Tristan Matthews | 0a329cc | 2013-07-17 13:20:14 -0400 | [diff] [blame] | 1 | |
| 2 | /****************************************************************** |
| 3 | |
| 4 | iLBC Speech Coder ANSI-C Source Code |
| 5 | |
| 6 | getCBvec.c |
| 7 | |
| 8 | Copyright (C) The Internet Society (2004). |
| 9 | All Rights Reserved. |
| 10 | |
| 11 | ******************************************************************/ |
| 12 | |
| 13 | #include "iLBC_define.h" |
| 14 | #include "constants.h" |
| 15 | #include <string.h> |
| 16 | |
| 17 | /*----------------------------------------------------------------* |
| 18 | * Construct codebook vector for given index. |
| 19 | *---------------------------------------------------------------*/ |
| 20 | |
| 21 | void getCBvec( |
| 22 | |
| 23 | |
| 24 | |
| 25 | |
| 26 | |
| 27 | float *cbvec, /* (o) Constructed codebook vector */ |
| 28 | float *mem, /* (i) Codebook buffer */ |
| 29 | int index, /* (i) Codebook index */ |
| 30 | int lMem, /* (i) Length of codebook buffer */ |
| 31 | int cbveclen/* (i) Codebook vector length */ |
| 32 | ){ |
| 33 | int j, k, n, memInd, sFilt; |
| 34 | float tmpbuf[CB_MEML]; |
| 35 | int base_size; |
| 36 | int ilow, ihigh; |
| 37 | float alfa, alfa1; |
| 38 | |
| 39 | /* Determine size of codebook sections */ |
| 40 | |
| 41 | base_size=lMem-cbveclen+1; |
| 42 | |
| 43 | if (cbveclen==SUBL) { |
| 44 | base_size+=cbveclen/2; |
| 45 | } |
| 46 | |
| 47 | /* No filter -> First codebook section */ |
| 48 | |
| 49 | if (index<lMem-cbveclen+1) { |
| 50 | |
| 51 | /* first non-interpolated vectors */ |
| 52 | |
| 53 | k=index+cbveclen; |
| 54 | /* get vector */ |
| 55 | memcpy(cbvec, mem+lMem-k, cbveclen*sizeof(float)); |
| 56 | |
| 57 | } else if (index < base_size) { |
| 58 | |
| 59 | k=2*(index-(lMem-cbveclen+1))+cbveclen; |
| 60 | |
| 61 | ihigh=k/2; |
| 62 | ilow=ihigh-5; |
| 63 | |
| 64 | /* Copy first noninterpolated part */ |
| 65 | |
| 66 | memcpy(cbvec, mem+lMem-k/2, ilow*sizeof(float)); |
| 67 | |
| 68 | /* interpolation */ |
| 69 | |
| 70 | alfa1=(float)0.2; |
| 71 | alfa=0.0; |
| 72 | for (j=ilow; j<ihigh; j++) { |
| 73 | cbvec[j]=((float)1.0-alfa)*mem[lMem-k/2+j]+ |
| 74 | alfa*mem[lMem-k+j]; |
| 75 | |
| 76 | |
| 77 | |
| 78 | |
| 79 | |
| 80 | alfa+=alfa1; |
| 81 | } |
| 82 | |
| 83 | /* Copy second noninterpolated part */ |
| 84 | |
| 85 | memcpy(cbvec+ihigh, mem+lMem-k+ihigh, |
| 86 | (cbveclen-ihigh)*sizeof(float)); |
| 87 | |
| 88 | } |
| 89 | |
| 90 | /* Higher codebook section based on filtering */ |
| 91 | |
| 92 | else { |
| 93 | |
| 94 | /* first non-interpolated vectors */ |
| 95 | |
