Add copy of opus library in deps/third_party.

opus/silk/float/find_pred_coefs_FLP.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_FLP.h"
+
+/* Find LPC and LTP coefficients */
+void silk_find_pred_coefs_FLP(
+    silk_encoder_state_FLP          *psEnc,                             /* I/O  Encoder state FLP                           */
+    silk_encoder_control_FLP        *psEncCtrl,                         /* I/O  Encoder control FLP                         */
+    const silk_float                res_pitch[],                        /* I    Residual from pitch analysis                */
+    const silk_float                x[],                                /* I    Speech signal                               */
+    opus_int                        condCoding                          /* I    The type of conditional coding to use       */
+)
+{
+    opus_int         i;
+    silk_float       WLTP[ MAX_NB_SUBFR * LTP_ORDER * LTP_ORDER ];
+    silk_float       invGains[ MAX_NB_SUBFR ], Wght[ MAX_NB_SUBFR ];
+    opus_int16       NLSF_Q15[ MAX_LPC_ORDER ];
+    const silk_float *x_ptr;
+    silk_float       *x_pre_ptr, LPC_in_pre[ MAX_NB_SUBFR * MAX_LPC_ORDER + MAX_FRAME_LENGTH ];
+    silk_float       minInvGain;
+
+    /* Weighting for weighted least squares */
+    for( i = 0; i < psEnc->sCmn.nb_subfr; i++ ) {
+        silk_assert( psEncCtrl->Gains[ i ] > 0.0f );
+        invGains[ i ] = 1.0f / psEncCtrl->Gains[ i ];
+        Wght[ i ]     = invGains[ i ] * invGains[ i ];
+    }
+
+    if( psEnc->sCmn.indices.signalType == TYPE_VOICED ) {
+        /**********/
+        /* VOICED */
+        /**********/
+        silk_assert( psEnc->sCmn.ltp_mem_length - psEnc->sCmn.predictLPCOrder >= psEncCtrl->pitchL[ 0 ] + LTP_ORDER / 2 );
+
+        /* LTP analysis */
+        silk_find_LTP_FLP( psEncCtrl->LTPCoef, WLTP, &psEncCtrl->LTPredCodGain, res_pitch,
+            psEncCtrl->pitchL, Wght, psEnc->sCmn.subfr_length, psEnc->sCmn.nb_subfr, psEnc->sCmn.ltp_mem_length );
+
+        /* Quantize LTP gain parameters */
+        silk_quant_LTP_gains_FLP( psEncCtrl->LTPCoef, psEnc->sCmn.indices.LTPIndex, &psEnc->sCmn.indices.PERIndex,
+            WLTP, psEnc->sCmn.mu_LTP_Q9, psEnc->sCmn.LTPQuantLowComplexity, psEnc->sCmn.nb_subfr );
+
+        /* Control LTP scaling */
+        silk_LTP_scale_ctrl_FLP( psEnc, psEncCtrl, condCoding );
+
+        /* Create LTP residual */
+        silk_LTP_analysis_filter_FLP( LPC_in_pre, x - psEnc->sCmn.predictLPCOrder, psEncCtrl->LTPCoef,
+            psEncCtrl->pitchL, invGains, psEnc->sCmn.subfr_length, psEnc->sCmn.nb_subfr, psEnc->sCmn.predictLPCOrder );
+    } else {
+        /************/
+        /* UNVOICED */
+        /************/
+        /* Create signal with prepended subframes, scaled by inverse gains */
+        x_ptr     = x - psEnc->sCmn.predictLPCOrder;
+        x_pre_ptr = LPC_in_pre;
+        for( i = 0; i < psEnc->sCmn.nb_subfr; i++ ) {
+            silk_scale_copy_vector_FLP( x_pre_ptr, x_ptr, invGains[ i ],
+                psEnc->sCmn.subfr_length + psEnc->sCmn.predictLPCOrder );
+            x_pre_ptr += psEnc->sCmn.subfr_length + psEnc->sCmn.predictLPCOrder;
+            x_ptr     += psEnc->sCmn.subfr_length;
+        }
+        silk_memset( psEncCtrl->LTPCoef, 0, psEnc->sCmn.nb_subfr * LTP_ORDER * sizeof( silk_float ) );
+        psEncCtrl->LTPredCodGain = 0.0f;
+    }
+
+    /* Limit on total predictive coding gain */
+    if( psEnc->sCmn.first_frame_after_reset ) {
+        minInvGain = 1.0f / MAX_PREDICTION_POWER_GAIN_AFTER_RESET;
+    } else {        
+        minInvGain = (silk_float)pow( 2, psEncCtrl->LTPredCodGain / 3 ) /  MAX_PREDICTION_POWER_GAIN;
+        minInvGain /= 0.25f + 0.75f * psEncCtrl->coding_quality;
+    }
+
+    /* LPC_in_pre contains the LTP-filtered input for voiced, and the unfiltered input for unvoiced */
+    silk_find_LPC_FLP( &psEnc->sCmn, NLSF_Q15, LPC_in_pre, minInvGain );
+
+    /* Quantize LSFs */
+    silk_process_NLSFs_FLP( &psEnc->sCmn, psEncCtrl->PredCoef, NLSF_Q15, psEnc->sCmn.prev_NLSFq_Q15 );
+
+    /* Calculate residual energy using quantized LPC coefficients */
+    silk_residual_energy_FLP( psEncCtrl->ResNrg, LPC_in_pre, psEncCtrl->PredCoef, psEncCtrl->Gains,
+        psEnc->sCmn.subfr_length, psEnc->sCmn.nb_subfr, psEnc->sCmn.predictLPCOrder );
+
+    /* Copy to prediction struct for use in next frame for interpolation */
+    silk_memcpy( psEnc->sCmn.prev_NLSFq_Q15, NLSF_Q15, sizeof( psEnc->sCmn.prev_NLSFq_Q15 ) );
+}
+