Gregory Maxwell | ae23114 | 2011-07-30 08:18:48 -0400 | [diff] [blame] | 1 | /*********************************************************************** |
| 2 | Copyright (c) 2006-2011, Skype Limited. All rights reserved. |
| 3 | Redistribution and use in source and binary forms, with or without |
Jean-Marc Valin | ae00e60 | 2012-04-20 16:31:04 -0400 | [diff] [blame] | 4 | modification, are permitted provided that the following conditions |
| 5 | are met: |
Gregory Maxwell | ae23114 | 2011-07-30 08:18:48 -0400 | [diff] [blame] | 6 | - Redistributions of source code must retain the above copyright notice, |
| 7 | this list of conditions and the following disclaimer. |
| 8 | - Redistributions in binary form must reproduce the above copyright |
| 9 | notice, this list of conditions and the following disclaimer in the |
| 10 | documentation and/or other materials provided with the distribution. |
Jean-Marc Valin | ae00e60 | 2012-04-20 16:31:04 -0400 | [diff] [blame] | 11 | - Neither the name of Internet Society, IETF or IETF Trust, nor the |
| 12 | names of specific contributors, may be used to endorse or promote |
| 13 | products derived from this software without specific prior written |
| 14 | permission. |
| 15 | THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS “AS IS” |
| 16 | AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| 17 | IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| 18 | ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE |
| 19 | LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR |
| 20 | CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF |
| 21 | SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
| 22 | INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN |
| 23 | CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
| 24 | ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE |
| 25 | POSSIBILITY OF SUCH DAMAGE. |
Gregory Maxwell | ae23114 | 2011-07-30 08:18:48 -0400 | [diff] [blame] | 26 | ***********************************************************************/ |
| 27 | |
Jean-Marc Valin | 5a48412 | 2011-08-15 10:49:53 -0400 | [diff] [blame] | 28 | #ifdef HAVE_CONFIG_H |
| 29 | #include "config.h" |
| 30 | #endif |
| 31 | |
Jean-Marc Valin | 1c2f563 | 2011-09-16 01:16:53 -0700 | [diff] [blame] | 32 | #include "main.h" |
Gregory Maxwell | ae23114 | 2011-07-30 08:18:48 -0400 | [diff] [blame] | 33 | |
| 34 | /* Convert Left/Right stereo signal to adaptive Mid/Side representation */ |
| 35 | void silk_stereo_LR_to_MS( |
Koen Vos | acc7a6c | 2011-10-28 19:44:26 -0400 | [diff] [blame] | 36 | stereo_enc_state *state, /* I/O State */ |
| 37 | opus_int16 x1[], /* I/O Left input signal, becomes mid signal */ |
| 38 | opus_int16 x2[], /* I/O Right input signal, becomes side signal */ |
| 39 | opus_int8 ix[ 2 ][ 3 ], /* O Quantization indices */ |
