1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/media/libopus/silk/CNG.c Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,172 @@
1.4 +/***********************************************************************
1.5 +Copyright (c) 2006-2011, Skype Limited. All rights reserved.
1.6 +Redistribution and use in source and binary forms, with or without
1.7 +modification, are permitted provided that the following conditions
1.8 +are met:
1.9 +- Redistributions of source code must retain the above copyright notice,
1.10 +this list of conditions and the following disclaimer.
1.11 +- Redistributions in binary form must reproduce the above copyright
1.12 +notice, this list of conditions and the following disclaimer in the
1.13 +documentation and/or other materials provided with the distribution.
1.14 +- Neither the name of Internet Society, IETF or IETF Trust, nor the
1.15 +names of specific contributors, may be used to endorse or promote
1.16 +products derived from this software without specific prior written
1.17 +permission.
1.18 +THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
1.19 +AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
1.20 +IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
1.21 +ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
1.22 +LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
1.23 +CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
1.24 +SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
1.25 +INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
1.26 +CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
1.27 +ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
1.28 +POSSIBILITY OF SUCH DAMAGE.
1.29 +***********************************************************************/
1.30 +
1.31 +#ifdef HAVE_CONFIG_H
1.32 +#include "config.h"
1.33 +#endif
1.34 +
1.35 +#include "main.h"
1.36 +#include "stack_alloc.h"
1.37 +
1.38 +/* Generates excitation for CNG LPC synthesis */
1.39 +static OPUS_INLINE void silk_CNG_exc(
1.40 + opus_int32 residual_Q10[], /* O CNG residual signal Q10 */
1.41 + opus_int32 exc_buf_Q14[], /* I Random samples buffer Q10 */
1.42 + opus_int32 Gain_Q16, /* I Gain to apply */
1.43 + opus_int length, /* I Length */
1.44 + opus_int32 *rand_seed /* I/O Seed to random index generator */
1.45 +)
1.46 +{
1.47 + opus_int32 seed;
1.48 + opus_int i, idx, exc_mask;
1.49 +
1.50 + exc_mask = CNG_BUF_MASK_MAX;
1.51 + while( exc_mask > length ) {
1.52 + exc_mask = silk_RSHIFT( exc_mask, 1 );
1.53 + }
1.54 +
1.55 + seed = *rand_seed;
1.56 + for( i = 0; i < length; i++ ) {
1.57 + seed = silk_RAND( seed );
1.58 + idx = (opus_int)( silk_RSHIFT( seed, 24 ) & exc_mask );
1.59 + silk_assert( idx >= 0 );
1.60 + silk_assert( idx <= CNG_BUF_MASK_MAX );
