| /*********************************************************************** |
| 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" |
| |
| /**********************************************************/ |
| /* Core decoder. Performs inverse NSQ operation LTP + LPC */ |
| /**********************************************************/ |
| void silk_decode_core( |
| silk_decoder_state *psDec, /* I/O Decoder state */ |
| silk_decoder_control *psDecCtrl, /* I Decoder control */ |
| opus_int16 xq[], /* O Decoded speech */ |
| const opus_int16 pulses[ MAX_FRAME_LENGTH ], /* I Pulse signal */ |
| int arch /* I Run-time architecture */ |
| ) |
| { |
| opus_int i, k, lag = 0, start_idx, sLTP_buf_idx, NLSF_interpolation_flag, signalType; |
| opus_int16 *A_Q12, *B_Q14, *pxq, A_Q12_tmp[ MAX_LPC_ORDER ]; |
| VARDECL( opus_int16, sLTP ); |
| VARDECL( opus_int32, sLTP_Q15 ); |
| opus_int32 LTP_pred_Q13, LPC_pred_Q10, Gain_Q10, inv_gain_Q31, gain_adj_Q16, rand_seed, offset_Q10; |
| opus_int32 *pred_lag_ptr, *pexc_Q14, *pres_Q14; |
| VARDECL( opus_int32, res_Q14 ); |
| VARDECL( opus_int32, sLPC_Q14 ); |
| SAVE_STACK; |
| |
| silk_assert( psDec->prev_gain_Q16 != 0 ); |
| |
| ALLOC( sLTP, psDec->ltp_mem_length, opus_int16 ); |
| ALLOC( sLTP_Q15, psDec->ltp_mem_length + psDec->frame_length, opus_int32 ); |
| ALLOC( res_Q14, psDec->subfr_length, opus_int32 ); |
| ALLOC( sLPC_Q14, psDec->subfr_length + MAX_LPC_ORDER, opus_int32 ); |
| |
| offset_Q10 = silk_Quantization_Offsets_Q10[ psDec->indices.signalType >> 1 ][ psDec->indices.quantOffsetType ]; |
| |
| if( psDec->indices.NLSFInterpCoef_Q2 < 1 << 2 ) { |
| NLSF_interpolation_flag = 1; |
| } else { |
| NLSF_interpolation_flag = 0; |
| } |
| |
| /* Decode excitation */ |
| rand_seed = psDec->indices.Seed; |
| for( i = 0; i < psDec->frame_length; i++ ) { |
| rand_seed = silk_RAND( rand_seed ); |
| psDec->exc_Q14[ i ] = silk_LSHIFT( (opus_int32)pulses[ i ], 14 ); |
| if( psDec->exc_Q14[ i ] > 0 ) { |
| psDec->exc_Q14[ i ] -= QUANT_LEVEL_ADJUST_Q10 << 4; |
| } else |
| if( psDec->exc_Q14[ i ] < 0 ) { |
| psDec->exc_Q14[ i ] += QUANT_LEVEL_ADJUST_Q10 << 4; |
| } |
| psDec->exc_Q14[ i ] += offset_Q10 << 4; |
| if( rand_seed < 0 ) { |
| psDec->exc_Q14[ i ] = -psDec->exc_Q14[ i ]; |
| } |
| |
| rand_seed = silk_ADD32_ovflw( rand_seed, pulses[ i ] ); |
| } |
| |
| /* Copy LPC state */ |
| silk_memcpy( sLPC_Q14, psDec->sLPC_Q14_buf, MAX_LPC_ORDER * sizeof( opus_int32 ) ); |
| |
| pexc_Q14 = psDec->exc_Q14; |
| pxq = xq; |
| sLTP_buf_idx = psDec->ltp_mem_length; |
| /* Loop over subframes */ |
| for( k = 0; k < psDec->nb_subfr; k++ ) { |
| pres_Q14 = res_Q14; |
| A_Q12 = psDecCtrl->PredCoef_Q12[ k >> 1 ]; |
| |
| /* Preload LPC coeficients to array on stack. Gives small performance gain */ |
| silk_memcpy( A_Q12_tmp, A_Q12, psDec->LPC_order * sizeof( opus_int16 ) ); |
| B_Q14 = &psDecCtrl->LTPCoef_Q14[ k * LTP_ORDER ]; |
