SILK_FIX_CONST( 1, 8 ); found_lower = 0; found_upper = 0; gainsID = silk_gains_ID( psEnc->sCmn.indices.GainsIndices, psEnc->sCmn.nb_subfr ); gainsID_lower = -1; gainsID_upper = -1; /* Copy part of the input state */ silk_memcpy( &sRangeEnc_copy, psRangeEnc, sizeof( ec_enc ) ); silk_memcpy( &sNSQ_copy, &psEnc->sCmn.sNSQ, sizeof( silk_nsq_state ) ); seed_copy = psEnc->sCmn.indices.Seed; ec_prevLagIndex_copy = psEnc->sCmn.ec_prevLagIndex; ec_prevSignalType_copy = psEnc->sCmn.ec_prevSignalType; for( iter = 0; ; iter++ ) { if( gainsID == gainsID_lower ) { nBits = nBits_lower; } else if( gainsID == gainsID_upper ) { nBits = nBits_upper; } else { /* Restore part of the input state */ if( iter > 0 ) { silk_memcpy( psRangeEnc, &sRangeEnc_copy, sizeof( ec_enc ) ); silk_memcpy( &psEnc->sCmn.sNSQ, &sNSQ_copy, sizeof( silk_nsq_state ) ); psEnc->sCmn.indices.Seed = seed_copy; psEnc->sCmn.ec_prevLagIndex = ec_prevLagIndex_copy; psEnc->sCmn.ec_prevSignalType = ec_prevSignalType_copy; } /*****************************************/ /* Noise shaping quantization */ /*****************************************/ silk_NSQ_wrapper_FLP( psEnc, &sEncCtrl, &psEnc->sCmn.indices, &psEnc->sCmn.sNSQ, psEnc->sCmn.pulses, xfw ); /****************************************/ /* Encode Parameters */ /****************************************/ silk_encode_indices( &psEnc->sCmn, psRangeEnc, psEnc->sCmn.nFramesEncoded, 0, condCoding ); /****************************************/ /* Encode Excitation Signal */ /****************************************/ silk_encode_pulses( psRangeEnc, psEnc->sCmn.indices.signalType, psEnc->sCmn.indices.quantOffsetType, psEnc->sCmn.pulses, psEnc->sCmn.frame_length ); nBits = ec_tell( psRangeEnc ); if( useCBR == 0 && iter == 0 && nBits <= maxBits ) { break; } } if( iter == maxIter ) { if( found_lower && ( gainsID == gainsID_lower || nBits > maxBits ) ) { /* Restore output state from earlier iteration that did meet the bitrate budget */ silk_memcpy( psRangeEnc, &sRangeEnc_copy2, sizeof( ec_enc ) ); silk_assert( sRangeEnc_copy2.offs <= 1275 ); silk_memcpy( psRangeEnc->buf, ec_buf_copy, sRangeEnc_copy2.offs ); silk_memcpy( &psEnc->sCmn.sNSQ, &sNSQ_copy2, sizeof( silk_nsq_state ) ); psEnc->sShape.LastGainIndex = LastGainIndex_copy2; } break; } if( nBits > maxBits ) { if( found_lower == 0 && iter >= 2 ) { /* Adjust the quantizer's rate/distortion tradeoff and discard previous "upper" results */ sEncCtrl.Lambda *= 1.5f; found_upper = 0; gainsID_upper = -1; } else { found_upper = 1; nBits_upper = nBits; gainMult_upper = gainMult_Q8; gainsID_upper = gainsID; } } else if( nBits < maxBits - 5 ) { found_lower = 1; nBits_lower = nBits; gainMult_lower = gainMult_Q8; if( gainsID != gainsID_lower ) { gainsID_lower = gainsID; /* Copy part of the output state */ silk_memcpy( &sRangeEnc_copy2, psRangeEnc, sizeof( ec_enc ) ); silk_assert( psRangeEnc->offs <= 1275 ); silk_memcpy( ec_buf_copy, psRangeEnc->buf, psRangeEnc->offs ); silk_memcpy( &sNSQ_copy2, &psEnc->sCmn.sNSQ, sizeof( silk_nsq_state ) ); LastGainIndex_copy2 = psEnc->sShape.LastGainIndex; } } else { /* Within 5 bits of budget: close enough */ break; } if( ( found_lower & found_upper ) == 0 ) { /* Adjust gain according to high-rate rate/distortion curve */ opus_int32 gain_factor_Q16; gain_factor_Q16 = silk_log2lin( silk_LSHIFT( nBits - maxBits, 7 ) / psEnc->sCmn.frame_length + SILK_FIX_CONST( 16, 7 ) ); gain_factor_Q16 = silk_min_32( gain_factor_Q16, SILK_FIX_CONST( 2, 16 ) ); if( nBits > maxBits ) { gain_factor_Q16 = silk_max_32( gain_factor_Q16, SILK_FIX_CONST( 1.3, 16 ) ); } gainMult_Q8 = silk_SMULWB( gain_factor_Q16, gainMult_Q8 ); } else { /* Adjust gain by interpolating */ gainMult_Q8 = gainMult_lower + ( ( gainMult_upper - gainMult_lower ) * ( maxBits - nBits_lower ) ) / ( nBits_upper - nBits_lower ); /* New gain multplier must be between 25% and 75% of old range (note that gainMult_upper < gainMult_lower) */ if( gainMult_Q8 > silk_ADD_RSHIFT32( gainMult_lower, gainMult_upper - gainMult_lower, 2 ) ) { gainMult_Q8 = silk_ADD_RSHIFT32( gainMult_lower, gainMult_upper - gainMult_lower, 2 ); } else if( gainMult_Q8 < silk_SUB_RSHIFT32( gainMult_upper, gainMult_upper - gainMult_lower, 2 ) ) { gainMult_Q8 = silk_SUB_RSHIFT32( gainMult_upper, gainMult_upper - gainMult_lower, 2 ); } } for( i = 0; i < psEnc->sCmn.nb_subfr; i++ ) { pGains_Q16[ i ] = silk_LSHIFT_SAT32( silk_SMULWB( sEncCtrl.GainsUnq_Q16[ i ], gainMult_Q8 ), 8 ); } /* Quantize gains */ psEnc->sShape.LastGainIndex = sEncCtrl.lastGainIndexPrev; silk_gains_quant( psEnc->sCmn.indices.GainsIndices, pGains_Q16, &psEnc->sShape.LastGainIndex, condCoding == CODE_CONDITIONALLY, psEnc->sCmn.nb_subfr ); /* Unique identifier of gains vector */ gainsID = silk_gains_ID( psEnc->sCmn.indices.GainsIndices, psEnc->sCmn.nb_subfr ); /* Overwrite unquantized gains with quantized gains and convert back to Q0 from Q16 */ for( i = 0; i < psEnc->sCmn.nb_subfr; i++ ) { sEncCtrl.Gains[ i ] = pGains_Q16[ i ] / 65536.0f; } } } /* Update input buffer */ silk_memmove( psEnc->x_buf, &psEnc->x_buf[ psEnc->sCmn.frame_length ], ( psEnc->sCmn.ltp_mem_length + LA_SHAPE_MS * psEnc->sCmn.fs_kHz ) * sizeof( silk_float ) ); /* Parameters needed for next frame */ psEnc->sCmn.prevLag = sEncCtrl.pitchL[ psEnc->sCmn.nb_subfr - 1 ]; psEnc->sCmn.prevSignalType = psEnc->sCmn.indices.signalType; /* Exit without entropy coding */ if( psEnc->sCmn.prefillFlag ) { /* No payload */ *pnBytesOut = 0; return ret; } /****************************************/ /* Finalize payload */ /****************************************/ psEnc->sCmn.first_frame_after_reset = 0; /* Payload size */ *pnBytesOut = silk_RSHIFT( ec_tell( psRangeEnc ) + 7, 3 ); return ret; }