1.61 + residual_Q10[ i ] = (opus_int16)silk_SAT16( silk_SMULWW( exc_buf_Q14[ idx ], Gain_Q16 >> 4 ) );
1.62 + }
1.63 + *rand_seed = seed;
1.64 +}
1.65 +
1.66 +void silk_CNG_Reset(
1.67 + silk_decoder_state *psDec /* I/O Decoder state */
1.68 +)
1.69 +{
1.70 + opus_int i, NLSF_step_Q15, NLSF_acc_Q15;
1.71 +
1.72 + NLSF_step_Q15 = silk_DIV32_16( silk_int16_MAX, psDec->LPC_order + 1 );
1.73 + NLSF_acc_Q15 = 0;
1.74 + for( i = 0; i < psDec->LPC_order; i++ ) {
1.75 + NLSF_acc_Q15 += NLSF_step_Q15;
1.76 + psDec->sCNG.CNG_smth_NLSF_Q15[ i ] = NLSF_acc_Q15;
1.77 + }
1.78 + psDec->sCNG.CNG_smth_Gain_Q16 = 0;
1.79 + psDec->sCNG.rand_seed = 3176576;
1.80 +}
1.81 +
1.82 +/* Updates CNG estimate, and applies the CNG when packet was lost */
1.83 +void silk_CNG(
1.84 + silk_decoder_state *psDec, /* I/O Decoder state */
1.85 + silk_decoder_control *psDecCtrl, /* I/O Decoder control */
1.86 + opus_int16 frame[], /* I/O Signal */
1.87 + opus_int length /* I Length of residual */
1.88 +)
1.89 +{
1.90 + opus_int i, subfr;
1.91 + opus_int32 sum_Q6, max_Gain_Q16;
1.92 + opus_int16 A_Q12[ MAX_LPC_ORDER ];
1.93 + silk_CNG_struct *psCNG = &psDec->sCNG;
1.94 + SAVE_STACK;
1.95 +
1.96 + if( psDec->fs_kHz != psCNG->fs_kHz ) {
1.97 + /* Reset state */
1.98 + silk_CNG_Reset( psDec );
1.99 +
1.100 + psCNG->fs_kHz = psDec->fs_kHz;
1.101 + }
1.102 + if( psDec->lossCnt == 0 && psDec->prevSignalType == TYPE_NO_VOICE_ACTIVITY ) {
1.103 + /* Update CNG parameters */
1.104 +
1.105 + /* Smoothing of LSF's */
1.106 + for( i = 0; i < psDec->LPC_order; i++ ) {
1.107 + psCNG->CNG_smth_NLSF_Q15[ i ] += silk_SMULWB( (opus_int32)psDec->prevNLSF_Q15[ i ] - (opus_int32)psCNG->CNG_smth_NLSF_Q15[ i ], CNG_NLSF_SMTH_Q16 );
1.108 + }
1.109 + /* Find the subframe with the highest gain */
1.110 + max_Gain_Q16 = 0;
1.111 + subfr = 0;
1.112 + for( i = 0; i < psDec->nb_subfr; i++ ) {
1.113 + if( psDecCtrl->Gains_Q16[ i ] > max_Gain_Q16 ) {
1.114 + max_Gain_Q16 = psDecCtrl->Gains_Q16[ i ];
1.115 + subfr = i;
1.116 + }
1.117 + }
1.118 + /* Update CNG excitation buffer with excitation from this subframe */
1.119 + silk_memmove( &psCNG->CNG_exc_buf_Q14[ psDec->subfr_length ], psCNG->CNG_exc_buf_Q14, ( psDec->nb_subfr - 1 ) * psDec->subfr_length * sizeof( opus_int32 ) );
1.120 + silk_memcpy( psCNG->CNG_exc_buf_Q14, &psDec->exc_Q14[ subfr * psDec->subfr_length ], psDec->subfr_length * sizeof( opus_int32 ) );
1.121 +
1.122 + /* Smooth gains */
1.123 + for( i = 0; i < psDec->nb_subfr; i++ ) {
1.124 + psCNG->CNG_smth_Gain_Q16 += silk_SMULWB( psDecCtrl->Gains_Q16[ i ] - psCNG->CNG_smth_Gain_Q16, CNG_GAIN_SMTH_Q16 );
1.125 + }
1.126 + }
1.127 +
1.128 + /* Add CNG when packet is lost or during DTX */
1.129 + if( psDec->lossCnt ) {
1.130 + VARDECL( opus_int32, CNG_sig_Q10 );
1.131 +
