| /*********************************************************************** |
| Copyright (c) 2006-2011, Skype Limited. All rights reserved. |
| Redistribution and use in source and binary forms, with or without |
| modification, are permitted provided that the following conditions |
| are met: |
| - Redistributions of source code must retain the above copyright notice, |
| this list of conditions and the following disclaimer. |
| - Redistributions in binary form must reproduce the above copyright |
| notice, this list of conditions and the following disclaimer in the |
| documentation and/or other materials provided with the distribution. |
| - Neither the name of Internet Society, IETF or IETF Trust, nor the |
| names of specific contributors, may be used to endorse or promote |
| products derived from this software without specific prior written |
| permission. |
| THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" |
| AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE |
| LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR |
| CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF |
| SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
| INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN |
| CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
| ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE |
| POSSIBILITY OF SUCH DAMAGE. |
| ***********************************************************************/ |
| |
| #ifdef HAVE_CONFIG_H |
| #include "config.h" |
| #endif |
| |
| #include "main.h" |
| #include "stack_alloc.h" |
| #include "PLC.h" |
| |
| #define NB_ATT 2 |
| static const opus_int16 HARM_ATT_Q15[NB_ATT] = { 32440, 31130 }; /* 0.99, 0.95 */ |
| static const opus_int16 PLC_RAND_ATTENUATE_V_Q15[NB_ATT] = { 31130, 26214 }; /* 0.95, 0.8 */ |
| static const opus_int16 PLC_RAND_ATTENUATE_UV_Q15[NB_ATT] = { 32440, 29491 }; /* 0.99, 0.9 */ |
| |
| static inline void silk_PLC_update( |
| silk_decoder_state *psDec, /* I/O Decoder state */ |
| silk_decoder_control *psDecCtrl /* I/O Decoder control */ |
| ); |
| |
| static inline void silk_PLC_conceal( |
| silk_decoder_state *psDec, /* I/O Decoder state */ |
| silk_decoder_control *psDecCtrl, /* I/O Decoder control */ |
| opus_int16 frame[] /* O LPC residual signal */ |
| ); |
| |
| |
| void silk_PLC_Reset( |
| silk_decoder_state *psDec /* I/O Decoder state */ |
| ) |
| { |
| psDec->sPLC.pitchL_Q8 = silk_LSHIFT( psDec->frame_length, 8 - 1 ); |
| psDec->sPLC.prevGain_Q16[ 0 ] = SILK_FIX_CONST( 1, 16 ); |
| psDec->sPLC.prevGain_Q16[ 1 ] = SILK_FIX_CONST( 1, 16 ); |
| psDec->sPLC.subfr_length = 20; |
| psDec->sPLC.nb_subfr = 2; |
| } |
| |
| void silk_PLC( |
| silk_decoder_state *psDec, /* I/O Decoder state */ |
| silk_decoder_control *psDecCtrl, /* I/O Decoder control */ |
| opus_int16 frame[], /* I/O signal */ |
| opus_int lost /* I Loss flag */ |
| ) |
| { |
| /* PLC control function */ |