| 40 | opus_int8 *mid_only_flag, /* O Flag: only mid signal coded */ |
| 41 | opus_int32 mid_side_rates_bps[], /* O Bitrates for mid and side signals */ |
| 42 | opus_int32 total_rate_bps, /* I Total bitrate */ |
| 43 | opus_int prev_speech_act_Q8, /* I Speech activity level in previous frame */ |
| 44 | opus_int toMono, /* I Last frame before a stereo->mono transition */ |
| 45 | opus_int fs_kHz, /* I Sample rate (kHz) */ |
| 46 | opus_int frame_length /* I Number of samples */ |
Gregory Maxwell | ae23114 | 2011-07-30 08:18:48 -0400 | [diff] [blame] | 47 | ) |
| 48 | { |
| 49 | opus_int n, is10msFrame, denom_Q16, delta0_Q13, delta1_Q13; |
| 50 | opus_int32 sum, diff, smooth_coef_Q16, pred_Q13[ 2 ], pred0_Q13, pred1_Q13; |
| 51 | opus_int32 LP_ratio_Q14, HP_ratio_Q14, frac_Q16, frac_3_Q16, min_mid_rate_bps, width_Q14, w_Q24, deltaw_Q24; |
| 52 | opus_int16 side[ MAX_FRAME_LENGTH + 2 ]; |
| 53 | opus_int16 LP_mid[ MAX_FRAME_LENGTH ], HP_mid[ MAX_FRAME_LENGTH ]; |
| 54 | opus_int16 LP_side[ MAX_FRAME_LENGTH ], HP_side[ MAX_FRAME_LENGTH ]; |
| 55 | opus_int16 *mid = &x1[ -2 ]; |
| 56 | |
| 57 | /* Convert to basic mid/side signals */ |
| 58 | for( n = 0; n < frame_length + 2; n++ ) { |
| 59 | sum = x1[ n - 2 ] + (opus_int32)x2[ n - 2 ]; |
| 60 | diff = x1[ n - 2 ] - (opus_int32)x2[ n - 2 ]; |
Jean-Marc Valin | fb3a437 | 2011-09-16 00:58:26 -0700 | [diff] [blame] | 61 | mid[ n ] = (opus_int16)silk_RSHIFT_ROUND( sum, 1 ); |
| 62 | side[ n ] = (opus_int16)silk_SAT16( silk_RSHIFT_ROUND( diff, 1 ) ); |
Gregory Maxwell | ae23114 | 2011-07-30 08:18:48 -0400 | [diff] [blame] | 63 | } |
| 64 | |
| 65 | /* Buffering */ |
Jean-Marc Valin | fb3a437 | 2011-09-16 00:58:26 -0700 | [diff] [blame] | 66 | silk_memcpy( mid, state->sMid, 2 * sizeof( opus_int16 ) ); |
| 67 | silk_memcpy( side, state->sSide, 2 * sizeof( opus_int16 ) ); |
| 68 | silk_memcpy( state->sMid, &mid[ frame_length ], 2 * sizeof( opus_int16 ) ); |
| 69 | silk_memcpy( state->sSide, &side[ frame_length ], 2 * sizeof( opus_int16 ) ); |
Gregory Maxwell | ae23114 | 2011-07-30 08:18:48 -0400 | [diff] [blame] | 70 | |
| 71 | /* LP and HP filter mid signal */ |
| 72 | for( n = 0; n < frame_length; n++ ) { |
Jean-Marc Valin | fb3a437 | 2011-09-16 00:58:26 -0700 | [diff] [blame] | 73 | sum = silk_RSHIFT_ROUND( silk_ADD_LSHIFT( mid[ n ] + mid[ n + 2 ], mid[ n + 1 ], 1 ), 2 ); |
Gregory Maxwell | ae23114 | 2011-07-30 08:18:48 -0400 | [diff] [blame] | 74 | LP_mid[ n ] = sum; |
| 75 | HP_mid[ n ] = mid[ n + 1 ] - sum; |
| 76 | } |
| 77 | |
| 78 | /* LP and HP filter side signal */ |
| 79 | for( n = 0; n < frame_length; n++ ) { |
Jean-Marc Valin | fb3a437 | 2011-09-16 00:58:26 -0700 | [diff] [blame] | 80 | sum = silk_RSHIFT_ROUND( silk_ADD_LSHIFT( side[ n ] + side[ n + 2 ], side[ n + 1 ], 1 ), 2 ); |
Gregory Maxwell | ae23114 | 2011-07-30 08:18:48 -0400 | [diff] [blame] | 81 | LP_side[ n ] = sum; |