void silk_find_LTP_FIX( opus_int16 b_Q14[ MAX_NB_SUBFR * LTP_ORDER ], /* O LTP coefs */ opus_int32 WLTP[ MAX_NB_SUBFR * LTP_ORDER * LTP_ORDER ], /* O Weight for LTP quantization */ opus_int *LTPredCodGain_Q7, /* O LTP coding gain */ const opus_int16 r_lpc[], /* I residual signal after LPC signal + state for first 10 ms */ const opus_int lag[ MAX_NB_SUBFR ], /* I LTP lags */ const opus_int32 Wght_Q15[ MAX_NB_SUBFR ], /* I weights */ const opus_int subfr_length, /* I subframe length */ const opus_int nb_subfr, /* I number of subframes */ const opus_int mem_offset, /* I number of samples in LTP memory */ opus_int corr_rshifts[ MAX_NB_SUBFR ] /* O right shifts applied to correlations */ ) { opus_int i, k, lshift; const opus_int16 *r_ptr, *lag_ptr; opus_int16 *b_Q14_ptr; opus_int32 regu; opus_int32 *WLTP_ptr; opus_int32 b_Q16[ LTP_ORDER ], delta_b_Q14[ LTP_ORDER ], d_Q14[ MAX_NB_SUBFR ], nrg[ MAX_NB_SUBFR ], g_Q26; opus_int32 w[ MAX_NB_SUBFR ], WLTP_max, max_abs_d_Q14, max_w_bits; opus_int32 temp32, denom32; opus_int extra_shifts; opus_int rr_shifts, maxRshifts, maxRshifts_wxtra, LZs; opus_int32 LPC_res_nrg, LPC_LTP_res_nrg, div_Q16; opus_int32 Rr[ LTP_ORDER ], rr[ MAX_NB_SUBFR ]; opus_int32 wd, m_Q12; b_Q14_ptr = b_Q14; WLTP_ptr = WLTP; r_ptr = &r_lpc[ mem_offset ]; for( k = 0; k < nb_subfr; k++ ) { lag_ptr = r_ptr - ( lag[ k ] + LTP_ORDER / 2 ); silk_sum_sqr_shift( &rr[ k ], &rr_shifts, r_ptr, subfr_length ); /* rr[ k ] in Q( -rr_shifts ) */ /* Assure headroom */ LZs = silk_CLZ32( rr[k] ); if( LZs < LTP_CORRS_HEAD_ROOM ) { rr[ k ] = silk_RSHIFT_ROUND( rr[ k ], LTP_CORRS_HEAD_ROOM - LZs ); rr_shifts += ( LTP_CORRS_HEAD_ROOM - LZs ); } corr_rshifts[ k ] = rr_shifts; silk_corrMatrix_FIX( lag_ptr, subfr_length, LTP_ORDER, LTP_CORRS_HEAD_ROOM, WLTP_ptr, &corr_rshifts[ k ] ); /* WLTP_fix_ptr in Q( -corr_rshifts[ k ] ) */ /* The correlation vector always has lower max abs value than rr and/or RR so head room is assured */ silk_corrVector_FIX( lag_ptr, r_ptr, subfr_length, LTP_ORDER, Rr, corr_rshifts[ k ] ); /* Rr_fix_ptr in Q( -corr_rshifts[ k ] ) */ if( corr_rshifts[ k ] > rr_shifts ) { rr[ k ] = silk_RSHIFT( rr[ k ], corr_rshifts[ k ] - rr_shifts ); /* rr[ k ] in Q( -corr_rshifts[ k ] ) */ } silk_assert( rr[ k ] >= 0 ); regu = 1; regu = silk_SMLAWB( regu, rr[ k ], SILK_FIX_CONST( LTP_DAMPING/3, 16 ) ); regu = silk_SMLAWB( regu, matrix_ptr( WLTP_ptr, 0, 0, LTP_ORDER ), SILK_FIX_CONST( LTP_DAMPING/3, 16 ) ); regu = silk_SMLAWB( regu, matrix_ptr( WLTP_ptr, LTP_ORDER-1, LTP_ORDER-1, LTP_ORDER ), SILK_FIX_CONST( LTP_DAMPING/3, 16 ) ); silk_regularize_correlations_FIX( WLTP_ptr, &rr[k], regu, LTP_ORDER ); silk_solve_LDL_FIX( WLTP_ptr, LTP_ORDER, Rr, b_Q16 ); /* WLTP_fix_ptr