summaryrefslogtreecommitdiffstats
path: root/media/libopus/silk/NSQ.c
diff options
context:
space:
mode:
Diffstat (limited to 'media/libopus/silk/NSQ.c')
-rw-r--r--media/libopus/silk/NSQ.c437
1 files changed, 437 insertions, 0 deletions
diff --git a/media/libopus/silk/NSQ.c b/media/libopus/silk/NSQ.c
new file mode 100644
index 0000000000..45dd45ce8d
--- /dev/null
+++ b/media/libopus/silk/NSQ.c
@@ -0,0 +1,437 @@
+/***********************************************************************
+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 "NSQ.h"
+
+
+static OPUS_INLINE void silk_nsq_scale_states(
+ const silk_encoder_state *psEncC, /* I Encoder State */
+ silk_nsq_state *NSQ, /* I/O NSQ state */
+ const opus_int16 x16[], /* I input */
+ opus_int32 x_sc_Q10[], /* O input scaled with 1/Gain */
+ const opus_int16 sLTP[], /* I re-whitened LTP state in Q0 */
+ opus_int32 sLTP_Q15[], /* O LTP state matching scaled input */
+ opus_int subfr, /* I subframe number */
+ const opus_int LTP_scale_Q14, /* I */
+ const opus_int32 Gains_Q16[ MAX_NB_SUBFR ], /* I */
+ const opus_int pitchL[ MAX_NB_SUBFR ], /* I Pitch lag */
+ const opus_int signal_type /* I Signal type */
+);
+
+#if !defined(OPUS_X86_MAY_HAVE_SSE4_1)
+static OPUS_INLINE void silk_noise_shape_quantizer(
+ silk_nsq_state *NSQ, /* I/O NSQ state */
+ opus_int signalType, /* I Signal type */
+ const opus_int32 x_sc_Q10[], /* I */
+ opus_int8 pulses[], /* O */
+ opus_int16 xq[], /* O */
+ opus_int32 sLTP_Q15[], /* I/O LTP state */
+ const opus_int16 a_Q12[], /* I Short term prediction coefs */
+ const opus_int16 b_Q14[], /* I Long term prediction coefs */
+ const opus_int16 AR_shp_Q13[], /* I Noise shaping AR coefs */
+ opus_int lag, /* I Pitch lag */
+ opus_int32 HarmShapeFIRPacked_Q14, /* I */
+ opus_int Tilt_Q14, /* I Spectral tilt */
+ opus_int32 LF_shp_Q14, /* I */
+ opus_int32 Gain_Q16, /* I */
+ opus_int Lambda_Q10, /* I */
+ opus_int offset_Q10, /* I */
+ opus_int length, /* I Input length */
+ opus_int shapingLPCOrder, /* I Noise shaping AR filter order */
+ opus_int predictLPCOrder, /* I Prediction filter order */
+ int arch /* I Architecture */
+);
+#endif
+
+void silk_NSQ_c
+(
+ const silk_encoder_state *psEncC, /* I Encoder State */
+ silk_nsq_state *NSQ, /* I/O NSQ state */
+ SideInfoIndices *psIndices, /* I/O Quantization Indices */
+ const opus_int16 x16[], /* I Input */
+ opus_int8 pulses[], /* O Quantized pulse signal */
+ const opus_int16 PredCoef_Q12[ 2 * MAX_LPC_ORDER ], /* I Short term prediction coefs */
+ const opus_int16 LTPCoef_Q14[ LTP_ORDER * MAX_NB_SUBFR ], /* I Long term prediction coefs */