| 82 | HP_side[ n ] = side[ n + 1 ] - sum; |
| 83 | } |
| 84 | |
| 85 | /* Find energies and predictors */ |
| 86 | is10msFrame = frame_length == 10 * fs_kHz; |
| 87 | smooth_coef_Q16 = is10msFrame ? |
| 88 | SILK_FIX_CONST( STEREO_RATIO_SMOOTH_COEF / 2, 16 ) : |
| 89 | SILK_FIX_CONST( STEREO_RATIO_SMOOTH_COEF, 16 ); |
Jean-Marc Valin | b24e574 | 2011-10-11 21:09:14 -0400 | [diff] [blame] | 90 | smooth_coef_Q16 = silk_SMULWB( silk_SMULBB( prev_speech_act_Q8, prev_speech_act_Q8 ), smooth_coef_Q16 ); |
Gregory Maxwell | ae23114 | 2011-07-30 08:18:48 -0400 | [diff] [blame] | 91 | |
| 92 | 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 ); |
| 93 | 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 ); |
| 94 | /* Ratio of the norms of residual and mid signals */ |
Jean-Marc Valin | fb3a437 | 2011-09-16 00:58:26 -0700 | [diff] [blame] | 95 | frac_Q16 = silk_SMLABB( HP_ratio_Q14, LP_ratio_Q14, 3 ); |
| 96 | frac_Q16 = silk_min( frac_Q16, SILK_FIX_CONST( 1, 16 ) ); |
Gregory Maxwell | ae23114 | 2011-07-30 08:18:48 -0400 | [diff] [blame] | 97 | |
| 98 | /* Determine bitrate distribution between mid and side, and possibly reduce stereo width */ |
| 99 | total_rate_bps -= is10msFrame ? 1200 : 600; /* Subtract approximate bitrate for coding stereo parameters */ |
Koen Vos | 8887566 | 2011-10-06 13:38:26 -0400 | [diff] [blame] | 100 | if( total_rate_bps < 1 ) { |
Jean-Marc Valin | d76bc91 | 2011-09-07 01:37:58 -0400 | [diff] [blame] | 101 | total_rate_bps = 1; |
Koen Vos | 480ba70 | 2011-10-05 13:49:54 -0400 | [diff] [blame] | 102 | } |
Jean-Marc Valin | fb3a437 | 2011-09-16 00:58:26 -0700 | [diff] [blame] | 103 | min_mid_rate_bps = silk_SMLABB( 2000, fs_kHz, 900 ); |
| 104 | silk_assert( min_mid_rate_bps < 32767 ); |
Gregory Maxwell | ae23114 | 2011-07-30 08:18:48 -0400 | [diff] [blame] | 105 | /* Default bitrate distribution: 8 parts for Mid and (5+3*frac) parts for Side. so: mid_rate = ( 8 / ( 13 + 3 * frac ) ) * total_ rate */ |
Jean-Marc Valin | fb3a437 | 2011-09-16 00:58:26 -0700 | [diff] [blame] | 106 | frac_3_Q16 = silk_MUL( 3, frac_Q16 ); |
Gregory Maxwell | ae23114 | 2011-07-30 08:18:48 -0400 | [diff] [blame] | 107 | mid_side_rates_bps[ 0 ] = silk_DIV32_varQ( total_rate_bps, SILK_FIX_CONST( 8 + 5, 16 ) + frac_3_Q16, 16+3 ); |
| 108 | /* If Mid bitrate below minimum, reduce stereo width */ |
| 109 | if( mid_side_rates_bps[ 0 ] < min_mid_rate_bps ) { |
| 110 | mid_side_rates_bps[ 0 ] = min_mid_rate_bps; |
| 111 | mid_side_rates_bps[ 1 ] = total_rate_bps - mid_side_rates_bps[ 0 ]; |
| 112 | /* width = 4 * ( 2 * side_rate - min_rate ) / ( ( 1 + 3 * frac ) * min_rate ) */ |
Jean-Marc Valin | fb3a437 | 2011-09-16 00:58:26 -0700 | [diff] [blame] | 113 | width_Q14 = silk_DIV32_varQ( silk_LSHIFT( mid_side_rates_bps[ 1 ], 1 ) - min_mid_rate_bps, |
| 114 | silk_SMULWB( SILK_FIX_CONST( 1, 16 ) + frac_3_Q16, min_mid_rate_bps ), 14+2 ); |
