Line data    Source code

       1             : /***********************************************************************
       2             : Copyright (c) 2006-2011, Skype Limited. All rights reserved.
       3             : Redistribution and use in source and binary forms, with or without
       4             : modification, are permitted provided that the following conditions
       5             : are met:
       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.
      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.
      26             : ***********************************************************************/
      27             : 
      28             : #ifdef HAVE_CONFIG_H
      29             : #include "config.h"
      30             : #endif
      31             : 
      32             : #include "main.h"
      33             : 
      34             : /* Decode mid/side predictors */
      35           0 : void silk_stereo_decode_pred(
      36             :     ec_dec                      *psRangeDec,                    /* I/O  Compressor data structure                   */
      37             :     opus_int32                  pred_Q13[]                      /* O    Predictors                                  */
      38             : )
      39             : {
      40             :     opus_int   n, ix[ 2 ][ 3 ];
      41             :     opus_int32 low_Q13, step_Q13;
      42             : 
      43             :     /* Entropy decoding */
      44           0 :     n = ec_dec_icdf( psRangeDec, silk_stereo_pred_joint_iCDF, 8 );
      45           0 :     ix[ 0 ][ 2 ] = silk_DIV32_16( n, 5 );
      46           0 :     ix[ 1 ][ 2 ] = n - 5 * ix[ 0 ][ 2 ];
      47           0 :     for( n = 0; n < 2; n++ ) {
      48           0 :         ix[ n ][ 0 ] = ec_dec_icdf( psRangeDec, silk_uniform3_iCDF, 8 );
      49           0 :         ix[ n ][ 1 ] = ec_dec_icdf( psRangeDec, silk_uniform5_iCDF, 8 );
      50             :     }
      51             : 
      52             :     /* Dequantize */
      53           0 :     for( n = 0; n < 2; n++ ) {
      54           0 :         ix[ n ][ 0 ] += 3 * ix[ n ][ 2 ];
      55           0 :         low_Q13 = silk_stereo_pred_quant_Q13[ ix[ n ][ 0 ] ];
      56           0 :         step_Q13 = silk_SMULWB( silk_stereo_pred_quant_Q13[ ix[ n ][ 0 ] + 1 ] - low_Q13,
      57             :             SILK_FIX_CONST( 0.5 / STEREO_QUANT_SUB_STEPS, 16 ) );
      58           0 :         pred_Q13[ n ] = silk_SMLABB( low_Q13, step_Q13, 2 * ix[ n ][ 1 ] + 1 );
      59             :     }
      60             : 
      61             :     /* Subtract second from first predictor (helps when actually applying these) */
      62           0 :     pred_Q13[ 0 ] -= pred_Q13[ 1 ];
      63           0 : }
      64             : 
      65             : /* Decode mid-only flag */
      66           0 : void silk_stereo_decode_mid_only(
      67             :     ec_dec                      *psRangeDec,                    /* I/O  Compressor data structure                   */
      68             :     opus_int                    *decode_only_mid                /* O    Flag that only mid channel has been coded   */
      69             : )
      70             : {
      71             :     /* Decode flag that only mid channel is coded */
      72           0 :     *decode_only_mid = ec_dec_icdf( psRangeDec, silk_stereo_only_code_mid_iCDF, 8 );
      73           0 : }