| if( psDec->fs_kHz != psDec->sPLC.fs_kHz ) { |
| silk_PLC_Reset( psDec ); |
| psDec->sPLC.fs_kHz = psDec->fs_kHz; |
| } |
| |
| if( lost ) { |
| /****************************/ |
| /* Generate Signal */ |
| /****************************/ |
| silk_PLC_conceal( psDec, psDecCtrl, frame ); |
| |
| psDec->lossCnt++; |
| } else { |
| /****************************/ |
| /* Update state */ |
| /****************************/ |
| silk_PLC_update( psDec, psDecCtrl ); |
| } |
| } |
| |
| /**************************************************/ |
| /* Update state of PLC */ |
| /**************************************************/ |
| static inline void silk_PLC_update( |
| silk_decoder_state *psDec, /* I/O Decoder state */ |
| silk_decoder_control *psDecCtrl /* I/O Decoder control */ |
| ) |
| { |
| opus_int32 LTP_Gain_Q14, temp_LTP_Gain_Q14; |
| opus_int i, j; |
| silk_PLC_struct *psPLC; |
| |
| psPLC = &psDec->sPLC; |
| |
| /* Update parameters used in case of packet loss */ |
| psDec->prevSignalType = psDec->indices.signalType; |
| LTP_Gain_Q14 = 0; |
| if( psDec->indices.signalType == TYPE_VOICED ) { |
| /* Find the parameters for the last subframe which contains a pitch pulse */ |
| for( j = 0; j * psDec->subfr_length < psDecCtrl->pitchL[ psDec->nb_subfr - 1 ]; j++ ) { |
| if( j == psDec->nb_subfr ) { |
| break; |
| } |
| temp_LTP_Gain_Q14 = 0; |
| for( i = 0; i < LTP_ORDER; i++ ) { |
| temp_LTP_Gain_Q14 += psDecCtrl->LTPCoef_Q14[ ( psDec->nb_subfr - 1 - j ) * LTP_ORDER + i ]; |
| } |
| if( temp_LTP_Gain_Q14 > LTP_Gain_Q14 ) { |
| LTP_Gain_Q14 = temp_LTP_Gain_Q14; |
| silk_memcpy( psPLC->LTPCoef_Q14, |
| &psDecCtrl->LTPCoef_Q14[ silk_SMULBB( psDec->nb_subfr - 1 - j, LTP_ORDER ) ], |
| LTP_ORDER * sizeof( opus_int16 ) ); |
| |
| psPLC->pitchL_Q8 = silk_LSHIFT( psDecCtrl->pitchL[ psDec->nb_subfr - 1 - j ], 8 ); |
| } |
| } |
| |
| silk_memset( psPLC->LTPCoef_Q14, 0, LTP_ORDER * sizeof( opus_int16 ) ); |
| psPLC->LTPCoef_Q14[ LTP_ORDER / 2 ] = LTP_Gain_Q14; |
| |
| /* Limit LT coefs */ |
| if( LTP_Gain_Q14 < V_PITCH_GAIN_START_MIN_Q14 ) { |
| opus_int scale_Q10; |
| opus_int32 tmp; |
| |
| tmp = silk_LSHIFT( V_PITCH_GAIN_START_MIN_Q14, 10 ); |
| scale_Q10 = silk_DIV32( tmp, silk_max( LTP_Gain_Q14, 1 ) ); |
| for( i = 0; i < LTP_ORDER; i++ ) { |
| psPLC->LTPCoef_Q14[ i ] = silk_RSHIFT( silk_SMULBB( psPLC->LTPCoef_Q14[ i ], scale_Q10 ), 10 ); |
| } |
| } else if( LTP_Gain_Q14 > V_PITCH_GAIN_START_MAX_Q14 ) { |
| opus_int scale_Q14; |
| opus_int32 tmp; |
| |
| tmp = silk_LSHIFT( V_PITCH_GAIN_START_MAX_Q14, 14 ); |
| scale_Q14 = silk_DIV32( tmp, silk_max( LTP_Gain_Q14, 1 ) ); |
| for( i = 0; i < LTP_ORDER; i++ ) { |
| psPLC->LTPCoef_Q14[ i ] = silk_RSHIFT( silk_SMULBB( psPLC->LTPCoef_Q14[ i ], scale_Q14 ), 14 ); |
| } |
| } |
| } else { |
| psPLC->pitchL_Q8 = silk_LSHIFT( silk_SMULBB( psDec->fs_kHz, 18 ), 8 ); |
| silk_memset( psPLC->LTPCoef_Q14, 0, LTP_ORDER * sizeof( opus_int16 )); |