| 115 | width_Q14 = silk_LIMIT( width_Q14, 0, SILK_FIX_CONST( 1, 14 ) ); |
Gregory Maxwell | ae23114 | 2011-07-30 08:18:48 -0400 | [diff] [blame] | 116 | } else { |
| 117 | mid_side_rates_bps[ 1 ] = total_rate_bps - mid_side_rates_bps[ 0 ]; |
| 118 | width_Q14 = SILK_FIX_CONST( 1, 14 ); |
| 119 | } |
| 120 | |
| 121 | /* Smoother */ |
Jean-Marc Valin | fb3a437 | 2011-09-16 00:58:26 -0700 | [diff] [blame] | 122 | state->smth_width_Q14 = (opus_int16)silk_SMLAWB( state->smth_width_Q14, width_Q14 - state->smth_width_Q14, smooth_coef_Q16 ); |
Gregory Maxwell | ae23114 | 2011-07-30 08:18:48 -0400 | [diff] [blame] | 123 | |
Koen Vos | 480ba70 | 2011-10-05 13:49:54 -0400 | [diff] [blame] | 124 | /* At very low bitrates or for inputs that are nearly amplitude panned, switch to panned-mono coding */ |
Koen Vos | 4e1ce38 | 2011-08-25 13:50:21 -0400 | [diff] [blame] | 125 | *mid_only_flag = 0; |
Koen Vos | 8887566 | 2011-10-06 13:38:26 -0400 | [diff] [blame] | 126 | if( toMono ) { |
| 127 | /* Last frame before stereo->mono transition; collapse stereo width */ |
| 128 | width_Q14 = 0; |
| 129 | pred_Q13[ 0 ] = 0; |
| 130 | pred_Q13[ 1 ] = 0; |
| 131 | silk_stereo_quant_pred( pred_Q13, ix ); |
| 132 | } else if( state->width_prev_Q14 == 0 && |
Jean-Marc Valin | fb3a437 | 2011-09-16 00:58:26 -0700 | [diff] [blame] | 133 | ( 8 * total_rate_bps < 13 * min_mid_rate_bps || silk_SMULWB( frac_Q16, state->smth_width_Q14 ) < SILK_FIX_CONST( 0.05, 14 ) ) ) |
Gregory Maxwell | ae23114 | 2011-07-30 08:18:48 -0400 | [diff] [blame] | 134 | { |
Koen Vos | 480ba70 | 2011-10-05 13:49:54 -0400 | [diff] [blame] | 135 | /* Code as panned-mono; previous frame already had zero width */ |
| 136 | /* Scale down and quantize predictors */ |
| 137 | pred_Q13[ 0 ] = silk_RSHIFT( silk_SMULBB( state->smth_width_Q14, pred_Q13[ 0 ] ), 14 ); |
| 138 | pred_Q13[ 1 ] = silk_RSHIFT( silk_SMULBB( state->smth_width_Q14, pred_Q13[ 1 ] ), 14 ); |
| 139 | silk_stereo_quant_pred( pred_Q13, ix ); |
| 140 | /* Collapse stereo width */ |
Gregory Maxwell | ae23114 | 2011-07-30 08:18:48 -0400 | [diff] [blame] | 141 | width_Q14 = 0; |
Koen Vos | 480ba70 | 2011-10-05 13:49:54 -0400 | [diff] [blame] | 142 | pred_Q13[ 0 ] = 0; |
| 143 | pred_Q13[ 1 ] = 0; |
Gregory Maxwell | ae23114 | 2011-07-30 08:18:48 -0400 | [diff] [blame] | 144 | mid_side_rates_bps[ 0 ] = total_rate_bps; |
| 145 | mid_side_rates_bps[ 1 ] = 0; |
Koen Vos | 4e1ce38 | 2011-08-25 13:50:21 -0400 | [diff] [blame] | 146 | *mid_only_flag = 1; |
Gregory Maxwell | ae23114 | 2011-07-30 08:18:48 -0400 | [diff] [blame] | 147 | } else if( state->width_prev_Q14 != 0 && |
Jean-Marc Valin | fb3a437 | 2011-09-16 00:58:26 -0700 | [diff] [blame] | 148 | ( 8 * total_rate_bps < 11 * min_mid_rate_bps || silk_SMULWB( frac_Q16, state->smth_width_Q14 ) < SILK_FIX_CONST( 0.02, 14 ) ) ) |