+ const opus_int16 AR_Q13[ MAX_NB_SUBFR * MAX_SHAPE_LPC_ORDER ], /* I Noise shaping coefs */
+ const opus_int HarmShapeGain_Q14[ MAX_NB_SUBFR ], /* I Long term shaping coefs */
+ const opus_int Tilt_Q14[ MAX_NB_SUBFR ], /* I Spectral tilt */
+ const opus_int32 LF_shp_Q14[ MAX_NB_SUBFR ], /* I Low frequency shaping coefs */
+ const opus_int32 Gains_Q16[ MAX_NB_SUBFR ], /* I Quantization step sizes */
+ const opus_int pitchL[ MAX_NB_SUBFR ], /* I Pitch lags */
+ const opus_int Lambda_Q10, /* I Rate/distortion tradeoff */
+ const opus_int LTP_scale_Q14 /* I LTP state scaling */
+)
+{
+ opus_int k, lag, start_idx, LSF_interpolation_flag;
+ const opus_int16 *A_Q12, *B_Q14, *AR_shp_Q13;
+ opus_int16 *pxq;
+ VARDECL( opus_int32, sLTP_Q15 );
+ VARDECL( opus_int16, sLTP );
+ opus_int32 HarmShapeFIRPacked_Q14;
+ opus_int offset_Q10;
+ VARDECL( opus_int32, x_sc_Q10 );
+ SAVE_STACK;
+
+ NSQ->rand_seed = psIndices->Seed;
+
+ /* Set unvoiced lag to the previous one, overwrite later for voiced */
+ lag = NSQ->lagPrev;
+
+ silk_assert( NSQ->prev_gain_Q16 != 0 );
+
+ offset_Q10 = silk_Quantization_Offsets_Q10[ psIndices->signalType >> 1 ][ psIndices->quantOffsetType ];
+
+ if( psIndices->NLSFInterpCoef_Q2 == 4 ) {
+ LSF_interpolation_flag = 0;
+ } else {
+ LSF_interpolation_flag = 1;
+ }
+
+ ALLOC( sLTP_Q15, psEncC->ltp_mem_length + psEncC->frame_length, opus_int32 );
+ ALLOC( sLTP, psEncC->ltp_mem_length + psEncC->frame_length, opus_int16 );
+ ALLOC( x_sc_Q10, psEncC->subfr_length, opus_int32 );
+ /* Set up pointers to start of sub frame */
+ NSQ->sLTP_shp_buf_idx = psEncC->ltp_mem_length;
+ NSQ->sLTP_buf_idx = psEncC->ltp_mem_length;
+ pxq = &NSQ->xq[ psEncC->ltp_mem_length ];
+ for( k = 0; k < psEncC->nb_subfr; k++ ) {
+ A_Q12 = &PredCoef_Q12[ (( k >> 1 ) | ( 1 - LSF_interpolation_flag )) * MAX_LPC_ORDER ];
+ B_Q14 = &LTPCoef_Q14[ k * LTP_ORDER ];
+ AR_shp_Q13 = &AR_Q13[ k * MAX_SHAPE_LPC_ORDER ];
+
+ /* Noise shape parameters */
+ silk_assert( HarmShapeGain_Q14[ k ] >= 0 );
+ HarmShapeFIRPacked_Q14 = silk_RSHIFT( HarmShapeGain_Q14[ k ], 2 );
+ HarmShapeFIRPacked_Q14 |= silk_LSHIFT( (opus_int32)silk_RSHIFT( HarmShapeGain_Q14[ k ], 1 ), 16 );
+
+ NSQ->rewhite_flag = 0;
+ if( psIndices->signalType == TYPE_VOICED ) {
+ /* Voiced */
+ lag = pitchL[ k ];
+
+ /* Re-whitening */
+ if( ( k & ( 3 - silk_LSHIFT( LSF_interpolation_flag, 1 ) ) ) == 0 ) {
+ /* Rewhiten with new A coefs */
+ start_idx = psEncC->ltp_mem_length - lag - psEncC->predictLPCOrder - LTP_ORDER / 2;
+ celt_assert( start_idx > 0 );
+
+ silk_LPC_analysis_filter( &sLTP[ start_idx ], &NSQ->xq[ start_idx + k * psEncC->subfr_length ],
