1 /* 2 * Copyright (c) 2011 The WebRTC project authors. All Rights Reserved. 3 * 4 * Use of this source code is governed by a BSD-style license 5 * that can be found in the LICENSE file in the root of the source 6 * tree. An additional intellectual property rights grant can be found 7 * in the file PATENTS. All contributing project authors may 8 * be found in the AUTHORS file in the root of the source tree. 9 */ 10 11 /****************************************************************** 12 13 iLBC Speech Coder ANSI-C Source Code 14 15 WebRtcIlbcfix_CbConstruct.c 16 17 ******************************************************************/ 18 19 #include "defines.h" 20 #include "gain_dequant.h" 21 #include "get_cd_vec.h" 22 23 /*----------------------------------------------------------------* 24 * Construct decoded vector from codebook and gains. 25 *---------------------------------------------------------------*/ 26 27 void WebRtcIlbcfix_CbConstruct( 28 int16_t *decvector, /* (o) Decoded vector */ 29 int16_t *index, /* (i) Codebook indices */ 30 int16_t *gain_index, /* (i) Gain quantization indices */ 31 int16_t *mem, /* (i) Buffer for codevector construction */ 32 size_t lMem, /* (i) Length of buffer */ 33 size_t veclen /* (i) Length of vector */ 34 ){ 35 size_t j; 36 int16_t gain[CB_NSTAGES]; 37 /* Stack based */ 38 int16_t cbvec0[SUBL]; 39 int16_t cbvec1[SUBL]; 40 int16_t cbvec2[SUBL]; 41 int32_t a32; 42 int16_t *gainPtr; 43 44 /* gain de-quantization */ 45 46 gain[0] = WebRtcIlbcfix_GainDequant(gain_index[0], 16384, 0); 47 gain[1] = WebRtcIlbcfix_GainDequant(gain_index[1], gain[0], 1); 48 gain[2] = WebRtcIlbcfix_GainDequant(gain_index[2], gain[1], 2); 49 50 /* codebook vector construction and construction of total vector */ 51 52 /* Stack based */ 53 WebRtcIlbcfix_GetCbVec(cbvec0, mem, (size_t)index[0], lMem, veclen); 54 WebRtcIlbcfix_GetCbVec(cbvec1, mem, (size_t)index[1], lMem, veclen); 55 WebRtcIlbcfix_GetCbVec(cbvec2, mem, (size_t)index[2], lMem, veclen); 56 57 gainPtr = &gain[0]; 58 for (j=0;j<veclen;j++) { 59 a32 = (*gainPtr++) * cbvec0[j]; 60 a32 += (*gainPtr++) * cbvec1[j]; 61 a32 += (*gainPtr) * cbvec2[j]; 62 gainPtr -= 2; 63 decvector[j] = (int16_t)((a32 + 8192) >> 14); 64 } 65 66 return; 67 } 68