Gregory Maxwell | ae23114 | 2011-07-30 08:18:48 -0400 | [diff] [blame] | 149 | { |
Koen Vos | 480ba70 | 2011-10-05 13:49:54 -0400 | [diff] [blame] | 150 | /* Transition to zero-width stereo */ |
| 151 | /* Scale down and quantize predictors */ |
| 152 | pred_Q13[ 0 ] = silk_RSHIFT( silk_SMULBB( state->smth_width_Q14, pred_Q13[ 0 ] ), 14 ); |
| 153 | pred_Q13[ 1 ] = silk_RSHIFT( silk_SMULBB( state->smth_width_Q14, pred_Q13[ 1 ] ), 14 ); |
| 154 | silk_stereo_quant_pred( pred_Q13, ix ); |
| 155 | /* Collapse stereo width */ |
Gregory Maxwell | ae23114 | 2011-07-30 08:18:48 -0400 | [diff] [blame] | 156 | width_Q14 = 0; |
Koen Vos | 480ba70 | 2011-10-05 13:49:54 -0400 | [diff] [blame] | 157 | pred_Q13[ 0 ] = 0; |
| 158 | pred_Q13[ 1 ] = 0; |
Gregory Maxwell | ae23114 | 2011-07-30 08:18:48 -0400 | [diff] [blame] | 159 | } else if( state->smth_width_Q14 > SILK_FIX_CONST( 0.95, 14 ) ) { |
Koen Vos | 480ba70 | 2011-10-05 13:49:54 -0400 | [diff] [blame] | 160 | /* Full-width stereo coding */ |
| 161 | silk_stereo_quant_pred( pred_Q13, ix ); |
Gregory Maxwell | ae23114 | 2011-07-30 08:18:48 -0400 | [diff] [blame] | 162 | width_Q14 = SILK_FIX_CONST( 1, 14 ); |
| 163 | } else { |
Koen Vos | 480ba70 | 2011-10-05 13:49:54 -0400 | [diff] [blame] | 164 | /* Reduced-width stereo coding; scale down and quantize predictors */ |
| 165 | pred_Q13[ 0 ] = silk_RSHIFT( silk_SMULBB( state->smth_width_Q14, pred_Q13[ 0 ] ), 14 ); |
| 166 | pred_Q13[ 1 ] = silk_RSHIFT( silk_SMULBB( state->smth_width_Q14, pred_Q13[ 1 ] ), 14 ); |
| 167 | silk_stereo_quant_pred( pred_Q13, ix ); |
Gregory Maxwell | ae23114 | 2011-07-30 08:18:48 -0400 | [diff] [blame] | 168 | width_Q14 = state->smth_width_Q14; |
| 169 | } |
| 170 | |
Jean-Marc Valin | b24e574 | 2011-10-11 21:09:14 -0400 | [diff] [blame] | 171 | /* Make sure to keep on encoding until the tapered output has been transmitted */ |
| 172 | if( *mid_only_flag == 1 ) { |
| 173 | state->silent_side_len += frame_length - STEREO_INTERP_LEN_MS * fs_kHz; |
| 174 | if( state->silent_side_len < LA_SHAPE_MS * fs_kHz ) { |
| 175 | *mid_only_flag = 0; |
| 176 | } else { |
| 177 | /* Limit to avoid wrapping around */ |
| 178 | state->silent_side_len = 10000; |
| 179 | } |
| 180 | } else { |
| 181 | state->silent_side_len = 0; |
| 182 | } |
| 183 | |
| 184 | if( *mid_only_flag == 0 && mid_side_rates_bps[ 1 ] < 1 ) { |
Jean-Marc Valin | 6e5f6d0 | 2011-10-07 18:08:41 -0400 | [diff] [blame] | 185 | mid_side_rates_bps[ 1 ] = 1; |
| 186 | mid_side_rates_bps[ 0 ] = silk_max_int( 1, total_rate_bps - mid_side_rates_bps[ 1 ]); |
| 187 | } |
Gregory Maxwell | ae23114 | 2011-07-30 08:18:48 -0400 | [diff] [blame] | 188 | |
Gregory Maxwell | ae23114 | 2011-07-30 08:18:48 -0400 | [diff] [blame] | 189 | /* Interpolate predictors and subtract prediction from side channel */ |
| 190 | pred0_Q13 = -state->pred_prev_Q13[ 0 ]; |
