/* * Copyright (c) 2011 The WebRTC project authors. All Rights Reserved. * * Use of this source code is governed by a BSD-style license * that can be found in the LICENSE file in the root of the source * tree. An additional intellectual property rights grant can be found * in the file PATENTS. All contributing project authors may * be found in the AUTHORS file in the root of the source tree. */ /****************************************************************** iLBC Speech Coder ANSI-C Source Code WebRtcIlbcfix_AbsQuant.c ******************************************************************/ #include "defines.h" #include "constants.h" #include "abs_quant_loop.h" /*----------------------------------------------------------------* * predictive noise shaping encoding of scaled start state * (subrutine for WebRtcIlbcfix_StateSearch) *---------------------------------------------------------------*/ void WebRtcIlbcfix_AbsQuant( iLBC_Enc_Inst_t *iLBCenc_inst, /* (i) Encoder instance */ iLBC_bits *iLBC_encbits, /* (i/o) Encoded bits (outputs idxForMax and idxVec, uses state_first as input) */ WebRtc_Word16 *in, /* (i) vector to encode */ WebRtc_Word16 *weightDenum /* (i) denominator of synthesis filter */ ) { WebRtc_Word16 *syntOut; WebRtc_Word16 quantLen[2]; /* Stack based */ WebRtc_Word16 syntOutBuf[LPC_FILTERORDER+STATE_SHORT_LEN_30MS]; WebRtc_Word16 in_weightedVec[STATE_SHORT_LEN_30MS+LPC_FILTERORDER]; WebRtc_Word16 *in_weighted = &in_weightedVec[LPC_FILTERORDER]; /* Initialize the buffers */ WebRtcSpl_MemSetW16(syntOutBuf, 0, LPC_FILTERORDER+STATE_SHORT_LEN_30MS); syntOut = &syntOutBuf[LPC_FILTERORDER]; /* Start with zero state */ WebRtcSpl_MemSetW16(in_weightedVec, 0, LPC_FILTERORDER); /* Perform the quantization loop in two sections of length quantLen[i], where the perceptual weighting filter is updated at the subframe border */ if (iLBC_encbits->state_first) { quantLen[0]=SUBL; quantLen[1]=iLBCenc_inst->state_short_len-SUBL; } else { quantLen[0]=iLBCenc_inst->state_short_len-SUBL; quantLen[1]=SUBL; } /* Calculate the weighted residual, switch perceptual weighting filter at the subframe border */ WebRtcSpl_FilterARFastQ12( in, in_weighted, weightDenum, LPC_FILTERORDER+1, quantLen[0]); WebRtcSpl_FilterARFastQ12( &in[quantLen[0]], &in_weighted[quantLen[0]], &weightDenum[LPC_FILTERORDER+1], LPC_FILTERORDER+1, quantLen[1]); WebRtcIlbcfix_AbsQuantLoop( syntOut, in_weighted, weightDenum, quantLen, iLBC_encbits->idxVec); }