Add copy of opus library in deps/third_party.

opus/silk/float/process_gains_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"
+#include "tuning_parameters.h"
+
+/* Processing of gains */
+void silk_process_gains_FLP(
+    silk_encoder_state_FLP          *psEnc,                             /* I/O  Encoder state FLP                           */
+    silk_encoder_control_FLP        *psEncCtrl,                         /* I/O  Encoder control FLP                         */
+    opus_int                        condCoding                          /* I    The type of conditional coding to use       */
+)
+{
+    silk_shape_state_FLP *psShapeSt = &psEnc->sShape;
+    opus_int     k;
+    opus_int32   pGains_Q16[ MAX_NB_SUBFR ];
+    silk_float   s, InvMaxSqrVal, gain, quant_offset;
+
+    /* Gain reduction when LTP coding gain is high */
+    if( psEnc->sCmn.indices.signalType == TYPE_VOICED ) {
+        s = 1.0f - 0.5f * silk_sigmoid( 0.25f * ( psEncCtrl->LTPredCodGain - 12.0f ) );
+        for( k = 0; k < psEnc->sCmn.nb_subfr; k++ ) {
+            psEncCtrl->Gains[ k ] *= s;
+        }
+    }
+
+    /* Limit the quantized signal */
+    InvMaxSqrVal = ( silk_float )( pow( 2.0f, 0.33f * ( 21.0f - psEnc->sCmn.SNR_dB_Q7 * ( 1 / 128.0f ) ) ) / psEnc->sCmn.subfr_length );
+
+    for( k = 0; k < psEnc->sCmn.nb_subfr; k++ ) {
+        /* Soft limit on ratio residual energy and squared gains */
+        gain = psEncCtrl->Gains[ k ];
+        gain = ( silk_float )sqrt( gain * gain + psEncCtrl->ResNrg[ k ] * InvMaxSqrVal );
+        psEncCtrl->Gains[ k ] = silk_min_float( gain, 32767.0f );
+    }
+
+    /* Prepare gains for noise shaping quantization */
+    for( k = 0; k < psEnc->sCmn.nb_subfr; k++ ) {
+        pGains_Q16[ k ] = (opus_int32)( psEncCtrl->Gains[ k ] * 65536.0f );
+    }
+
+    /* Save unquantized gains and gain Index */
+    silk_memcpy( psEncCtrl->GainsUnq_Q16, pGains_Q16, psEnc->sCmn.nb_subfr * sizeof( opus_int32 ) );
+    psEncCtrl->lastGainIndexPrev = psShapeSt->LastGainIndex;
+
+    /* Quantize gains */
+    silk_gains_quant( psEnc->sCmn.indices.GainsIndices, pGains_Q16,
+            &psShapeSt->LastGainIndex, condCoding == CODE_CONDITIONALLY, psEnc->sCmn.nb_subfr );
+
+    /* Overwrite unquantized gains with quantized gains and convert back to Q0 from Q16 */
+    for( k = 0; k < psEnc->sCmn.nb_subfr; k++ ) {
+        psEncCtrl->Gains[ k ] = pGains_Q16[ k ] / 65536.0f;
+    }
+
+    /* Set quantizer offset for voiced signals. Larger offset when LTP coding gain is low or tilt is high (ie low-pass) */
+    if( psEnc->sCmn.indices.signalType == TYPE_VOICED ) {
+        if( psEncCtrl->LTPredCodGain + psEnc->sCmn.input_tilt_Q15 * ( 1.0f / 32768.0f ) > 1.0f ) {
+            psEnc->sCmn.indices.quantOffsetType = 0;
+        } else {
+            psEnc->sCmn.indices.quantOffsetType = 1;
+        }
+    }
+
+    /* Quantizer boundary adjustment */
+    quant_offset = silk_Quantization_Offsets_Q10[ psEnc->sCmn.indices.signalType >> 1 ][ psEnc->sCmn.indices.quantOffsetType ] / 1024.0f;
+    psEncCtrl->Lambda = LAMBDA_OFFSET
+                      + LAMBDA_DELAYED_DECISIONS * psEnc->sCmn.nStatesDelayedDecision
+                      + LAMBDA_SPEECH_ACT        * psEnc->sCmn.speech_activity_Q8 * ( 1.0f /  256.0f )
+                      + LAMBDA_INPUT_QUALITY     * psEncCtrl->input_quality
+                      + LAMBDA_CODING_QUALITY    * psEncCtrl->coding_quality
+                      + LAMBDA_QUANT_OFFSET      * quant_offset;
+
+    silk_assert( psEncCtrl->Lambda > 0.0f );
+    silk_assert( psEncCtrl->Lambda < 2.0f );
+}