1.132 + ALLOC( CNG_sig_Q10, length + MAX_LPC_ORDER, opus_int32 );
1.133 +
1.134 + /* Generate CNG excitation */
1.135 + silk_CNG_exc( CNG_sig_Q10 + MAX_LPC_ORDER, psCNG->CNG_exc_buf_Q14, psCNG->CNG_smth_Gain_Q16, length, &psCNG->rand_seed );
1.136 +
1.137 + /* Convert CNG NLSF to filter representation */
1.138 + silk_NLSF2A( A_Q12, psCNG->CNG_smth_NLSF_Q15, psDec->LPC_order );
1.139 +
1.140 + /* Generate CNG signal, by synthesis filtering */
1.141 + silk_memcpy( CNG_sig_Q10, psCNG->CNG_synth_state, MAX_LPC_ORDER * sizeof( opus_int32 ) );
1.142 + for( i = 0; i < length; i++ ) {
1.143 + silk_assert( psDec->LPC_order == 10 || psDec->LPC_order == 16 );
1.144 + /* Avoids introducing a bias because silk_SMLAWB() always rounds to -inf */
1.145 + sum_Q6 = silk_RSHIFT( psDec->LPC_order, 1 );
1.146 + sum_Q6 = silk_SMLAWB( sum_Q6, CNG_sig_Q10[ MAX_LPC_ORDER + i - 1 ], A_Q12[ 0 ] );
1.147 + sum_Q6 = silk_SMLAWB( sum_Q6, CNG_sig_Q10[ MAX_LPC_ORDER + i - 2 ], A_Q12[ 1 ] );
1.148 + sum_Q6 = silk_SMLAWB( sum_Q6, CNG_sig_Q10[ MAX_LPC_ORDER + i - 3 ], A_Q12[ 2 ] );
1.149 + sum_Q6 = silk_SMLAWB( sum_Q6, CNG_sig_Q10[ MAX_LPC_ORDER + i - 4 ], A_Q12[ 3 ] );
1.150 + sum_Q6 = silk_SMLAWB( sum_Q6, CNG_sig_Q10[ MAX_LPC_ORDER + i - 5 ], A_Q12[ 4 ] );
1.151 + sum_Q6 = silk_SMLAWB( sum_Q6, CNG_sig_Q10[ MAX_LPC_ORDER + i - 6 ], A_Q12[ 5 ] );
1.152 + sum_Q6 = silk_SMLAWB( sum_Q6, CNG_sig_Q10[ MAX_LPC_ORDER + i - 7 ], A_Q12[ 6 ] );
1.153 + sum_Q6 = silk_SMLAWB( sum_Q6, CNG_sig_Q10[ MAX_LPC_ORDER + i - 8 ], A_Q12[ 7 ] );
1.154 + sum_Q6 = silk_SMLAWB( sum_Q6, CNG_sig_Q10[ MAX_LPC_ORDER + i - 9 ], A_Q12[ 8 ] );
1.155 + sum_Q6 = silk_SMLAWB( sum_Q6, CNG_sig_Q10[ MAX_LPC_ORDER + i - 10 ], A_Q12[ 9 ] );
1.156 + if( psDec->LPC_order == 16 ) {
1.157 + sum_Q6 = silk_SMLAWB( sum_Q6, CNG_sig_Q10[ MAX_LPC_ORDER + i - 11 ], A_Q12[ 10 ] );
1.158 + sum_Q6 = silk_SMLAWB( sum_Q6, CNG_sig_Q10[ MAX_LPC_ORDER + i - 12 ], A_Q12[ 11 ] );
1.159 + sum_Q6 = silk_SMLAWB( sum_Q6, CNG_sig_Q10[ MAX_LPC_ORDER + i - 13 ], A_Q12[ 12 ] );
1.160 + sum_Q6 = silk_SMLAWB( sum_Q6, CNG_sig_Q10[ MAX_LPC_ORDER + i - 14 ], A_Q12[ 13 ] );
1.161 + sum_Q6 = silk_SMLAWB( sum_Q6, CNG_sig_Q10[ MAX_LPC_ORDER + i - 15 ], A_Q12[ 14 ] );
1.162 + sum_Q6 = silk_SMLAWB( sum_Q6, CNG_sig_Q10[ MAX_LPC_ORDER + i - 16 ], A_Q12[ 15 ] );
1.163 + }
1.164 +
1.165 + /* Update states */
1.166 + CNG_sig_Q10[ MAX_LPC_ORDER + i ] = silk_ADD_LSHIFT( CNG_sig_Q10[ MAX_LPC_ORDER + i ], sum_Q6, 4 );
1.167 +
1.168 + frame[ i ] = silk_ADD_SAT16( frame[ i ], silk_RSHIFT_ROUND( sum_Q6, 6 ) );
1.169 + }
1.170 + silk_memcpy( psCNG->CNG_synth_state, &CNG_sig_Q10[ length ], MAX_LPC_ORDER * sizeof( opus_int32 ) );
1.171 + } else {
1.172 + silk_memset( psCNG->CNG_synth_state, 0, psDec->LPC_order * sizeof( opus_int32 ) );
1.173 + }
1.174 + RESTORE_STACK;
1.175 +}