| signalType = psDec->indices.signalType; |
| |
| Gain_Q10 = silk_RSHIFT( psDecCtrl->Gains_Q16[ k ], 6 ); |
| inv_gain_Q31 = silk_INVERSE32_varQ( psDecCtrl->Gains_Q16[ k ], 47 ); |
| |
| /* Calculate gain adjustment factor */ |
| if( psDecCtrl->Gains_Q16[ k ] != psDec->prev_gain_Q16 ) { |
| gain_adj_Q16 = silk_DIV32_varQ( psDec->prev_gain_Q16, psDecCtrl->Gains_Q16[ k ], 16 ); |
| |
| /* Scale short term state */ |
| for( i = 0; i < MAX_LPC_ORDER; i++ ) { |
| sLPC_Q14[ i ] = silk_SMULWW( gain_adj_Q16, sLPC_Q14[ i ] ); |
| } |
| } else { |
| gain_adj_Q16 = (opus_int32)1 << 16; |
| } |
| |
| /* Save inv_gain */ |
| silk_assert( inv_gain_Q31 != 0 ); |
| psDec->prev_gain_Q16 = psDecCtrl->Gains_Q16[ k ]; |
| |
| /* Avoid abrupt transition from voiced PLC to unvoiced normal decoding */ |
| if( psDec->lossCnt && psDec->prevSignalType == TYPE_VOICED && |
| psDec->indices.signalType != TYPE_VOICED && k < MAX_NB_SUBFR/2 ) { |
| |
| silk_memset( B_Q14, 0, LTP_ORDER * sizeof( opus_int16 ) ); |
| B_Q14[ LTP_ORDER/2 ] = SILK_FIX_CONST( 0.25, 14 ); |
| |
| signalType = TYPE_VOICED; |
| psDecCtrl->pitchL[ k ] = psDec->lagPrev; |
| } |
| |
| if( signalType == TYPE_VOICED ) { |
| /* Voiced */ |
| lag = psDecCtrl->pitchL[ k ]; |
| |
| /* Re-whitening */ |
| if( k == 0 || ( k == 2 && NLSF_interpolation_flag ) ) { |
| /* Rewhiten with new A coefs */ |
| start_idx = psDec->ltp_mem_length - lag - psDec->LPC_order - LTP_ORDER / 2; |
| celt_assert( start_idx > 0 ); |
| |
| if( k == 2 ) { |
| silk_memcpy( &psDec->outBuf[ psDec->ltp_mem_length ], xq, 2 * psDec->subfr_length * sizeof( opus_int16 ) ); |
| } |
| |
| silk_LPC_analysis_filter( &sLTP[ start_idx ], &psDec->outBuf[ start_idx + k * psDec->subfr_length ], |
| A_Q12, psDec->ltp_mem_length - start_idx, psDec->LPC_order, arch ); |
| |
| /* After rewhitening the LTP state is unscaled */ |
| if( k == 0 ) { |
| /* Do LTP downscaling to reduce inter-packet dependency */ |
| inv_gain_Q31 = silk_LSHIFT( silk_SMULWB( inv_gain_Q31, psDecCtrl->LTP_scale_Q14 ), 2 ); |
| } |
| for( i = 0; i < lag + LTP_ORDER/2; i++ ) { |
| sLTP_Q15[ sLTP_buf_idx - i - 1 ] = silk_SMULWB( inv_gain_Q31, sLTP[ psDec->ltp_mem_length - i - 1 ] ); |
| } |
| } else { |
| /* Update LTP state when Gain changes */ |
| if( gain_adj_Q16 != (opus_int32)1 << 16 ) { |
| for( i = 0; i < lag + LTP_ORDER/2; i++ ) { |
| sLTP_Q15[ sLTP_buf_idx - i - 1 ] = silk_SMULWW( gain_adj_Q16, sLTP_Q15[ sLTP_buf_idx - i - 1 ] ); |
| } |
| } |
| } |
| } |
| |
| /* Long-term prediction */ |
| if( signalType == TYPE_VOICED ) { |
| /* Set up pointer */ |
| pred_lag_ptr = &sLTP_Q15[ 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_Q13 = 2; |
| LTP_pred_Q13 = silk_SMLAWB( LTP_pred_Q13, pred_lag_ptr[ 0 ], B_Q14[ 0 ] ); |
| LTP_pred_Q13 = silk_SMLAWB( LTP_pred_Q13, pred_lag_ptr[ -1 ], B_Q14[ 1 ] ); |
| LTP_pred_Q13 = silk_SMLAWB( LTP_pred_Q13, pred_lag_ptr[ -2 ], B_Q14[ 2 ] ); |