+ A_Q12, psEncC->ltp_mem_length - start_idx, psEncC->predictLPCOrder, psEncC->arch );
+
+ NSQ->rewhite_flag = 1;
+ NSQ->sLTP_buf_idx = psEncC->ltp_mem_length;
+ }
+ }
+
+ silk_nsq_scale_states( psEncC, NSQ, x16, x_sc_Q10, sLTP, sLTP_Q15, k, LTP_scale_Q14, Gains_Q16, pitchL, psIndices->signalType );
+
+ silk_noise_shape_quantizer( NSQ, psIndices->signalType, x_sc_Q10, pulses, pxq, sLTP_Q15, A_Q12, B_Q14,
+ AR_shp_Q13, lag, HarmShapeFIRPacked_Q14, Tilt_Q14[ k ], LF_shp_Q14[ k ], Gains_Q16[ k ], Lambda_Q10,
+ offset_Q10, psEncC->subfr_length, psEncC->shapingLPCOrder, psEncC->predictLPCOrder, psEncC->arch );
+
+ x16 += psEncC->subfr_length;
+ pulses += psEncC->subfr_length;
+ pxq += psEncC->subfr_length;
+ }
+
+ /* Update lagPrev for next frame */
+ NSQ->lagPrev = pitchL[ psEncC->nb_subfr - 1 ];
+
+ /* Save quantized speech and noise shaping signals */
+ silk_memmove( NSQ->xq, &NSQ->xq[ psEncC->frame_length ], psEncC->ltp_mem_length * sizeof( opus_int16 ) );
+ silk_memmove( NSQ->sLTP_shp_Q14, &NSQ->sLTP_shp_Q14[ psEncC->frame_length ], psEncC->ltp_mem_length * sizeof( opus_int32 ) );
+ RESTORE_STACK;
+}
+
+/******************************/
+/* silk_noise_shape_quantizer */
+/******************************/
+
+#if !defined(OPUS_X86_MAY_HAVE_SSE4_1)
+static OPUS_INLINE
+#endif
+void silk_noise_shape_quantizer(
+ silk_nsq_state *NSQ, /* I/O NSQ state */
+ opus_int signalType, /* I Signal type */
+ const opus_int32 x_sc_Q10[], /* I */
+ opus_int8 pulses[], /* O */
+ opus_int16 xq[], /* O */
+ opus_int32 sLTP_Q15[], /* I/O LTP state */
+ const opus_int16 a_Q12[], /* I Short term prediction coefs */
+ const opus_int16 b_Q14[], /* I Long term prediction coefs */
+ const opus_int16 AR_shp_Q13[], /* I Noise shaping AR coefs */
+ opus_int lag, /* I Pitch lag */
+ opus_int32 HarmShapeFIRPacked_Q14, /* I */
+ opus_int Tilt_Q14, /* I Spectral tilt */
+ opus_int32 LF_shp_Q14, /* I */
+ opus_int32 Gain_Q16, /* I */
+ opus_int Lambda_Q10, /* I */
+ opus_int offset_Q10, /* I */
+ opus_int length, /* I Input length */
+ opus_int shapingLPCOrder, /* I Noise shaping AR filter order */
+ opus_int predictLPCOrder, /* I Prediction filter order */
+ int arch /* I Architecture */
+)
+{
+ opus_int i;
+ opus_int32 LTP_pred_Q13, LPC_pred_Q10, n_AR_Q12, n_LTP_Q13;
+ opus_int32 n_LF_Q12, r_Q10, rr_Q10, q1_Q0, q1_Q10, q2_Q10, rd1_Q20, rd2_Q20;
+ opus_int32 exc_Q14, LPC_exc_Q14, xq_Q14, Gain_Q10;
+ opus_int32 tmp1, tmp2, sLF_AR_shp_Q14;
+ opus_int32 *psLPC_Q14, *shp_lag_ptr, *pred_lag_ptr;
+#ifdef silk_short_prediction_create_arch_coef
+ opus_int32 a_Q12_arch[MAX_LPC_ORDER];
+#endif
+