and Rr_fix_ptr both in Q(-corr_rshifts[k]) */ /* Limit and store in Q14 */ silk_fit_LTP( b_Q16, b_Q14_ptr ); /* Calculate residual energy */ nrg[ k ] = silk_residual_energy16_covar_FIX( b_Q14_ptr, WLTP_ptr, Rr, rr[ k ], LTP_ORDER, 14 ); /* nrg_fix in Q( -corr_rshifts[ k ] ) */ /* temp = Wght[ k ] / ( nrg[ k ] * Wght[ k ] + 0.01f * subfr_length ); */ extra_shifts = silk_min_int( corr_rshifts[ k ], LTP_CORRS_HEAD_ROOM ); denom32 = silk_LSHIFT_SAT32( silk_SMULWB( nrg[ k ], Wght_Q15[ k ] ), 1 + extra_shifts ) + /* Q( -corr_rshifts[ k ] + extra_shifts ) */ silk_RSHIFT( silk_SMULWB( (opus_int32)subfr_length, 655 ), corr_rshifts[ k ] - extra_shifts ); /* Q( -corr_rshifts[ k ] + extra_shifts ) */ denom32 = silk_max( denom32, 1 ); silk_assert( ((opus_int64)Wght_Q15[ k ] << 16 ) < silk_int32_MAX ); /* Wght always < 0.5 in Q0 */ temp32 = silk_DIV32( silk_LSHIFT( (opus_int32)Wght_Q15[ k ], 16 ), denom32 ); /* Q( 15 + 16 + corr_rshifts[k] - extra_shifts ) */ temp32 = silk_RSHIFT( temp32, 31 + corr_rshifts[ k ] - extra_shifts - 26 ); /* Q26 */ /* Limit temp such that the below scaling never wraps around */ WLTP_max = 0; for( i = 0; i < LTP_ORDER * LTP_ORDER; i++ ) { WLTP_max = silk_max( WLTP_ptr[ i ], WLTP_max ); } lshift = silk_CLZ32( WLTP_max ) - 1 - 3; /* keep 3 bits free for vq_nearest_neighbor_fix */ silk_assert( 26 - 18 + lshift >= 0 ); if( 26 - 18 + lshift < 31 ) { temp32 = silk_min_32( temp32, silk_LSHIFT( (opus_int32)1, 26 - 18 + lshift ) ); } silk_scale_vector32_Q26_lshift_18( WLTP_ptr, temp32, LTP_ORDER * LTP_ORDER ); /* WLTP_ptr in Q( 18 - corr_rshifts[ k ] ) */ w[ k ] = matrix_ptr( WLTP_ptr, LTP_ORDER/2, LTP_ORDER/2, LTP_ORDER ); /* w in Q( 18 - corr_rshifts[ k ] ) */ silk_assert( w[k] >= 0 ); r_ptr += subfr_length; b_Q14_ptr += LTP_ORDER; WLTP_ptr += LTP_ORDER * LTP_ORDER; } maxRshifts = 0; for( k = 0; k < nb_subfr; k++ ) { maxRshifts = silk_max_int( corr_rshifts[ k ], maxRshifts ); } /* Compute LTP coding gain */ if( LTPredCodGain_Q7 != NULL ) { LPC_LTP_res_nrg = 0; LPC_res_nrg = 0; silk_assert( LTP_CORRS_HEAD_ROOM >= 2 ); /* Check that no overflow will happen when adding */ for( k = 0; k < nb_subfr; k++ ) { LPC_res_nrg = silk_ADD32( LPC_res_nrg, silk_RSHIFT( silk_ADD32( silk_SMULWB( rr[ k ], Wght_Q15[ k ] ), 1 ), 1 + ( maxRshifts - corr_rshifts[ k ] ) ) ); /* Q( -maxRshifts ) */ LPC_LTP_res_nrg = silk_ADD32( LPC_LTP_res_nrg, silk_RSHIFT( silk_ADD32( silk_SMULWB( nrg[ k ], Wght_Q15[ k ] ), 1 ), 1 + ( maxRshifts - corr_rshifts[ k ] ) ) ); /* Q( -maxRshifts ) */ } LPC_LTP_res_nrg = silk_max( LPC_LTP_res_nrg, 1 ); /* avoid division by zero */ div_Q16 = silk_DIV32_varQ( LPC_res_nrg, LPC_LTP_res_nrg, 16 ); *LTPredCodGain_Q7 = ( opus_int )silk_SMULBB( 3, silk_lin2log( div_Q16 ) - ( 16 << 7 ) ); silk_assert( *LTPredCodGain_Q7 == ( opus_int )silk_SAT16( silk_MUL( 