1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/media/libopus/silk/stereo_decode_pred.c Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,73 @@
1.4 +/***********************************************************************
1.5 +Copyright (c) 2006-2011, Skype Limited. All rights reserved.
1.6 +Redistribution and use in source and binary forms, with or without
1.7 +modification, are permitted provided that the following conditions
1.8 +are met:
1.9 +- Redistributions of source code must retain the above copyright notice,
1.10 +this list of conditions and the following disclaimer.
1.11 +- Redistributions in binary form must reproduce the above copyright
1.12 +notice, this list of conditions and the following disclaimer in the
1.13 +documentation and/or other materials provided with the distribution.
1.14 +- Neither the name of Internet Society, IETF or IETF Trust, nor the
1.15 +names of specific contributors, may be used to endorse or promote
1.16 +products derived from this software without specific prior written
1.17 +permission.
1.18 +THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
1.19 +AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
1.20 +IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
1.21 +ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
1.22 +LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
1.23 +CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
1.24 +SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
1.25 +INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
1.26 +CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
1.27 +ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
1.28 +POSSIBILITY OF SUCH DAMAGE.
1.29 +***********************************************************************/
1.30 +
1.31 +#ifdef HAVE_CONFIG_H
1.32 +#include "config.h"
1.33 +#endif
1.34 +
1.35 +#include "main.h"
1.36 +
1.37 +/* Decode mid/side predictors */
1.38 +void silk_stereo_decode_pred(
1.39 + ec_dec *psRangeDec, /* I/O Compressor data structure */
1.40 + opus_int32 pred_Q13[] /* O Predictors */
1.41 +)
1.42 +{
1.43 + opus_int n, ix[ 2 ][ 3 ];
1.44 + opus_int32 low_Q13, step_Q13;
1.45 +
1.46 + /* Entropy decoding */
1.47 + n = ec_dec_icdf( psRangeDec, silk_stereo_pred_joint_iCDF, 8 );
1.48 + ix[ 0 ][ 2 ] = silk_DIV32_16( n, 5 );
1.49 + ix[ 1 ][ 2 ] = n - 5 * ix[ 0 ][ 2 ];
1.50 + for( n = 0; n < 2; n++ ) {
1.51 + ix[ n ][ 0 ] = ec_dec_icdf( psRangeDec, silk_uniform3_iCDF, 8 );
1.52 + ix[ n ][ 1 ] = ec_dec_icdf( psRangeDec, silk_uniform5_iCDF, 8 );
1.53 + }
1.54 +
1.55 + /* Dequantize */
1.56 + for( n = 0; n < 2; n++ ) {
1.57 + ix[ n ][ 0 ] += 3 * ix[ n ][ 2 ];
1.58 + low_Q13 = silk_stereo_pred_quant_Q13[ ix[ n ][ 0 ] ];
1.59 + step_Q13 = silk_SMULWB( silk_stereo_pred_quant_Q13[ ix[ n ][ 0 ] + 1 ] - low_Q13,
1.60 + SILK_FIX_CONST( 0.5 / STEREO_QUANT_SUB_STEPS, 16 ) );
1.61 + pred_Q13[ n ] = silk_SMLABB( low_Q13, step_Q13, 2 * ix[ n ][ 1 ] + 1 );
1.62 + }
1.63 +
1.64 + /* Subtract second from first predictor (helps when actually applying these) */
1.65 + pred_Q13[ 0 ] -= pred_Q13[ 1 ];
1.66 +}
1.67 +
1.68 +/* Decode mid-only flag */
1.69 +void silk_stereo_decode_mid_only(
1.70 + ec_dec *psRangeDec, /* I/O Compressor data structure */
1.71 + opus_int *decode_only_mid /* O Flag that only mid channel has been coded */
1.72 +)
1.73 +{
1.74 + /* Decode flag that only mid channel is coded */
1.75 + *decode_only_mid = ec_dec_icdf( psRangeDec, silk_stereo_only_code_mid_iCDF, 8 );
1.76 +}
