1885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org/*********************************************************************** 2885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.orgCopyright (c) 2006-2011, Skype Limited. All rights reserved. 3885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.orgRedistribution and use in source and binary forms, with or without 4885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.orgmodification, are permitted provided that the following conditions 5885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.orgare met: 6885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org- Redistributions of source code must retain the above copyright notice, 7885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.orgthis list of conditions and the following disclaimer. 8885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org- Redistributions in binary form must reproduce the above copyright 9885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.orgnotice, this list of conditions and the following disclaimer in the 10885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.orgdocumentation and/or other materials provided with the distribution. 11e3ea049fcaee2247e45f0ce793d4313babb4ef69tlegrand@chromium.org- Neither the name of Internet Society, IETF or IETF Trust, nor the 12885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.orgnames of specific contributors, may be used to endorse or promote 13885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.orgproducts derived from this software without specific prior written 14885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.orgpermission. 15e3ea049fcaee2247e45f0ce793d4313babb4ef69tlegrand@chromium.orgTHIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 16885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.orgAND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.orgIMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.orgARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE 19885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.orgLIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 20885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.orgCONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 21885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.orgSUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 22885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.orgINTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 23885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.orgCONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 24885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.orgARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 25885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.orgPOSSIBILITY OF SUCH DAMAGE. 26885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org***********************************************************************/ 27885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org 28885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org#ifdef HAVE_CONFIG_H 29885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org#include "config.h" 30885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org#endif 31885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org 32885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org#include "main.h" 33e3ea049fcaee2247e45f0ce793d4313babb4ef69tlegrand@chromium.org#include "stack_alloc.h" 34885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org 35885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org/* Convert Left/Right stereo signal to adaptive Mid/Side representation */ 36885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.orgvoid silk_stereo_LR_to_MS( 37885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org stereo_enc_state *state, /* I/O State */ 38885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org opus_int16 x1[], /* I/O Left input signal, becomes mid signal */ 39885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org opus_int16 x2[], /* I/O Right input signal, becomes side signal */ 40885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org opus_int8 ix[ 2 ][ 3 ], /* O Quantization indices */ 41885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org opus_int8 *mid_only_flag, /* O Flag: only mid signal coded */ 42885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org opus_int32 mid_side_rates_bps[], /* O Bitrates for mid and side signals */ 43885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org opus_int32 total_rate_bps, /* I Total bitrate */ 44885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org opus_int prev_speech_act_Q8, /* I Speech activity level in previous frame */ 45885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org opus_int toMono, /* I Last frame before a stereo->mono transition */ 46885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org opus_int fs_kHz, /* I Sample rate (kHz) */ 47885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org opus_int frame_length /* I Number of samples */ 48885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org) 49885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org{ 50885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org opus_int n, is10msFrame, denom_Q16, delta0_Q13, delta1_Q13; 51885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org opus_int32 sum, diff, smooth_coef_Q16, pred_Q13[ 2 ], pred0_Q13, pred1_Q13; 52885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org opus_int32 LP_ratio_Q14, HP_ratio_Q14, frac_Q16, frac_3_Q16, min_mid_rate_bps, width_Q14, w_Q24, deltaw_Q24; 53e3ea049fcaee2247e45f0ce793d4313babb4ef69tlegrand@chromium.org VARDECL( opus_int16, side ); 54e3ea049fcaee2247e45f0ce793d4313babb4ef69tlegrand@chromium.org VARDECL( opus_int16, LP_mid ); 55e3ea049fcaee2247e45f0ce793d4313babb4ef69tlegrand@chromium.org VARDECL( opus_int16, HP_mid ); 56e3ea049fcaee2247e45f0ce793d4313babb4ef69tlegrand@chromium.org VARDECL( opus_int16, LP_side ); 57e3ea049fcaee2247e45f0ce793d4313babb4ef69tlegrand@chromium.org VARDECL( opus_int16, HP_side ); 58885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org