| } |
| |
| /* Save LPC coeficients */ |
| silk_memcpy( psPLC->prevLPC_Q12, psDecCtrl->PredCoef_Q12[ 1 ], psDec->LPC_order * sizeof( opus_int16 ) ); |
| psPLC->prevLTP_scale_Q14 = psDecCtrl->LTP_scale_Q14; |
| |
| /* Save last two gains */ |
| silk_memcpy( psPLC->prevGain_Q16, &psDecCtrl->Gains_Q16[ psDec->nb_subfr - 2 ], 2 * sizeof( opus_int32 ) ); |
| |
| psPLC->subfr_length = psDec->subfr_length; |
| psPLC->nb_subfr = psDec->nb_subfr; |
| } |
| |
| static inline void silk_PLC_conceal( |
| silk_decoder_state *psDec, /* I/O Decoder state */ |
| silk_decoder_control *psDecCtrl, /* I/O Decoder control */ |
| opus_int16 frame[] /* O LPC residual signal */ |
| ) |
| { |
| opus_int i, j, k; |
| opus_int lag, idx, sLTP_buf_idx, shift1, shift2; |
| opus_int32 rand_seed, harm_Gain_Q15, rand_Gain_Q15, inv_gain_Q30; |
| opus_int32 energy1, energy2, *rand_ptr, *pred_lag_ptr; |
| opus_int32 LPC_pred_Q10, LTP_pred_Q12; |
| opus_int16 rand_scale_Q14; |
| opus_int16 *B_Q14, *exc_buf_ptr; |
| opus_int32 *sLPC_Q14_ptr; |
| VARDECL( opus_int16, exc_buf ); |
| opus_int16 A_Q12[ MAX_LPC_ORDER ]; |
| VARDECL( opus_int16, sLTP ); |
| VARDECL( opus_int32, sLTP_Q14 ); |
| silk_PLC_struct *psPLC = &psDec->sPLC; |
| opus_int32 prevGain_Q10[2]; |
| SAVE_STACK; |
| |
| ALLOC( exc_buf, 2*psPLC->subfr_length, opus_int16 ); |
| ALLOC( sLTP, psDec->ltp_mem_length, opus_int16 ); |
| ALLOC( sLTP_Q14, psDec->ltp_mem_length + psDec->frame_length, opus_int32 ); |
| |
| prevGain_Q10[0] = silk_RSHIFT( psPLC->prevGain_Q16[ 0 ], 6); |
| prevGain_Q10[1] = silk_RSHIFT( psPLC->prevGain_Q16[ 1 ], 6); |
| |
| if( psDec->first_frame_after_reset ) { |
| silk_memset( psPLC->prevLPC_Q12, 0, sizeof( psPLC->prevLPC_Q12 ) ); |
| } |
| |
| /* Find random noise component */ |
| /* Scale previous excitation signal */ |
| exc_buf_ptr = exc_buf; |
| for( k = 0; k < 2; k++ ) { |
| for( i = 0; i < psPLC->subfr_length; i++ ) { |
| exc_buf_ptr[ i ] = (opus_int16)silk_SAT16( silk_RSHIFT( |
| silk_SMULWW( psDec->exc_Q14[ i + ( k + psPLC->nb_subfr - 2 ) * psPLC->subfr_length ], prevGain_Q10[ k ] ), 8 ) ); |
| } |
| exc_buf_ptr += psPLC->subfr_length; |
| } |
| /* Find the subframe with lowest energy of the last two and use that as random noise generator */ |
| silk_sum_sqr_shift( &energy1, &shift1, exc_buf, psPLC->subfr_length ); |
| silk_sum_sqr_shift( &energy2, &shift2, &exc_buf[ psPLC->subfr_length ], psPLC->subfr_length ); |
| |
| if( silk_RSHIFT( energy1, shift2 ) < silk_RSHIFT( energy2, shift1 ) ) { |
| /* First sub-frame has lowest energy */ |
| rand_ptr = &psDec->exc_Q14[ silk_max_int( 0, ( psPLC->nb_subfr - 1 ) * psPLC->subfr_length - RAND_BUF_SIZE ) ]; |
| } else { |
| /* Second sub-frame has lowest energy */ |
| rand_ptr = &psDec->exc_Q14[ silk_max_int( 0, psPLC->nb_subfr * psPLC->subfr_length - RAND_BUF_SIZE ) ]; |
| } |
| |
| /* Set up Gain to random noise component */ |
| B_Q14 = psPLC->LTPCoef_Q14; |