| 191 | pred1_Q13 = -state->pred_prev_Q13[ 1 ]; |
Jean-Marc Valin | fb3a437 | 2011-09-16 00:58:26 -0700 | [diff] [blame] | 192 | w_Q24 = silk_LSHIFT( state->width_prev_Q14, 10 ); |
Jean-Marc Valin | 905197d | 2012-03-08 14:09:09 -0500 | [diff] [blame] | 193 | denom_Q16 = silk_DIV32_16( (opus_int32)1 << 16, STEREO_INTERP_LEN_MS * fs_kHz ); |
Jean-Marc Valin | fb3a437 | 2011-09-16 00:58:26 -0700 | [diff] [blame] | 194 | delta0_Q13 = -silk_RSHIFT_ROUND( silk_SMULBB( pred_Q13[ 0 ] - state->pred_prev_Q13[ 0 ], denom_Q16 ), 16 ); |
| 195 | delta1_Q13 = -silk_RSHIFT_ROUND( silk_SMULBB( pred_Q13[ 1 ] - state->pred_prev_Q13[ 1 ], denom_Q16 ), 16 ); |
| 196 | deltaw_Q24 = silk_LSHIFT( silk_SMULWB( width_Q14 - state->width_prev_Q14, denom_Q16 ), 10 ); |
Gregory Maxwell | ae23114 | 2011-07-30 08:18:48 -0400 | [diff] [blame] | 197 | for( n = 0; n < STEREO_INTERP_LEN_MS * fs_kHz; n++ ) { |
| 198 | pred0_Q13 += delta0_Q13; |
| 199 | pred1_Q13 += delta1_Q13; |
| 200 | w_Q24 += deltaw_Q24; |
Koen Vos | bf75c8e | 2011-12-13 14:47:31 -0500 | [diff] [blame] | 201 | sum = silk_LSHIFT( silk_ADD_LSHIFT( mid[ n ] + mid[ n + 2 ], mid[ n + 1 ], 1 ), 9 ); /* Q11 */ |
| 202 | sum = silk_SMLAWB( silk_SMULWB( w_Q24, side[ n + 1 ] ), sum, pred0_Q13 ); /* Q8 */ |
| 203 | sum = silk_SMLAWB( sum, silk_LSHIFT( (opus_int32)mid[ n + 1 ], 11 ), pred1_Q13 ); /* Q8 */ |
Jean-Marc Valin | fb3a437 | 2011-09-16 00:58:26 -0700 | [diff] [blame] | 204 | x2[ n - 1 ] = (opus_int16)silk_SAT16( silk_RSHIFT_ROUND( sum, 8 ) ); |
Gregory Maxwell | ae23114 | 2011-07-30 08:18:48 -0400 | [diff] [blame] | 205 | } |
Koen Vos | 480ba70 | 2011-10-05 13:49:54 -0400 | [diff] [blame] | 206 | |
Gregory Maxwell | ae23114 | 2011-07-30 08:18:48 -0400 | [diff] [blame] | 207 | pred0_Q13 = -pred_Q13[ 0 ]; |
| 208 | pred1_Q13 = -pred_Q13[ 1 ]; |
Jean-Marc Valin | fb3a437 | 2011-09-16 00:58:26 -0700 | [diff] [blame] | 209 | w_Q24 = silk_LSHIFT( width_Q14, 10 ); |
Gregory Maxwell | ae23114 | 2011-07-30 08:18:48 -0400 | [diff] [blame] | 210 | for( n = STEREO_INTERP_LEN_MS * fs_kHz; n < frame_length; n++ ) { |
Koen Vos | bf75c8e | 2011-12-13 14:47:31 -0500 | [diff] [blame] | 211 | sum = silk_LSHIFT( silk_ADD_LSHIFT( mid[ n ] + mid[ n + 2 ], mid[ n + 1 ], 1 ), 9 ); /* Q11 */ |
| 212 | sum = silk_SMLAWB( silk_SMULWB( w_Q24, side[ n + 1 ] ), sum, pred0_Q13 ); /* Q8 */ |
| 213 | sum = silk_SMLAWB( sum, silk_LSHIFT( (opus_int32)mid[ n + 1 ], 11 ), pred1_Q13 ); /* Q8 */ |
Jean-Marc Valin | fb3a437 | 2011-09-16 00:58:26 -0700 | [diff] [blame] | 214 | x2[ n - 1 ] = (opus_int16)silk_SAT16( silk_RSHIFT_ROUND( sum, 8 ) ); |
Gregory Maxwell | ae23114 | 2011-07-30 08:18:48 -0400 | [diff] [blame] | 215 | } |
| 216 | state->pred_prev_Q13[ 0 ] = (opus_int16)pred_Q13[ 0 ]; |
| 217 | state->pred_prev_Q13[ 1 ] = (opus_int16)pred_Q13[ 1 ]; |
| 218 | state->width_prev_Q14 = (opus_int16)width_Q14; |
| 219 | } |