1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/media/libopus/silk/NLSF_decode.c Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,101 @@
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 +/* Predictive dequantizer for NLSF residuals */
1.38 +static OPUS_INLINE void silk_NLSF_residual_dequant( /* O Returns RD value in Q30 */
1.39 + opus_int16 x_Q10[], /* O Output [ order ] */
1.40 + const opus_int8 indices[], /* I Quantization indices [ order ] */
1.41 + const opus_uint8 pred_coef_Q8[], /* I Backward predictor coefs [ order ] */
1.42 + const opus_int quant_step_size_Q16, /* I Quantization step size */
1.43 + const opus_int16 order /* I Number of input values */
1.44 +)
1.45 +{
1.46 + opus_int i, out_Q10, pred_Q10;
1.47 +
1.48 + out_Q10 = 0;
1.49 + for( i = order-1; i >= 0; i-- ) {
1.50 + pred_Q10 = silk_RSHIFT( silk_SMULBB( out_Q10, (opus_int16)pred_coef_Q8[ i ] ), 8 );
1.51 + out_Q10 = silk_LSHIFT( indices[ i ], 10 );
1.52 + if( out_Q10 > 0 ) {
1.53 + out_Q10 = silk_SUB16( out_Q10, SILK_FIX_CONST( NLSF_QUANT_LEVEL_ADJ, 10 ) );
1.54 + } else if( out_Q10 < 0 ) {
1.55 + out_Q10 = silk_ADD16( out_Q10, SILK_FIX_CONST( NLSF_QUANT_LEVEL_ADJ, 10 ) );
1.56 + }
1.57 + out_Q10 = silk_SMLAWB( pred_Q10, (opus_int32)out_Q10, quant_step_size_Q16 );
1.58 + x_Q10[ i ] = out_Q10;
1.59 + }
1.60 +}
1.61 +
1.62 +
1.63 +/***********************/
1.64 +/* NLSF vector decoder */
1.65 +/***********************/
1.66 +void silk_NLSF_decode(
1.67 + opus_int16 *pNLSF_Q15, /* O Quantized NLSF vector [ LPC_ORDER ] */
1.68 + opus_int8 *NLSFIndices, /* I Codebook path vector [ LPC_ORDER + 1 ] */
1.69 + const silk_NLSF_CB_struct *psNLSF_CB /* I Codebook object */
1.70 +)
1.71 +{
1.72 + opus_int i;
1.73 + opus_uint8 pred_Q8[ MAX_LPC_ORDER ];
1.74 + opus_int16 ec_ix[ MAX_LPC_ORDER ];
1.75 + opus_int16 res_Q10[ MAX_LPC_ORDER ];
1.76 + opus_int16 W_tmp_QW[ MAX_LPC_ORDER ];
1.77 + opus_int32 W_tmp_Q9, NLSF_Q15_tmp;
1.78 + const opus_uint8 *pCB_element;
1.79 +
1.80 + /* Decode first stage */
1.81 + pCB_element = &psNLSF_CB->CB1_NLSF_Q8[ NLSFIndices[ 0 ] * psNLSF_CB->order ];
1.82 + for( i = 0; i < psNLSF_CB->order; i++ ) {
1.83 + pNLSF_Q15[ i ] = silk_LSHIFT( (opus_int16)pCB_element[ i ], 7 );
1.84 + }
1.85 +
1.86 + /* Unpack entropy table indices and predictor for current CB1 index */
1.87 + silk_NLSF_unpack( ec_ix, pred_Q8, psNLSF_CB, NLSFIndices[ 0 ] );
1.88 +
1.89 + /* Predictive residual dequantizer */
1.90 + silk_NLSF_residual_dequant( res_Q10, &NLSFIndices[ 1 ], pred_Q8, psNLSF_CB->quantStepSize_Q16, psNLSF_CB->order );
1.91 +
1.92 + /* Weights from codebook vector */
1.93 + silk_NLSF_VQ_weights_laroia( W_tmp_QW, pNLSF_Q15, psNLSF_CB->order );
1.94 +
1.95 + /* Apply inverse square-rooted weights and add to output */
1.96 + for( i = 0; i < psNLSF_CB->order; i++ ) {
1.97 + W_tmp_Q9 = silk_SQRT_APPROX( silk_LSHIFT( (opus_int32)W_tmp_QW[ i ], 18 - NLSF_W_Q ) );
1.98 + NLSF_Q15_tmp = silk_ADD32( pNLSF_Q15[ i ], silk_DIV32_16( silk_LSHIFT( (opus_int32)res_Q10[ i ], 14 ), W_tmp_Q9 ) );
1.99 + pNLSF_Q15[ i ] = (opus_int16)silk_LIMIT( NLSF_Q15_tmp, 0, 32767 );
1.100 + }
1.101 +
1.102 + /* NLSF stabilization */
1.103 + silk_NLSF_stabilize( pNLSF_Q15, psNLSF_CB->deltaMin_Q15, psNLSF_CB->order );
1.104 +}