opus_int16 *mid = &x1[ -2 ]; 59e3ea049fcaee2247e45f0ce793d4313babb4ef69tlegrand@chromium.org SAVE_STACK; 60885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org 61e3ea049fcaee2247e45f0ce793d4313babb4ef69tlegrand@chromium.org ALLOC( side, frame_length + 2, opus_int16 ); 62885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org /* Convert to basic mid/side signals */ 63885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org for( n = 0; n < frame_length + 2; n++ ) { 64885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org sum = x1[ n - 2 ] + (opus_int32)x2[ n - 2 ]; 65885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org diff = x1[ n - 2 ] - (opus_int32)x2[ n - 2 ]; 66885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org mid[ n ] = (opus_int16)silk_RSHIFT_ROUND( sum, 1 ); 67885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org side[ n ] = (opus_int16)silk_SAT16( silk_RSHIFT_ROUND( diff, 1 ) ); 68885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org } 69885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org 70885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org /* Buffering */ 71885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org silk_memcpy( mid, state->sMid, 2 * sizeof( opus_int16 ) ); 72885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org silk_memcpy( side, state->sSide, 2 * sizeof( opus_int16 ) ); 73885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org silk_memcpy( state->sMid, &mid[ frame_length ], 2 * sizeof( opus_int16 ) ); 74885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org silk_memcpy( state->sSide, &side[ frame_length ], 2 * sizeof( opus_int16 ) ); 75885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org 76885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org /* LP and HP filter mid signal */ 77e3ea049fcaee2247e45f0ce793d4313babb4ef69tlegrand@chromium.org ALLOC( LP_mid, frame_length, opus_int16 ); 78e3ea049fcaee2247e45f0ce793d4313babb4ef69tlegrand@chromium.org ALLOC( HP_mid, frame_length, opus_int16 ); 79885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org for( n = 0; n < frame_length; n++ ) { 80885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org sum = silk_RSHIFT_ROUND( silk_ADD_LSHIFT( mid[ n ] + mid[ n + 2 ], mid[ n + 1 ], 1 ), 2 ); 81885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org LP_mid[ n ] = sum; 82885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org HP_mid[ n ] = mid[ n + 1 ] - sum; 83885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org } 84885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org 85885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org /* LP and HP filter side signal */ 86e3ea049fcaee2247e45f0ce793d4313babb4ef69tlegrand@chromium.org ALLOC( LP_side, frame_length, opus_int16 ); 87e3ea049fcaee2247e45f0ce793d4313babb4ef69tlegrand@chromium.org ALLOC( HP_side, frame_length, opus_int16 ); 88885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org for( n = 0; n < frame_length; n++ ) { 89885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org sum = silk_RSHIFT_ROUND( silk_ADD_LSHIFT( side[ n ] + side[ n + 2 ], side[ n + 1 ], 1 ), 2 ); 90885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org LP_side[ n ] = sum; 91885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org HP_side[ n ] = side[ n + 1 ] - sum; 92885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org } 93885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org 94885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org /* Find energies and predictors */ 95885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org is10msFrame = frame_length == 10 * fs_kHz; 96885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org smooth_coef_Q16 = is10msFrame ? 97885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org SILK_FIX_CONST( STEREO_RATIO_SMOOTH_COEF / 2, 16 ) : 98885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org SILK_FIX_CONST( STEREO_RATIO_SMOOTH_COEF, 16 ); 99885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org smooth_coef_Q16 = silk_SMULWB( silk_SMULBB( prev_speech_act_Q8, prev_speech_act_Q8 ), smooth_coef_Q16 ); 100885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org 101885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org pred_Q13[ 0 ] = silk_stereo_find_predictor( &LP_ratio_Q14, LP_mid, LP_side, &state->mid_side_amp_Q0[ 0 ], frame_length, smooth_coef_Q16 ); 102885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org pred_Q13[ 1 ] = silk_stereo_find_predictor( &HP_ratio_Q14, HP_mid, HP_side, &state->mid_side_amp_Q0[ 2 ], frame_length, smooth_coef_Q16 ); 103885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org /* Ratio of the norms of residual and mid signals */ 104885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org frac_Q16 = silk_SMLABB( HP_ratio_Q14, LP_ratio_Q14, 3 ); 105885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org frac_Q16 = silk_min( frac_Q16, SILK_FIX_CONST( 1, 16 ) ); 106885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org 107885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org /* Determine bitrate distribution between mid and side, and possibly reduce stereo width */ 108885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org total_rate_bps -= is10msFrame ? 