+ shp_lag_ptr = &NSQ->sLTP_shp_Q14[ NSQ->sLTP_shp_buf_idx - lag + HARM_SHAPE_FIR_TAPS / 2 ];
+ pred_lag_ptr = &sLTP_Q15[ NSQ->sLTP_buf_idx - lag + LTP_ORDER / 2 ];
+ Gain_Q10 = silk_RSHIFT( Gain_Q16, 6 );
+
+ /* Set up short term AR state */
+ psLPC_Q14 = &NSQ->sLPC_Q14[ NSQ_LPC_BUF_LENGTH - 1 ];
+
+#ifdef silk_short_prediction_create_arch_coef
+ silk_short_prediction_create_arch_coef(a_Q12_arch, a_Q12, predictLPCOrder);
+#endif
+
+ for( i = 0; i < length; i++ ) {
+ /* Generate dither */
+ NSQ->rand_seed = silk_RAND( NSQ->rand_seed );
+
+ /* Short-term prediction */
+ LPC_pred_Q10 = silk_noise_shape_quantizer_short_prediction(psLPC_Q14, a_Q12, a_Q12_arch, predictLPCOrder, arch);
+
+ /* Long-term prediction */
+ if( signalType == TYPE_VOICED ) {
+ /* 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++;
+ } else {
+ LTP_pred_Q13 = 0;
+ }
+
+ /* Noise shape feedback */
+ celt_assert( ( shapingLPCOrder & 1 ) == 0 ); /* check that order is even */
+ n_AR_Q12 = silk_NSQ_noise_shape_feedback_loop(&NSQ->sDiff_shp_Q14, NSQ->sAR2_Q14, AR_shp_Q13, shapingLPCOrder, arch);
+
+ n_AR_Q12 = silk_SMLAWB( n_AR_Q12, NSQ->sLF_AR_shp_Q14, Tilt_Q14 );
+
+ n_LF_Q12 = silk_SMULWB( NSQ->sLTP_shp_Q14[ NSQ->sLTP_shp_buf_idx - 1 ], LF_shp_Q14 );
+ n_LF_Q12 = silk_SMLAWT( n_LF_Q12, NSQ->sLF_AR_shp_Q14, LF_shp_Q14 );
+
+ celt_assert( lag > 0 || signalType != TYPE_VOICED );
+
+ /* Combine prediction and noise shaping signals */
+ tmp1 = silk_SUB32( silk_LSHIFT32( LPC_pred_Q10, 2 ), n_AR_Q12 ); /* Q12 */
+ tmp1 = silk_SUB32( tmp1, n_LF_Q12 ); /* Q12 */
+ if( lag > 0 ) {
+ /* Symmetric, packed FIR coefficients */
+ n_LTP_Q13 = silk_SMULWB( silk_ADD_SAT32( shp_lag_ptr[ 0 ], shp_lag_ptr[ -2 ] ), HarmShapeFIRPacked_Q14 );
+ n_LTP_Q13 = silk_SMLAWT( n_LTP_Q13, shp_lag_ptr[ -1 ], HarmShapeFIRPacked_Q14 );
+ n_LTP_Q13 = silk_LSHIFT( n_LTP_Q13, 1 );
+ shp_lag_ptr++;
+
+ tmp2 = silk_SUB32( LTP_pred_Q13, n_LTP_Q13 ); /* Q13 */
+ tmp1 = silk_ADD_LSHIFT32( tmp2, tmp1, 1 ); /* Q13 */
+ tmp1 = silk_RSHIFT_ROUND( tmp1, 3 ); /* Q10 */
+ } else {
+ tmp1 = silk_RSHIFT_ROUND( tmp1, 2 ); /* Q10 */
+ }
+
+ r_Q10 = silk_SUB32( x_sc_Q10[ i ], tmp1 ); /* residual error Q10 */
+
+ /* Flip sign depending on dither */
+ if( NSQ->rand_seed < 0 ) {
+ r_Q10 = -r_Q10;
+ }
+ r_Q10 = silk_LIMIT_32( r_Q10, -(31 << 10), 30 << 10 );
+
+ /* Find two quantization level candidates and measure their rate-distortion */
+ q1_Q10 = silk_SUB32( r_Q10, offset_Q10 );
+ q1_Q0 = silk_RSHIFT( q1_Q10, 10 );
+ if (Lambda_Q10 > 2048) {
+ /* For aggressive RDO, the bias becomes more than one pulse. */
+ int rdo_offset = Lambda_Q10/2 - 512;
+ if (q1_Q10 > rdo_offset) {