3, silk_lin2log( div_Q16 ) - ( 16 << 7 ) ) ) ); } /* smoothing */ /* d = sum( B, 1 ); */ b_Q14_ptr = b_Q14; for( k = 0; k < nb_subfr; k++ ) { d_Q14[ k ] = 0; for( i = 0; i < LTP_ORDER; i++ ) { d_Q14[ k ] += b_Q14_ptr[ i ]; } b_Q14_ptr += LTP_ORDER; } /* m = ( w * d' ) / ( sum( w ) + 1e-3 ); */ /* Find maximum absolute value of d_Q14 and the bits used by w in Q0 */ max_abs_d_Q14 = 0; max_w_bits = 0; for( k = 0; k < nb_subfr; k++ ) { max_abs_d_Q14 = silk_max_32( max_abs_d_Q14, silk_abs( d_Q14[ k ] ) ); /* w[ k ] is in Q( 18 - corr_rshifts[ k ] ) */ /* Find bits needed in Q( 18 - maxRshifts ) */ max_w_bits = silk_max_32( max_w_bits, 32 - silk_CLZ32( w[ k ] ) + corr_rshifts[ k ] - maxRshifts ); } /* max_abs_d_Q14 = (5 << 15); worst case, i.e. LTP_ORDER * -silk_int16_MIN */ silk_assert( max_abs_d_Q14 <= ( 5 << 15 ) ); /* How many bits is needed for w*d' in Q( 18 - maxRshifts ) in the worst case, of all d_Q14's being equal to max_abs_d_Q14 */ extra_shifts = max_w_bits + 32 - silk_CLZ32( max_abs_d_Q14 ) - 14; /* Subtract what we got available; bits in output var plus maxRshifts */ extra_shifts -= ( 32 - 1 - 2 + maxRshifts ); /* Keep sign bit free as well as 2 bits for accumulation */ extra_shifts = silk_max_int( extra_shifts, 0 ); maxRshifts_wxtra = maxRshifts + extra_shifts; temp32 = silk_RSHIFT( 262, maxRshifts + extra_shifts ) + 1; /* 1e-3f in Q( 18 - (maxRshifts + extra_shifts) ) */ wd = 0; for( k = 0; k < nb_subfr; k++ ) { /* w has at least 2 bits of headroom so no overflow should happen */ temp32 = silk_ADD32( temp32, silk_RSHIFT( w[ k ], maxRshifts_wxtra - corr_rshifts[ k ] ) ); /* Q( 18 - maxRshifts_wxtra ) */ wd = silk_ADD32( wd, silk_LSHIFT( silk_SMULWW( silk_RSHIFT( w[ k ], maxRshifts_wxtra - corr_rshifts[ k ] ), d_Q14[ k ] ), 2 ) ); /* Q( 18 - maxRshifts_wxtra ) */ } m_Q12 = silk_DIV32_varQ( wd, temp32, 12 ); b_Q14_ptr = b_Q14; for( k = 0; k < nb_subfr; k++ ) { /* w_fix[ k ] from Q( 18 - corr_rshifts[ k ] ) to Q( 16 ) */ if( 2 - corr_rshifts[k] > 0 ) { temp32 = silk_RSHIFT( w[ k ], 2 - corr_rshifts[ k ] ); } else { temp32 = silk_LSHIFT_SAT32( w[ k ], corr_rshifts[ k ] - 2 ); } g_Q26 = silk_MUL( silk_DIV32( SILK_FIX_CONST( LTP_SMOOTHING, 26 ), silk_RSHIFT( SILK_FIX_CONST( LTP_SMOOTHING, 26 ), 10 ) + temp32 ), /* Q10 */ silk_LSHIFT_SAT32( silk_SUB_SAT32( (opus_int32)m_Q12, silk_RSHIFT( d_Q14[ k ], 2 ) ), 4 ) ); /* Q16 */ temp32 = 0; for( i = 0; i < LTP_ORDER; i++ ) { delta_b_Q14[ i ] = silk_max_16( b_Q14_ptr[ i ], 1638 ); /* 1638_Q14 = 0.1_Q0 */ temp32 += delta_b_Q14[ i ]; /* Q14 */ } temp32 = silk_DIV32( g_Q26, temp32 ); /* Q14 -> Q12 */ for( i = 0; i < LTP_ORDER; i++ ) { b_Q14_ptr[ i ] = silk_LIMIT_32( (opus_int32)b_Q14_ptr[ i ] + silk_SMULWB( silk_LSHIFT_SAT32( temp32, 4 ), delta_b_Q14[ i ] ), -16000, 28000 ); } b_Q14_ptr += LTP_ORDER; } }