| 96 | if (index-base_size<lMem-cbveclen+1) { |
| 97 | float tempbuff2[CB_MEML+CB_FILTERLEN+1]; |
| 98 | float *pos; |
| 99 | float *pp, *pp1; |
| 100 | |
| 101 | memset(tempbuff2, 0, |
| 102 | CB_HALFFILTERLEN*sizeof(float)); |
| 103 | memcpy(&tempbuff2[CB_HALFFILTERLEN], mem, |
| 104 | lMem*sizeof(float)); |
| 105 | memset(&tempbuff2[lMem+CB_HALFFILTERLEN], 0, |
| 106 | (CB_HALFFILTERLEN+1)*sizeof(float)); |
| 107 | |
| 108 | k=index-base_size+cbveclen; |
| 109 | sFilt=lMem-k; |
| 110 | memInd=sFilt+1-CB_HALFFILTERLEN; |
| 111 | |
| 112 | /* do filtering */ |
| 113 | pos=cbvec; |
| 114 | memset(pos, 0, cbveclen*sizeof(float)); |
| 115 | for (n=0; n<cbveclen; n++) { |
| 116 | pp=&tempbuff2[memInd+n+CB_HALFFILTERLEN]; |
| 117 | pp1=&cbfiltersTbl[CB_FILTERLEN-1]; |
| 118 | for (j=0; j<CB_FILTERLEN; j++) { |
| 119 | (*pos)+=(*pp++)*(*pp1--); |
| 120 | } |
| 121 | pos++; |
| 122 | } |
| 123 | } |
| 124 | |
| 125 | /* interpolated vectors */ |
| 126 | |
| 127 | else { |
| 128 | |
| 129 | |
| 130 | |
| 131 | |
| 132 | |
| 133 | float tempbuff2[CB_MEML+CB_FILTERLEN+1]; |
| 134 | |
| 135 | float *pos; |
| 136 | float *pp, *pp1; |
| 137 | int i; |
| 138 | |
| 139 | memset(tempbuff2, 0, |
| 140 | CB_HALFFILTERLEN*sizeof(float)); |
| 141 | memcpy(&tempbuff2[CB_HALFFILTERLEN], mem, |
| 142 | lMem*sizeof(float)); |
| 143 | memset(&tempbuff2[lMem+CB_HALFFILTERLEN], 0, |
| 144 | (CB_HALFFILTERLEN+1)*sizeof(float)); |
| 145 | |
| 146 | k=2*(index-base_size- |
| 147 | (lMem-cbveclen+1))+cbveclen; |
| 148 | sFilt=lMem-k; |
| 149 | memInd=sFilt+1-CB_HALFFILTERLEN; |
| 150 | |
| 151 | /* do filtering */ |
| 152 | pos=&tmpbuf[sFilt]; |
| 153 | memset(pos, 0, k*sizeof(float)); |
| 154 | for (i=0; i<k; i++) { |
| 155 | pp=&tempbuff2[memInd+i+CB_HALFFILTERLEN]; |
| 156 | pp1=&cbfiltersTbl[CB_FILTERLEN-1]; |
| 157 | for (j=0; j<CB_FILTERLEN; j++) { |
| 158 | (*pos)+=(*pp++)*(*pp1--); |
| 159 | } |
| 160 | pos++; |
| 161 | } |
| 162 | |
| 163 | ihigh=k/2; |
| 164 | ilow=ihigh-5; |
| 165 | |
| 166 | /* Copy first noninterpolated part */ |
| 167 | |
| 168 | memcpy(cbvec, tmpbuf+lMem-k/2, |
| 169 | ilow*sizeof(float)); |
| 170 | |
| 171 | /* interpolation */ |
| 172 | |
| 173 | alfa1=(float)0.2; |
| 174 | alfa=0.0; |
| 175 | for (j=ilow; j<ihigh; j++) { |
| 176 | cbvec[j]=((float)1.0-alfa)* |
| 177 | tmpbuf[lMem-k/2+j]+alfa*tmpbuf[lMem-k+j]; |
| 178 | alfa+=alfa1; |
| 179 | } |
| 180 | |
| 181 | |
| 182 | |
| 183 | |
| 184 | |
| 185 | |
| 186 | /* Copy second noninterpolated part */ |
| 187 | |
| 188 | memcpy(cbvec+ihigh, tmpbuf+lMem-k+ihigh, |
| 189 | (cbveclen-ihigh)*sizeof(float)); |
| 190 | } |
| 191 | } |
| 192 | } |
| 193 | |