blob: 62521a4f352fcdd5513b4c53b72eaf8c6d842cce [file] [log] [blame]
Gregory Maxwellae231142011-07-30 08:18:48 -04001/***********************************************************************
2Copyright (c) 2006-2011, Skype Limited. All rights reserved.
3Redistribution and use in source and binary forms, with or without
Jean-Marc Valinae00e602012-04-20 16:31:04 -04004modification, are permitted provided that the following conditions
5are met:
Gregory Maxwellae231142011-07-30 08:18:48 -04006- Redistributions of source code must retain the above copyright notice,
7this list of conditions and the following disclaimer.
8- Redistributions in binary form must reproduce the above copyright
9notice, this list of conditions and the following disclaimer in the
10documentation and/or other materials provided with the distribution.
Ralph Gilesf2446c22013-09-16 14:40:04 -070011- Neither the name of Internet Society, IETF or IETF Trust, nor the
Jean-Marc Valinae00e602012-04-20 16:31:04 -040012names of specific contributors, may be used to endorse or promote
13products derived from this software without specific prior written
14permission.
Timothy B. Terriberry80ad3832013-05-19 18:00:39 -070015THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
Jean-Marc Valinae00e602012-04-20 16:31:04 -040016AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
19LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
20CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
21SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
22INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
23CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
24ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
25POSSIBILITY OF SUCH DAMAGE.
Gregory Maxwellae231142011-07-30 08:18:48 -040026***********************************************************************/
27
Jean-Marc Valin5a484122011-08-15 10:49:53 -040028#ifdef HAVE_CONFIG_H
29#include "config.h"
30#endif
31
Jean-Marc Valin1c2f5632011-09-16 01:16:53 -070032#include "main.h"
Gregory Maxwellae231142011-07-30 08:18:48 -040033
34/* Convert adaptive Mid/Side representation to Left/Right stereo signal */
35void silk_stereo_MS_to_LR(
Koen Vosacc7a6c2011-10-28 19:44:26 -040036 stereo_dec_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 const opus_int32 pred_Q13[], /* I Predictors */
40 opus_int fs_kHz, /* I Samples rate (kHz) */
41 opus_int frame_length /* I Number of samples */
Gregory Maxwellae231142011-07-30 08:18:48 -040042)
43{
44 opus_int n, denom_Q16, delta0_Q13, delta1_Q13;
45 opus_int32 sum, diff, pred0_Q13, pred1_Q13;
46
47 /* Buffering */
Jean-Marc Valinfb3a4372011-09-16 00:58:26 -070048 silk_memcpy( x1, state->sMid, 2 * sizeof( opus_int16 ) );
49 silk_memcpy( x2, state->sSide, 2 * sizeof( opus_int16 ) );
50 silk_memcpy( state->sMid, &x1[ frame_length ], 2 * sizeof( opus_int16 ) );
51 silk_memcpy( state->sSide, &x2[ frame_length ], 2 * sizeof( opus_int16 ) );
Gregory Maxwellae231142011-07-30 08:18:48 -040052
53 /* Interpolate predictors and add prediction to side channel */
54 pred0_Q13 = state->pred_prev_Q13[ 0 ];
55 pred1_Q13 = state->pred_prev_Q13[ 1 ];
Jean-Marc Valin905197d2012-03-08 14:09:09 -050056 denom_Q16 = silk_DIV32_16( (opus_int32)1 << 16, STEREO_INTERP_LEN_MS * fs_kHz );
Jean-Marc Valinfb3a4372011-09-16 00:58:26 -070057 delta0_Q13 = silk_RSHIFT_ROUND( silk_SMULBB( pred_Q13[ 0 ] - state->pred_prev_Q13[ 0 ], denom_Q16 ), 16 );
58 delta1_Q13 = silk_RSHIFT_ROUND( silk_SMULBB( pred_Q13[ 1 ] - state->pred_prev_Q13[ 1 ], denom_Q16 ), 16 );
Gregory Maxwellae231142011-07-30 08:18:48 -040059 for( n = 0; n < STEREO_INTERP_LEN_MS * fs_kHz; n++ ) {
60 pred0_Q13 += delta0_Q13;
61 pred1_Q13 += delta1_Q13;
Koen Vosbf75c8e2011-12-13 14:47:31 -050062 sum = silk_LSHIFT( silk_ADD_LSHIFT( x1[ n ] + x1[ n + 2 ], x1[ n + 1 ], 1 ), 9 ); /* Q11 */
63 sum = silk_SMLAWB( silk_LSHIFT( (opus_int32)x2[ n + 1 ], 8 ), sum, pred0_Q13 ); /* Q8 */
64 sum = silk_SMLAWB( sum, silk_LSHIFT( (opus_int32)x1[ n + 1 ], 11 ), pred1_Q13 ); /* Q8 */
Jean-Marc Valinfb3a4372011-09-16 00:58:26 -070065 x2[ n + 1 ] = (opus_int16)silk_SAT16( silk_RSHIFT_ROUND( sum, 8 ) );
Gregory Maxwellae231142011-07-30 08:18:48 -040066 }
67 pred0_Q13 = pred_Q13[ 0 ];
68 pred1_Q13 = pred_Q13[ 1 ];
69 for( n = STEREO_INTERP_LEN_MS * fs_kHz; n < frame_length; n++ ) {
Koen Vosbf75c8e2011-12-13 14:47:31 -050070 sum = silk_LSHIFT( silk_ADD_LSHIFT( x1[ n ] + x1[ n + 2 ], x1[ n + 1 ], 1 ), 9 ); /* Q11 */
71 sum = silk_SMLAWB( silk_LSHIFT( (opus_int32)x2[ n + 1 ], 8 ), sum, pred0_Q13 ); /* Q8 */
72 sum = silk_SMLAWB( sum, silk_LSHIFT( (opus_int32)x1[ n + 1 ], 11 ), pred1_Q13 ); /* Q8 */
Jean-Marc Valinfb3a4372011-09-16 00:58:26 -070073 x2[ n + 1 ] = (opus_int16)silk_SAT16( silk_RSHIFT_ROUND( sum, 8 ) );
Gregory Maxwellae231142011-07-30 08:18:48 -040074 }
75 state->pred_prev_Q13[ 0 ] = pred_Q13[ 0 ];
76 state->pred_prev_Q13[ 1 ] = pred_Q13[ 1 ];
77
78 /* Convert to left/right signals */
79 for( n = 0; n < frame_length; n++ ) {
80 sum = x1[ n + 1 ] + (opus_int32)x2[ n + 1 ];
81 diff = x1[ n + 1 ] - (opus_int32)x2[ n + 1 ];
Jean-Marc Valinfb3a4372011-09-16 00:58:26 -070082 x1[ n + 1 ] = (opus_int16)silk_SAT16( sum );
83 x2[ n + 1 ] = (opus_int16)silk_SAT16( diff );
Gregory Maxwellae231142011-07-30 08:18:48 -040084 }
85}