summaryrefslogtreecommitdiffstats
path: root/media/libopus/silk/NLSF_decode.c
diff options
context:
space:
mode:
Diffstat (limited to 'media/libopus/silk/NLSF_decode.c')
-rw-r--r--media/libopus/silk/NLSF_decode.c101
1 files changed, 101 insertions, 0 deletions
diff --git a/media/libopus/silk/NLSF_decode.c b/media/libopus/silk/NLSF_decode.c
new file mode 100644
index 000000000..9f715060b
--- /dev/null
+++ b/media/libopus/silk/NLSF_decode.c
@@ -0,0 +1,101 @@
+/***********************************************************************
+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"
+
+/* Predictive dequantizer for NLSF residuals */
+static OPUS_INLINE void silk_NLSF_residual_dequant( /* O Returns RD value in Q30 */
+ opus_int16 x_Q10[], /* O Output [ order ] */
+ const opus_int8 indices[], /* I Quantization indices [ order ] */
+ const opus_uint8 pred_coef_Q8[], /* I Backward predictor coefs [ order ] */
+ const opus_int quant_step_size_Q16, /* I Quantization step size */
+ const opus_int16 order /* I Number of input values */
+)
+{
+ opus_int i, out_Q10, pred_Q10;
+
+ out_Q10 = 0;
+ for( i = order-1; i >= 0; i-- ) {
+ pred_Q10 = silk_RSHIFT( silk_SMULBB( out_Q10, (opus_int16)pred_coef_Q8[ i ] ), 8 );
+ out_Q10 = silk_LSHIFT( indices[ i ], 10 );
+ if( out_Q10 > 0 ) {
+ out_Q10 = silk_SUB16( out_Q10, SILK_FIX_CONST( NLSF_QUANT_LEVEL_ADJ, 10 ) );
+ } else if( out_Q10 < 0 ) {
+ out_Q10 = silk_ADD16( out_Q10, SILK_FIX_CONST( NLSF_QUANT_LEVEL_ADJ, 10 ) );
+ }
+ out_Q10 = silk_SMLAWB( pred_Q10, (opus_int32)out_Q10, quant_step_size_Q16 );
+ x_Q10[ i ] = out_Q10;
+ }
+}
+
+
+/***********************/
+/* NLSF vector decoder */
+/***********************/
+void silk_NLSF_decode(
+ opus_int16 *pNLSF_Q15, /* O Quantized NLSF vector [ LPC_ORDER ] */
+ opus_int8 *NLSFIndices, /* I Codebook path vector [ LPC_ORDER + 1 ] */
+ const silk_NLSF_CB_struct *psNLSF_CB /* I Codebook object */
+)
+{
+ opus_int i;
+ opus_uint8 pred_Q8[ MAX_LPC_ORDER ];
+ opus_int16 ec_ix[ MAX_LPC_ORDER ];
+ opus_int16 res_Q10[ MAX_LPC_ORDER ];
+ opus_int16 W_tmp_QW[ MAX_LPC_ORDER ];
+ opus_int32 W_tmp_Q9, NLSF_Q15_tmp;
+ const opus_uint8 *pCB_element;
+
+ /* Decode first stage */
+ pCB_element = &psNLSF_CB->CB1_NLSF_Q8[ NLSFIndices[ 0 ] * psNLSF_CB->order ];
+ for( i = 0; i < psNLSF_CB->order; i++ ) {
+ pNLSF_Q15[ i ] = silk_LSHIFT( (opus_int16)pCB_element[ i ], 7 );
+ }
+
+ /* Unpack entropy table indices and predictor for current CB1 index */
+ silk_NLSF_unpack( ec_ix, pred_Q8, psNLSF_CB, NLSFIndices[ 0 ] );
+
+ /* Predictive residual dequantizer */
+ silk_NLSF_residual_dequant( res_Q10, &NLSFIndices[ 1 ], pred_Q8, psNLSF_CB->quantStepSize_Q16, psNLSF_CB->order );
+
+ /* Weights from codebook vector */
+ silk_NLSF_VQ_weights_laroia( W_tmp_QW, pNLSF_Q15, psNLSF_CB->order );
+
+ /* Apply inverse square-rooted weights and add to output */
+ for( i = 0; i < psNLSF_CB->order; i++ ) {
+ W_tmp_Q9 = silk_SQRT_APPROX( silk_LSHIFT( (opus_int32)W_tmp_QW[ i ], 18 - NLSF_W_Q ) );
+ NLSF_Q15_tmp = silk_ADD32( pNLSF_Q15[ i ], silk_DIV32_16( silk_LSHIFT( (opus_int32)res_Q10[ i ], 14 ), W_tmp_Q9 ) );
+ pNLSF_Q15[ i ] = (opus_int16)silk_LIMIT( NLSF_Q15_tmp, 0, 32767 );
+ }
+
+ /* NLSF stabilization */
+ silk_NLSF_stabilize( pNLSF_Q15, psNLSF_CB->deltaMin_Q15, psNLSF_CB->order );
+}