1200 : 600; /* Subtract approximate bitrate for coding stereo parameters */ 109885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org if( total_rate_bps < 1 ) { 110885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org total_rate_bps = 1; 111885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org } 112885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org min_mid_rate_bps = silk_SMLABB( 2000, fs_kHz, 900 ); 113885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org silk_assert( min_mid_rate_bps < 32767 ); 114885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org /* Default bitrate distribution: 8 parts for Mid and (5+3*frac) parts for Side. so: mid_rate = ( 8 / ( 13 + 3 * frac ) ) * total_ rate */ 115885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org frac_3_Q16 = silk_MUL( 3, frac_Q16 ); 116885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org mid_side_rates_bps[ 0 ] = silk_DIV32_varQ( total_rate_bps, SILK_FIX_CONST( 8 + 5, 16 ) + frac_3_Q16, 16+3 ); 117885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org /* If Mid bitrate below minimum, reduce stereo width */ 118885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org if( mid_side_rates_bps[ 0 ] < min_mid_rate_bps ) { 119885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org mid_side_rates_bps[ 0 ] = min_mid_rate_bps; 120885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org mid_side_rates_bps[ 1 ] = total_rate_bps - mid_side_rates_bps[ 0 ]; 121885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org /* width = 4 * ( 2 * side_rate - min_rate ) / ( ( 1 + 3 * frac ) * min_rate ) */ 122885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org width_Q14 = silk_DIV32_varQ( silk_LSHIFT( mid_side_rates_bps[ 1 ], 1 ) - min_mid_rate_bps, 123885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org silk_SMULWB( SILK_FIX_CONST( 1, 16 ) + frac_3_Q16, min_mid_rate_bps ), 14+2 ); 124885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org width_Q14 = silk_LIMIT( width_Q14, 0, SILK_FIX_CONST( 1, 14 ) ); 125885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org } else { 126885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org mid_side_rates_bps[ 1 ] = total_rate_bps - mid_side_rates_bps[ 0 ]; 127885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org width_Q14 = SILK_FIX_CONST( 1, 14 ); 128885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org } 129885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org 130885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org /* Smoother */ 131885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org state->smth_width_Q14 = (opus_int16)silk_SMLAWB( state->smth_width_Q14, width_Q14 - state->smth_width_Q14, smooth_coef_Q16 ); 132885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org 133885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org /* At very low bitrates or for inputs that are nearly amplitude panned, switch to panned-mono coding */ 134885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org *mid_only_flag = 0; 135885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org if( toMono ) { 136885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org /* Last frame before stereo->mono transition; collapse stereo width */ 137885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org width_Q14 = 0; 138885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org pred_Q13[ 0 ] = 0; 139885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org pred_Q13[ 1 ] = 0; 140885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org silk_stereo_quant_pred( pred_Q13, ix ); 141885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org } else if( state->width_prev_Q14 == 0 && 142885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org ( 8 * total_rate_bps < 13 * min_mid_rate_bps || silk_SMULWB( frac_Q16, state->smth_width_Q14 ) < SILK_FIX_CONST( 0.05, 14 ) ) ) 143885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org { 144885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org /* Code as panned-mono; previous frame already had zero width */ 145885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org /* Scale down and quantize predictors */ 146885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org pred_Q13[ 0 ] = silk_RSHIFT( silk_SMULBB( state->smth_width_Q14, pred_Q13[ 0 ] ), 14 ); 147885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org pred_Q13[ 1 ] = silk_RSHIFT( silk_SMULBB( state->smth_width_Q14, pred_Q13[ 1 ] ), 14 ); 148885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org silk_stereo_quant_pred( pred_Q13, ix ); 149885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org /* Collapse stereo width */ 150885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org width_Q14 = 0; 151885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org pred_Q13[ 0 ] = 0; 152885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org pred_Q13[ 1 ] = 0; 153885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org mid_side_rates_bps[ 0 ] = total_rate_bps; 154885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org mid_side_rates_bps[ 1 ] = 0; 155885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org *mid_only_flag = 1; 156885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org } else if( state->width_prev_Q14 != 0 && 157885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org ( 8 * total_rate_bps < 11 * min_mid_rate_bps || silk_SMULWB( frac_Q16, state->smth_width_Q14 ) < SILK_FIX_CONST( 0.02, 14 ) ) ) 158885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org { 159885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org /* Transition to zero-width stereo */ 160885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org /* Scale down and quantize predictors */ 161885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org pred_Q13[ 0 ] = silk_RSHIFT( silk_SMULBB( state->smth_width_Q14, pred_Q13[ 0 ] ), 14 ); 162885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org pred_Q13[ 1 ] = silk_RSHIFT( silk_SMULBB( state->smth_width_Q14, pred_Q13[ 1 ] ), 14 ); 163885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org silk_stereo_quant_pred( pred_Q13, ix ); 164885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org /* Collapse stereo width */ 165885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org width_Q14 = 0; 166885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org pred_Q13[ 0 ] = 0; 167885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org pred_Q13[ 1 ] = 0; 168885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org } else if( state->smth_width_Q14 > SILK_FIX_CONST( 0.95, 14 ) ) { 169885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org /* Full-width stereo coding */ 170885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org silk_stereo_quant_pred( pred_Q13, ix ); 171885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org width_Q14 = SILK_FIX_CONST( 1, 14 ); 172885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org } else { 