+ q1_Q0 = silk_RSHIFT( q1_Q10 - rdo_offset, 10 );
+ } else if (q1_Q10 < -rdo_offset) {
+ q1_Q0 = silk_RSHIFT( q1_Q10 + rdo_offset, 10 );
+ } else if (q1_Q10 < 0) {
+ q1_Q0 = -1;
+ } else {
+ q1_Q0 = 0;
+ }
+ }
+ if( q1_Q0 > 0 ) {
+ q1_Q10 = silk_SUB32( silk_LSHIFT( q1_Q0, 10 ), QUANT_LEVEL_ADJUST_Q10 );
+ q1_Q10 = silk_ADD32( q1_Q10, offset_Q10 );
+ q2_Q10 = silk_ADD32( q1_Q10, 1024 );
+ rd1_Q20 = silk_SMULBB( q1_Q10, Lambda_Q10 );
+ rd2_Q20 = silk_SMULBB( q2_Q10, Lambda_Q10 );
+ } else if( q1_Q0 == 0 ) {
+ q1_Q10 = offset_Q10;
+ q2_Q10 = silk_ADD32( q1_Q10, 1024 - QUANT_LEVEL_ADJUST_Q10 );
+ rd1_Q20 = silk_SMULBB( q1_Q10, Lambda_Q10 );
+ rd2_Q20 = silk_SMULBB( q2_Q10, Lambda_Q10 );
+ } else if( q1_Q0 == -1 ) {
+ q2_Q10 = offset_Q10;
+ q1_Q10 = silk_SUB32( q2_Q10, 1024 - QUANT_LEVEL_ADJUST_Q10 );
+ rd1_Q20 = silk_SMULBB( -q1_Q10, Lambda_Q10 );
+ rd2_Q20 = silk_SMULBB( q2_Q10, Lambda_Q10 );
+ } else { /* Q1_Q0 < -1 */
+ q1_Q10 = silk_ADD32( silk_LSHIFT( q1_Q0, 10 ), QUANT_LEVEL_ADJUST_Q10 );
+ q1_Q10 = silk_ADD32( q1_Q10, offset_Q10 );
+ q2_Q10 = silk_ADD32( q1_Q10, 1024 );
+ rd1_Q20 = silk_SMULBB( -q1_Q10, Lambda_Q10 );
+ rd2_Q20 = silk_SMULBB( -q2_Q10, Lambda_Q10 );
+ }
+ rr_Q10 = silk_SUB32( r_Q10, q1_Q10 );
+ rd1_Q20 = silk_SMLABB( rd1_Q20, rr_Q10, rr_Q10 );
+ rr_Q10 = silk_SUB32( r_Q10, q2_Q10 );
+ rd2_Q20 = silk_SMLABB( rd2_Q20, rr_Q10, rr_Q10 );
+
+ if( rd2_Q20 < rd1_Q20 ) {
+ q1_Q10 = q2_Q10;
+ }
+
+ pulses[ i ] = (opus_int8)silk_RSHIFT_ROUND( q1_Q10, 10 );
+
+ /* Excitation */
+ exc_Q14 = silk_LSHIFT( q1_Q10, 4 );
+ if ( NSQ->rand_seed < 0 ) {
+ exc_Q14 = -exc_Q14;
+ }
+
+ /* Add predictions */
+ LPC_exc_Q14 = silk_ADD_LSHIFT32( exc_Q14, LTP_pred_Q13, 1 );
+ xq_Q14 = silk_ADD_LSHIFT32( LPC_exc_Q14, LPC_pred_Q10, 4 );
+
+ /* Scale XQ back to normal level before saving */
+ xq[ i ] = (opus_int16)silk_SAT16( silk_RSHIFT_ROUND( silk_SMULWW( xq_Q14, Gain_Q10 ), 8 ) );
+
+ /* Update states */
+ psLPC_Q14++;
+ *psLPC_Q14 = xq_Q14;
+ NSQ->sDiff_shp_Q14 = silk_SUB_LSHIFT32( xq_Q14, x_sc_Q10[ i ], 4 );
+ sLF_AR_shp_Q14 = silk_SUB_LSHIFT32( NSQ->sDiff_shp_Q14, n_AR_Q12, 2 );
+ NSQ->sLF_AR_shp_Q14 = sLF_AR_shp_Q14;
+
+ NSQ->sLTP_shp_Q14[ NSQ->sLTP_shp_buf_idx ] = silk_SUB_LSHIFT32( sLF_AR_shp_Q14, n_LF_Q12, 2 );
+ sLTP_Q15[ NSQ->sLTP_buf_idx ] = silk_LSHIFT( LPC_exc_Q14, 1 );
+ NSQ->sLTP_shp_buf_idx++;
+ NSQ->sLTP_buf_idx++;
+
+ /* Make dither dependent on quantized signal */
+ NSQ->rand_seed = silk_ADD32_ovflw( NSQ->rand_seed, pulses[ i ] );
+ }
+
+ /* Update LPC synth buffer */
+ silk_memcpy( NSQ->sLPC_Q14, &NSQ->sLPC_Q14[ length ], NSQ_LPC_BUF_LENGTH * sizeof( opus_int32 ) );
+}
+
