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Diffstat (limited to 'thirdparty/opus/silk/PLC.c')
| -rw-r--r-- | thirdparty/opus/silk/PLC.c | 445 | 
1 files changed, 445 insertions, 0 deletions
diff --git a/thirdparty/opus/silk/PLC.c b/thirdparty/opus/silk/PLC.c new file mode 100644 index 0000000000..34a94bc313 --- /dev/null +++ b/thirdparty/opus/silk/PLC.c @@ -0,0 +1,445 @@ +/*********************************************************************** +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 OPUS_INLINE void silk_PLC_update( +    silk_decoder_state                  *psDec,             /* I/O Decoder state        */ +    silk_decoder_control                *psDecCtrl          /* I/O Decoder control      */ +); + +static OPUS_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    */ +    int                                 arch                /* I  Run-time architecture */ +); + + +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              */ +    int                                 arch                /* I Run-time architecture  */ +) +{ +    /* 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, arch ); + +        psDec->lossCnt++; +    } else { +        /****************************/ +        /* Update state             */ +        /****************************/ +        silk_PLC_update( psDec, psDecCtrl ); +    } +} + +/**************************************************/ +/* Update state of PLC                            */ +/**************************************************/ +static OPUS_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 OPUS_INLINE void silk_PLC_energy(opus_int32 *energy1, opus_int *shift1, opus_int32 *energy2, opus_int *shift2, +      const opus_int32 *exc_Q14, const opus_int32 *prevGain_Q10, int subfr_length, int nb_subfr) +{ +    int i, k; +    VARDECL( opus_int16, exc_buf ); +    opus_int16 *exc_buf_ptr; +    SAVE_STACK; +    ALLOC( exc_buf, 2*subfr_length, opus_int16 ); +    /* Find random noise component */ +    /* Scale previous excitation signal */ +    exc_buf_ptr = exc_buf; +    for( k = 0; k < 2; k++ ) { +        for( i = 0; i < subfr_length; i++ ) { +            exc_buf_ptr[ i ] = (opus_int16)silk_SAT16( silk_RSHIFT( +                silk_SMULWW( exc_Q14[ i + ( k + nb_subfr - 2 ) * subfr_length ], prevGain_Q10[ k ] ), 8 ) ); +        } +        exc_buf_ptr += 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,                  subfr_length ); +    silk_sum_sqr_shift( energy2, shift2, &exc_buf[ subfr_length ], subfr_length ); +    RESTORE_STACK; +} + +static OPUS_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    */ +    int                                 arch                /* I Run-time architecture  */ +) +{ +    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; +    opus_int32 *sLPC_Q14_ptr; +    opus_int16 A_Q12[ MAX_LPC_ORDER ]; +#ifdef SMALL_FOOTPRINT +    opus_int16 *sLTP; +#else +    VARDECL( opus_int16, sLTP ); +#endif +    VARDECL( opus_int32, sLTP_Q14 ); +    silk_PLC_struct *psPLC = &psDec->sPLC; +    opus_int32 prevGain_Q10[2]; +    SAVE_STACK; + +    ALLOC( sLTP_Q14, psDec->ltp_mem_length + psDec->frame_length, opus_int32 ); +#ifdef SMALL_FOOTPRINT +    /* Ugly hack that breaks aliasing rules to save stack: put sLTP at the very end of sLTP_Q14. */ +    sLTP = ((opus_int16*)&sLTP_Q14[psDec->ltp_mem_length + psDec->frame_length])-psDec->ltp_mem_length; +#else +    ALLOC( sLTP, psDec->ltp_mem_length, opus_int16 ); +#endif + +    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 ) ); +    } + +    silk_PLC_energy(&energy1, &shift1, &energy2, &shift2, psDec->exc_Q14, prevGain_Q10, psDec->subfr_length, psDec->nb_subfr); + +    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, arch ); +    /* 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; +    } +}  |