173885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org /* Reduced-width stereo coding; scale down and quantize predictors */ 174885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org pred_Q13[ 0 ] = silk_RSHIFT( silk_SMULBB( state->smth_width_Q14, pred_Q13[ 0 ] ), 14 ); 175885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org pred_Q13[ 1 ] = silk_RSHIFT( silk_SMULBB( state->smth_width_Q14, pred_Q13[ 1 ] ), 14 ); 176885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org silk_stereo_quant_pred( pred_Q13, ix ); 177885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org width_Q14 = state->smth_width_Q14; 178885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org } 179885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org 180885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org /* Make sure to keep on encoding until the tapered output has been transmitted */ 181885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org if( *mid_only_flag == 1 ) { 182885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org state->silent_side_len += frame_length - STEREO_INTERP_LEN_MS * fs_kHz; 183885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org if( state->silent_side_len < LA_SHAPE_MS * fs_kHz ) { 184885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org *mid_only_flag = 0; 185885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org } else { 186885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org /* Limit to avoid wrapping around */ 187885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org state->silent_side_len = 10000; 188885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org } 189885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org } else { 190885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org state->silent_side_len = 0; 191885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org } 192885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org 193885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org if( *mid_only_flag == 0 && mid_side_rates_bps[ 1 ] < 1 ) { 194885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org mid_side_rates_bps[ 1 ] = 1; 195885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org mid_side_rates_bps[ 0 ] = silk_max_int( 1, total_rate_bps - mid_side_rates_bps[ 1 ]); 196885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org } 197885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org 198885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org /* Interpolate predictors and subtract prediction from side channel */ 199885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org pred0_Q13 = -state->pred_prev_Q13[ 0 ]; 200885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org pred1_Q13 = -state->pred_prev_Q13[ 1 ]; 201885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org w_Q24 = silk_LSHIFT( state->width_prev_Q14, 10 ); 202885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org denom_Q16 = silk_DIV32_16( (opus_int32)1 << 16, STEREO_INTERP_LEN_MS * fs_kHz ); 203885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org delta0_Q13 = -silk_RSHIFT_ROUND( silk_SMULBB( pred_Q13[ 0 ] - state->pred_prev_Q13[ 0 ], denom_Q16 ), 16 ); 204885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org delta1_Q13 = -silk_RSHIFT_ROUND( silk_SMULBB( pred_Q13[ 1 ] - state->pred_prev_Q13[ 1 ], denom_Q16 ), 16 ); 205885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org deltaw_Q24 = silk_LSHIFT( silk_SMULWB( width_Q14 - state->width_prev_Q14, denom_Q16 ), 10 ); 206885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org for( n = 0; n < STEREO_INTERP_LEN_MS * fs_kHz; n++ ) { 207885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org pred0_Q13 += delta0_Q13; 208885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org pred1_Q13 += delta1_Q13; 209885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org w_Q24 += deltaw_Q24; 210885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org sum = silk_LSHIFT( silk_ADD_LSHIFT( mid[ n ] + mid[ n + 2 ], mid[ n + 1 ], 1 ), 9 ); /* Q11 */ 211885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org sum = silk_SMLAWB( silk_SMULWB( w_Q24, side[ n + 1 ] ), sum, pred0_Q13 ); /* Q8 */ 212885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org sum = silk_SMLAWB( sum, silk_LSHIFT( (opus_int32)mid[ n + 1 ], 11 ), pred1_Q13 ); /* Q8 */ 213885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org x2[ n - 1 ] = (opus_int16)silk_SAT16( silk_RSHIFT_ROUND( sum, 8 ) ); 214885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org } 215885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org 216885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org pred0_Q13 = -pred_Q13[ 0 ]; 217885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org pred1_Q13 = -pred_Q13[ 1 ]; 218885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org w_Q24 = silk_LSHIFT( width_Q14, 10 ); 219885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org for( n = STEREO_INTERP_LEN_MS * fs_kHz; n < frame_length; n++ ) { 220885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org sum = silk_LSHIFT( silk_ADD_LSHIFT( mid[ n ] + mid[ n + 2 ], mid[ n + 1 ], 1 ), 9 ); /* Q11 */ 221885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org sum = silk_SMLAWB( silk_SMULWB( w_Q24, side[ n + 1 ] ), sum, pred0_Q13 ); /* Q8 */ 222885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org sum = silk_SMLAWB( sum, silk_LSHIFT( (opus_int32)mid[ n + 1 ], 11 ), pred1_Q13 ); /* Q8 */ 223885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org x2[ n - 1 ] = (opus_int16)silk_SAT16( silk_RSHIFT_ROUND( sum, 8 ) ); 224885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org } 225885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org state->pred_prev_Q13[ 0 ] = (opus_int16)pred_Q13[ 0 ]; 226885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org state->pred_prev_Q13[ 1 ] = (opus_int16)pred_Q13[ 1 ]; 227885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org state->width_prev_Q14 = (opus_int16)width_Q14; 228e3ea049fcaee2247e45f0ce793d4313babb4ef69tlegrand@chromium.org RESTORE_STACK; 229885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org} 230