+static OPUS_INLINE void silk_nsq_scale_states(
+ const silk_encoder_state *psEncC, /* I Encoder State */
+ silk_nsq_state *NSQ, /* I/O NSQ state */
+ const opus_int16 x16[], /* I input */
+ opus_int32 x_sc_Q10[], /* O input scaled with 1/Gain */
+ const opus_int16 sLTP[], /* I re-whitened LTP state in Q0 */
+ opus_int32 sLTP_Q15[], /* O LTP state matching scaled input */
+ opus_int subfr, /* I subframe number */
+ const opus_int LTP_scale_Q14, /* I */
+ const opus_int32 Gains_Q16[ MAX_NB_SUBFR ], /* I */
+ const opus_int pitchL[ MAX_NB_SUBFR ], /* I Pitch lag */
+ const opus_int signal_type /* I Signal type */
+)
+{
+ opus_int i, lag;
+ opus_int32 gain_adj_Q16, inv_gain_Q31, inv_gain_Q26;
+
+ lag = pitchL[ subfr ];
+ inv_gain_Q31 = silk_INVERSE32_varQ( silk_max( Gains_Q16[ subfr ], 1 ), 47 );
+ silk_assert( inv_gain_Q31 != 0 );
+
+ /* Scale input */
+ inv_gain_Q26 = silk_RSHIFT_ROUND( inv_gain_Q31, 5 );
+ for( i = 0; i < psEncC->subfr_length; i++ ) {
+ x_sc_Q10[ i ] = silk_SMULWW( x16[ i ], inv_gain_Q26 );
+ }
+
+ /* After rewhitening the LTP state is un-scaled, so scale with inv_gain_Q16 */
+ if( NSQ->rewhite_flag ) {
+ if( subfr == 0 ) {
+ /* Do LTP downscaling */
+ inv_gain_Q31 = silk_LSHIFT( silk_SMULWB( inv_gain_Q31, LTP_scale_Q14 ), 2 );
+ }
+ for( i = NSQ->sLTP_buf_idx - lag - LTP_ORDER / 2; i < NSQ->sLTP_buf_idx; i++ ) {
+ silk_assert( i < MAX_FRAME_LENGTH );
+ sLTP_Q15[ i ] = silk_SMULWB( inv_gain_Q31, sLTP[ i ] );
+ }
+ }
+
+ /* Adjust for changing gain */
+ if( Gains_Q16[ subfr ] != NSQ->prev_gain_Q16 ) {
+ gain_adj_Q16 = silk_DIV32_varQ( NSQ->prev_gain_Q16, Gains_Q16[ subfr ], 16 );
+
+ /* Scale long-term shaping state */
+ for( i = NSQ->sLTP_shp_buf_idx - psEncC->ltp_mem_length; i < NSQ->sLTP_shp_buf_idx; i++ ) {
+ NSQ->sLTP_shp_Q14[ i ] = silk_SMULWW( gain_adj_Q16, NSQ->sLTP_shp_Q14[ i ] );
+ }
+
+ /* Scale long-term prediction state */
+ if( signal_type == TYPE_VOICED && NSQ->rewhite_flag == 0 ) {
+ for( i = NSQ->sLTP_buf_idx - lag - LTP_ORDER / 2; i < NSQ->sLTP_buf_idx; i++ ) {
+ sLTP_Q15[ i ] = silk_SMULWW( gain_adj_Q16, sLTP_Q15[ i ] );
+ }
+ }
+
+ NSQ->sLF_AR_shp_Q14 = silk_SMULWW( gain_adj_Q16, NSQ->sLF_AR_shp_Q14 );
+ NSQ->sDiff_shp_Q14 = silk_SMULWW( gain_adj_Q16, NSQ->sDiff_shp_Q14 );
+
+ /* Scale short-term prediction and shaping states */
+ for( i = 0; i < NSQ_LPC_BUF_LENGTH; i++ ) {
+ NSQ->sLPC_Q14[ i ] = silk_SMULWW( gain_adj_Q16, NSQ->sLPC_Q14[ i ] );
+ }
+ for( i = 0; i < MAX_SHAPE_LPC_ORDER; i++ ) {
+ NSQ->sAR2_Q14[ i ] = silk_SMULWW( gain_adj_Q16, NSQ->sAR2_Q14[ i ] );
+ }
+
+ /* Save inverse gain */
+ NSQ->prev_gain_Q16 = Gains_Q16[ subfr ];
+ }
+}