| LTP_pred_Q13 = silk_SMLAWB( LTP_pred_Q13, pred_lag_ptr[ -3 ], B_Q14[ 3 ] ); |
| LTP_pred_Q13 = silk_SMLAWB( LTP_pred_Q13, pred_lag_ptr[ -4 ], B_Q14[ 4 ] ); |
| pred_lag_ptr++; |
| |
| /* Generate LPC excitation */ |
| pres_Q14[ i ] = silk_ADD_LSHIFT32( pexc_Q14[ i ], LTP_pred_Q13, 1 ); |
| |
| /* Update states */ |
| sLTP_Q15[ sLTP_buf_idx ] = silk_LSHIFT( pres_Q14[ i ], 1 ); |
| sLTP_buf_idx++; |
| } |
| } else { |
| pres_Q14 = pexc_Q14; |
| } |
| |
| for( i = 0; i < psDec->subfr_length; i++ ) { |
| /* Short-term prediction */ |
| celt_assert( psDec->LPC_order == 10 || psDec->LPC_order == 16 ); |
| /* 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[ MAX_LPC_ORDER + i - 1 ], A_Q12_tmp[ 0 ] ); |
| LPC_pred_Q10 = silk_SMLAWB( LPC_pred_Q10, sLPC_Q14[ MAX_LPC_ORDER + i - 2 ], A_Q12_tmp[ 1 ] ); |
| LPC_pred_Q10 = silk_SMLAWB( LPC_pred_Q10, sLPC_Q14[ MAX_LPC_ORDER + i - 3 ], A_Q12_tmp[ 2 ] ); |
| LPC_pred_Q10 = silk_SMLAWB( LPC_pred_Q10, sLPC_Q14[ MAX_LPC_ORDER + i - 4 ], A_Q12_tmp[ 3 ] ); |
| LPC_pred_Q10 = silk_SMLAWB( LPC_pred_Q10, sLPC_Q14[ MAX_LPC_ORDER + i - 5 ], A_Q12_tmp[ 4 ] ); |
| LPC_pred_Q10 = silk_SMLAWB( LPC_pred_Q10, sLPC_Q14[ MAX_LPC_ORDER + i - 6 ], A_Q12_tmp[ 5 ] ); |
| LPC_pred_Q10 = silk_SMLAWB( LPC_pred_Q10, sLPC_Q14[ MAX_LPC_ORDER + i - 7 ], A_Q12_tmp[ 6 ] ); |
| LPC_pred_Q10 = silk_SMLAWB( LPC_pred_Q10, sLPC_Q14[ MAX_LPC_ORDER + i - 8 ], A_Q12_tmp[ 7 ] ); |
| LPC_pred_Q10 = silk_SMLAWB( LPC_pred_Q10, sLPC_Q14[ MAX_LPC_ORDER + i - 9 ], A_Q12_tmp[ 8 ] ); |
| LPC_pred_Q10 = silk_SMLAWB( LPC_pred_Q10, sLPC_Q14[ MAX_LPC_ORDER + i - 10 ], A_Q12_tmp[ 9 ] ); |
| if( psDec->LPC_order == 16 ) { |
| LPC_pred_Q10 = silk_SMLAWB( LPC_pred_Q10, sLPC_Q14[ MAX_LPC_ORDER + i - 11 ], A_Q12_tmp[ 10 ] ); |
| LPC_pred_Q10 = silk_SMLAWB( LPC_pred_Q10, sLPC_Q14[ MAX_LPC_ORDER + i - 12 ], A_Q12_tmp[ 11 ] ); |
| LPC_pred_Q10 = silk_SMLAWB( LPC_pred_Q10, sLPC_Q14[ MAX_LPC_ORDER + i - 13 ], A_Q12_tmp[ 12 ] ); |
| LPC_pred_Q10 = silk_SMLAWB( LPC_pred_Q10, sLPC_Q14[ MAX_LPC_ORDER + i - 14 ], A_Q12_tmp[ 13 ] ); |
| LPC_pred_Q10 = silk_SMLAWB( LPC_pred_Q10, sLPC_Q14[ MAX_LPC_ORDER + i - 15 ], A_Q12_tmp[ 14 ] ); |
| LPC_pred_Q10 = silk_SMLAWB( LPC_pred_Q10, sLPC_Q14[ MAX_LPC_ORDER + i - 16 ], A_Q12_tmp[ 15 ] ); |
| } |
| |
| /* Add prediction to LPC excitation */ |
| sLPC_Q14[ MAX_LPC_ORDER + i ] = silk_ADD_SAT32( pres_Q14[ i ], silk_LSHIFT_SAT32( LPC_pred_Q10, 4 ) ); |
| |
| /* Scale with gain */ |
| pxq[ i ] = (opus_int16)silk_SAT16( silk_RSHIFT_ROUND( silk_SMULWW( sLPC_Q14[ MAX_LPC_ORDER + i ], Gain_Q10 ), 8 ) ); |
| } |
| |
| /* Update LPC filter state */ |
| silk_memcpy( sLPC_Q14, &sLPC_Q14[ psDec->subfr_length ], MAX_LPC_ORDER * sizeof( opus_int32 ) ); |
| pexc_Q14 += psDec->subfr_length; |
| pxq += psDec->subfr_length; |
| } |
| |
| /* Save LPC state */ |
| silk_memcpy( psDec->sLPC_Q14_buf, sLPC_Q14, MAX_LPC_ORDER * sizeof( opus_int32 ) ); |
| RESTORE_STACK; |
| } |