| rand_scale_Q14 = psPLC->randScale_Q14; |
| |
| /* Set up attenuation gains */ |
| harm_Gain_Q15 = HARM_ATT_Q15[ silk_min_int( NB_ATT - 1, psDec->lossCnt ) ]; |
| if( psDec->prevSignalType == TYPE_VOICED ) { |
| rand_Gain_Q15 = PLC_RAND_ATTENUATE_V_Q15[ silk_min_int( NB_ATT - 1, psDec->lossCnt ) ]; |
| } else { |
| rand_Gain_Q15 = PLC_RAND_ATTENUATE_UV_Q15[ silk_min_int( NB_ATT - 1, psDec->lossCnt ) ]; |
| } |
| |
| /* LPC concealment. Apply BWE to previous LPC */ |
| silk_bwexpander( psPLC->prevLPC_Q12, psDec->LPC_order, SILK_FIX_CONST( BWE_COEF, 16 ) ); |
| |
| /* Preload LPC coeficients to array on stack. Gives small performance gain */ |
| silk_memcpy( A_Q12, psPLC->prevLPC_Q12, psDec->LPC_order * sizeof( opus_int16 ) ); |
| |
| /* First Lost frame */ |
| if( psDec->lossCnt == 0 ) { |
| rand_scale_Q14 = 1 << 14; |
| |
| /* Reduce random noise Gain for voiced frames */ |
| if( psDec->prevSignalType == TYPE_VOICED ) { |
| for( i = 0; i < LTP_ORDER; i++ ) { |
| rand_scale_Q14 -= B_Q14[ i ]; |
| } |
| rand_scale_Q14 = silk_max_16( 3277, rand_scale_Q14 ); /* 0.2 */ |
| rand_scale_Q14 = (opus_int16)silk_RSHIFT( silk_SMULBB( rand_scale_Q14, psPLC->prevLTP_scale_Q14 ), 14 ); |
| } else { |
| /* Reduce random noise for unvoiced frames with high LPC gain */ |
| opus_int32 invGain_Q30, down_scale_Q30; |
| |
| invGain_Q30 = silk_LPC_inverse_pred_gain( psPLC->prevLPC_Q12, psDec->LPC_order ); |
| |
| down_scale_Q30 = silk_min_32( silk_RSHIFT( (opus_int32)1 << 30, LOG2_INV_LPC_GAIN_HIGH_THRES ), invGain_Q30 ); |
| down_scale_Q30 = silk_max_32( silk_RSHIFT( (opus_int32)1 << 30, LOG2_INV_LPC_GAIN_LOW_THRES ), down_scale_Q30 ); |
| down_scale_Q30 = silk_LSHIFT( down_scale_Q30, LOG2_INV_LPC_GAIN_HIGH_THRES ); |
| |
| rand_Gain_Q15 = silk_RSHIFT( silk_SMULWB( down_scale_Q30, rand_Gain_Q15 ), 14 ); |
| } |
| } |
| |
| rand_seed = psPLC->rand_seed; |
| lag = silk_RSHIFT_ROUND( psPLC->pitchL_Q8, 8 ); |
| sLTP_buf_idx = psDec->ltp_mem_length; |
| |
| /* Rewhiten LTP state */ |
| idx = psDec->ltp_mem_length - lag - psDec->LPC_order - LTP_ORDER / 2; |
| silk_assert( idx > 0 ); |
| silk_LPC_analysis_filter( &sLTP[ idx ], &psDec->outBuf[ idx ], A_Q12, psDec->ltp_mem_length - idx, psDec->LPC_order ); |
| /* Scale LTP state */ |
| inv_gain_Q30 = silk_INVERSE32_varQ( psPLC->prevGain_Q16[ 1 ], 46 ); |
| inv_gain_Q30 = silk_min( inv_gain_Q30, silk_int32_MAX >> 1 ); |
| for( i = idx + psDec->LPC_order; i < psDec->ltp_mem_length; i++ ) { |
| sLTP_Q14[ i ] = silk_SMULWB( inv_gain_Q30, sLTP[ i ] ); |
| } |
| |
| /***************************/ |
| /* LTP synthesis filtering */ |
| /***************************/ |
| for( k = 0; k < psDec->nb_subfr; k++ ) { |
| /* Set up pointer */ |
| pred_lag_ptr = &sLTP_Q14[ sLTP_buf_idx - lag + LTP_ORDER / 2 ]; |
| for( i = 0; i < psDec->subfr_length; i++ ) { |
| /* Unrolled loop */ |
| /* Avoids introducing a bias because silk_SMLAWB() always rounds to -inf */ |
