86 lines
4.8 KiB
C
86 lines
4.8 KiB
C
/***********************************************************************
|
|
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"
|
|
|
|
/* Convert adaptive Mid/Side representation to Left/Right stereo signal */
|
|
void silk_stereo_MS_to_LR(
|
|
stereo_dec_state *state, /* I/O State */
|
|
opus_int16 x1[], /* I/O Left input signal, becomes mid signal */
|
|
opus_int16 x2[], /* I/O Right input signal, becomes side signal */
|
|
const opus_int32 pred_Q13[], /* I Predictors */
|
|
opus_int fs_kHz, /* I Samples rate (kHz) */
|
|
opus_int frame_length /* I Number of samples */
|
|
)
|
|
{
|
|
opus_int n, denom_Q16, delta0_Q13, delta1_Q13;
|
|
opus_int32 sum, diff, pred0_Q13, pred1_Q13;
|
|
|
|
/* Buffering */
|
|
silk_memcpy( x1, state->sMid, 2 * sizeof( opus_int16 ) );
|
|
silk_memcpy( x2, state->sSide, 2 * sizeof( opus_int16 ) );
|
|
silk_memcpy( state->sMid, &x1[ frame_length ], 2 * sizeof( opus_int16 ) );
|
|
silk_memcpy( state->sSide, &x2[ frame_length ], 2 * sizeof( opus_int16 ) );
|
|
|
|
/* Interpolate predictors and add prediction to side channel */
|
|
pred0_Q13 = state->pred_prev_Q13[ 0 ];
|
|
pred1_Q13 = state->pred_prev_Q13[ 1 ];
|
|
denom_Q16 = silk_DIV32_16( (opus_int32)1 << 16, STEREO_INTERP_LEN_MS * fs_kHz );
|
|
delta0_Q13 = silk_RSHIFT_ROUND( silk_SMULBB( pred_Q13[ 0 ] - state->pred_prev_Q13[ 0 ], denom_Q16 ), 16 );
|
|
delta1_Q13 = silk_RSHIFT_ROUND( silk_SMULBB( pred_Q13[ 1 ] - state->pred_prev_Q13[ 1 ], denom_Q16 ), 16 );
|
|
for( n = 0; n < STEREO_INTERP_LEN_MS * fs_kHz; n++ ) {
|
|
pred0_Q13 += delta0_Q13;
|
|
pred1_Q13 += delta1_Q13;
|
|
sum = silk_LSHIFT( silk_ADD_LSHIFT( x1[ n ] + x1[ n + 2 ], x1[ n + 1 ], 1 ), 9 ); /* Q11 */
|
|
sum = silk_SMLAWB( silk_LSHIFT( (opus_int32)x2[ n + 1 ], 8 ), sum, pred0_Q13 ); /* Q8 */
|
|
sum = silk_SMLAWB( sum, silk_LSHIFT( (opus_int32)x1[ n + 1 ], 11 ), pred1_Q13 ); /* Q8 */
|
|
x2[ n + 1 ] = (opus_int16)silk_SAT16( silk_RSHIFT_ROUND( sum, 8 ) );
|
|
}
|
|
pred0_Q13 = pred_Q13[ 0 ];
|
|
pred1_Q13 = pred_Q13[ 1 ];
|
|
for( n = STEREO_INTERP_LEN_MS * fs_kHz; n < frame_length; n++ ) {
|
|
sum = silk_LSHIFT( silk_ADD_LSHIFT( x1[ n ] + x1[ n + 2 ], x1[ n + 1 ], 1 ), 9 ); /* Q11 */
|
|
sum = silk_SMLAWB( silk_LSHIFT( (opus_int32)x2[ n + 1 ], 8 ), sum, pred0_Q13 ); /* Q8 */
|
|
sum = silk_SMLAWB( sum, silk_LSHIFT( (opus_int32)x1[ n + 1 ], 11 ), pred1_Q13 ); /* Q8 */
|
|
x2[ n + 1 ] = (opus_int16)silk_SAT16( silk_RSHIFT_ROUND( sum, 8 ) );
|
|
}
|
|
state->pred_prev_Q13[ 0 ] = pred_Q13[ 0 ];
|
|
state->pred_prev_Q13[ 1 ] = pred_Q13[ 1 ];
|
|
|
|
/* Convert to left/right signals */
|
|
for( n = 0; n < frame_length; n++ ) {
|
|
sum = x1[ n + 1 ] + (opus_int32)x2[ n + 1 ];
|
|
diff = x1[ n + 1 ] - (opus_int32)x2[ n + 1 ];
|
|
x1[ n + 1 ] = (opus_int16)silk_SAT16( sum );
|
|
x2[ n + 1 ] = (opus_int16)silk_SAT16( diff );
|
|
}
|
|
}
|