| LTP_pred_Q12 = 2; |
| LTP_pred_Q12 = silk_SMLAWB( LTP_pred_Q12, pred_lag_ptr[ 0 ], B_Q14[ 0 ] ); |
| LTP_pred_Q12 = silk_SMLAWB( LTP_pred_Q12, pred_lag_ptr[ -1 ], B_Q14[ 1 ] ); |
| LTP_pred_Q12 = silk_SMLAWB( LTP_pred_Q12, pred_lag_ptr[ -2 ], B_Q14[ 2 ] ); |
| LTP_pred_Q12 = silk_SMLAWB( LTP_pred_Q12, pred_lag_ptr[ -3 ], B_Q14[ 3 ] ); |
| LTP_pred_Q12 = silk_SMLAWB( LTP_pred_Q12, pred_lag_ptr[ -4 ], B_Q14[ 4 ] ); |
| pred_lag_ptr++; |
| |
| /* Generate LPC excitation */ |
| rand_seed = silk_RAND( rand_seed ); |
| idx = silk_RSHIFT( rand_seed, 25 ) & RAND_BUF_MASK; |
| sLTP_Q14[ sLTP_buf_idx ] = silk_LSHIFT32( silk_SMLAWB( LTP_pred_Q12, rand_ptr[ idx ], rand_scale_Q14 ), 2 ); |
| sLTP_buf_idx++; |
| } |
| |
| /* Gradually reduce LTP gain */ |
| for( j = 0; j < LTP_ORDER; j++ ) { |
| B_Q14[ j ] = silk_RSHIFT( silk_SMULBB( harm_Gain_Q15, B_Q14[ j ] ), 15 ); |
| } |
| /* Gradually reduce excitation gain */ |
| rand_scale_Q14 = silk_RSHIFT( silk_SMULBB( rand_scale_Q14, rand_Gain_Q15 ), 15 ); |
| |
| /* Slowly increase pitch lag */ |
| psPLC->pitchL_Q8 = silk_SMLAWB( psPLC->pitchL_Q8, psPLC->pitchL_Q8, PITCH_DRIFT_FAC_Q16 ); |
| psPLC->pitchL_Q8 = silk_min_32( psPLC->pitchL_Q8, silk_LSHIFT( silk_SMULBB( MAX_PITCH_LAG_MS, psDec->fs_kHz ), 8 ) ); |
| lag = silk_RSHIFT_ROUND( psPLC->pitchL_Q8, 8 ); |
| } |
| |
| /***************************/ |
| /* LPC synthesis filtering */ |
| /***************************/ |
| sLPC_Q14_ptr = &sLTP_Q14[ psDec->ltp_mem_length - MAX_LPC_ORDER ]; |
| |
| /* Copy LPC state */ |
| silk_memcpy( sLPC_Q14_ptr, psDec->sLPC_Q14_buf, MAX_LPC_ORDER * sizeof( opus_int32 ) ); |
| |
| silk_assert( psDec->LPC_order >= 10 ); /* check that unrolling works */ |
| for( i = 0; i < psDec->frame_length; i++ ) { |
| /* partly unrolled */ |
| /* Avoids introducing a bias because silk_SMLAWB() always rounds to -inf */ |
| LPC_pred_Q10 = silk_RSHIFT( psDec->LPC_order, 1 ); |
| LPC_pred_Q10 = silk_SMLAWB( LPC_pred_Q10, sLPC_Q14_ptr[ MAX_LPC_ORDER + i - 1 ], A_Q12[ 0 ] ); |
| LPC_pred_Q10 = silk_SMLAWB( LPC_pred_Q10, sLPC_Q14_ptr[ MAX_LPC_ORDER + i - 2 ], A_Q12[ 1 ] ); |
| LPC_pred_Q10 = silk_SMLAWB( LPC_pred_Q10, sLPC_Q14_ptr[ MAX_LPC_ORDER + i - 3 ], A_Q12[ 2 ] ); |
| LPC_pred_Q10 = silk_SMLAWB( LPC_pred_Q10, sLPC_Q14_ptr[ MAX_LPC_ORDER + i - 4 ], A_Q12[ 3 ] ); |
| LPC_pred_Q10 = silk_SMLAWB( LPC_pred_Q10, sLPC_Q14_ptr[ MAX_LPC_ORDER + i - 5 ], A_Q12[ 4 ] ); |
| LPC_pred_Q10 = silk_SMLAWB( LPC_pred_Q10, sLPC_Q14_ptr[ MAX_LPC_ORDER + i - 6 ], A_Q12[ 5 ] ); |
| LPC_pred_Q10 = silk_SMLAWB( LPC_pred_Q10, sLPC_Q14_ptr[ MAX_LPC_ORDER + i - 7 ], A_Q12[ 6 ] ); |
| LPC_pred_Q10 = silk_SMLAWB( LPC_pred_Q10, sLPC_Q14_ptr[ MAX_LPC_ORDER + i - 8 ], A_Q12[ 7 ] ); |
| LPC_pred_Q10 = silk_SMLAWB( LPC_pred_Q10, sLPC_Q14_ptr[ MAX_LPC_ORDER + i - 9 ], A_Q12[ 8 ] ); |
| LPC_pred_Q10 = silk_SMLAWB( LPC_pred_Q10, sLPC_Q14_ptr[ MAX_LPC_ORDER + i - 10 ], A_Q12[ 9 ] ); |
| for( j = 10; j < psDec->LPC_order; j++ ) { |
| LPC_pred_Q10 = silk_SMLAWB( LPC_pred_Q10, sLPC_Q14_ptr[ MAX_LPC_ORDER + i - j - 1 ], A_Q12[ j ] ); |
| } |
| |
| /* Add prediction to LPC excitation */ |
| sLPC_Q14_ptr[ MAX_LPC_ORDER + i ] = silk_ADD_LSHIFT32( sLPC_Q14_ptr[ MAX_LPC_ORDER + i ], LPC_pred_Q10, 4 ); |
| |
| /* Scale with Gain */ |
| frame[ i ] = (opus_int16)silk_SAT16( silk_SAT16( silk_RSHIFT_ROUND( silk_SMULWW( sLPC_Q14_ptr[ MAX_LPC_ORDER + i ], prevGain_Q10[ 1 ] ), 8 ) ) ); |
| } |
| |
| /* Save LPC state */ |
| silk_memcpy( psDec->sLPC_Q14_buf, &sLPC_Q14_ptr[ psDec->frame_length ], MAX_LPC_ORDER * sizeof( opus_int32 ) ); |
| |
| /**************************************/ |
| /* Update states */ |
| /**************************************/ |
| psPLC->rand_seed = rand_seed; |
| psPLC->randScale_Q14 = rand_scale_Q14; |
| for( i = 0; i < MAX_NB_SUBFR; i++ ) { |
| psDecCtrl->pitchL[ i ] = lag; |
| } |
| RESTORE_STACK; |
| } |
| |
| /* Glues concealed frames with new good received frames */ |
| void silk_PLC_glue_frames( |
| silk_decoder_state *psDec, /* I/O decoder state */ |
| opus_int16 frame[], /* I/O signal */ |
| opus_int length /* I length of signal */ |
| ) |
| { |
| opus_int i, energy_shift; |
| opus_int32 energy; |
| silk_PLC_struct *psPLC; |
| psPLC = &psDec->sPLC; |
| |
| if( psDec->lossCnt ) { |
| /* Calculate energy in concealed residual */ |
| silk_sum_sqr_shift( &psPLC->conc_energy, &psPLC->conc_energy_shift, frame, length ); |
| |
| psPLC->last_frame_lost = 1; |
| } else { |
| if( psDec->sPLC.last_frame_lost ) { |
| /* Calculate residual in decoded signal if last frame was lost */ |
| silk_sum_sqr_shift( &energy, &energy_shift, frame, length ); |
| |
| /* Normalize energies */ |
| if( energy_shift > psPLC->conc_energy_shift ) { |
| psPLC->conc_energy = silk_RSHIFT( psPLC->conc_energy, energy_shift - psPLC->conc_energy_shift ); |
| } else if( energy_shift < psPLC->conc_energy_shift ) { |
| energy = silk_RSHIFT( energy, psPLC->conc_energy_shift - energy_shift ); |
| } |
| |
| /* Fade in the energy difference */ |
| if( energy > psPLC->conc_energy ) { |
| opus_int32 frac_Q24, LZ; |
| opus_int32 gain_Q16, slope_Q16; |
| |
| LZ = silk_CLZ32( psPLC->conc_energy ); |
| LZ = LZ - 1; |
| psPLC->conc_energy = silk_LSHIFT( psPLC->conc_energy, LZ ); |
| energy = silk_RSHIFT( energy, silk_max_32( 24 - LZ, 0 ) ); |
| |
| frac_Q24 = silk_DIV32( psPLC->conc_energy, silk_max( energy, 1 ) ); |
| |
| gain_Q16 = silk_LSHIFT( silk_SQRT_APPROX( frac_Q24 ), 4 ); |
| slope_Q16 = silk_DIV32_16( ( (opus_int32)1 << 16 ) - gain_Q16, length ); |
| /* Make slope 4x steeper to avoid missing onsets after DTX */ |
| slope_Q16 = silk_LSHIFT( slope_Q16, 2 ); |
| |
| for( i = 0; i < length; i++ ) { |
| frame[ i ] = silk_SMULWB( gain_Q16, frame[ i ] ); |
| gain_Q16 += slope_Q16; |
| if( gain_Q16 > (opus_int32)1 << 16 ) { |
| break; |
| } |
| } |
| } |
| } |
| psPLC->last_frame_lost = 0; |
| } |
| } |