Mercurial > hg > audiostuff

comparison intercom/ilbc/StateSearchW.c @ 2:13be24d74cd2

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
import intercom-0.4.1
author Peter Meerwald <pmeerw@cosy.sbg.ac.at>
date Fri, 25 Jun 2010 09:57:52 +0200
parents
children
comparison
equal deleted inserted replaced
1:9cadc470e3da 2:13be24d74cd2
1
2 /******************************************************************
3
4 iLBC Speech Coder ANSI-C Source Code
5
6 StateSearchW.c
7
8 Copyright (C) The Internet Society (2004).
9 All Rights Reserved.
10
11 ******************************************************************/
12
13 #include <math.h>
14 #include <string.h>
15
16 #include "iLBC_define.h"
17 #include "constants.h"
18 #include "filter.h"
19 #include "helpfun.h"
20
21 /*----------------------------------------------------------------*
22 * predictive noise shaping encoding of scaled start state
23 * (subrutine for StateSearchW)
24 *---------------------------------------------------------------*/
25
26 void AbsQuantW(iLBC_Enc_Inst_t * iLBCenc_inst,
27 /* (i) Encoder instance */
28 float *in, /* (i) vector to encode */
29 float *syntDenum, /* (i) denominator of synthesis filter */
30 float *weightDenum, /* (i) denominator of weighting filter */
31 int *out, /* (o) vector of quantizer indexes */
32 int len, /* (i) length of vector to encode and
33 vector of quantizer indexes */
34 int state_first /* (i) position of start state in the
35 80 vec */
36 )
37 {
38 float *syntOut;
39 float syntOutBuf[LPC_FILTERORDER + STATE_SHORT_LEN_30MS];
40 float toQ, xq;
41 int n;
42 int index;
43
44 /* initialization of buffer for filtering */
45
46 memset(syntOutBuf, 0, LPC_FILTERORDER * sizeof(float));
47
48
49
50
51
52
53 /* initialization of pointer for filtering */
54
55 syntOut = &syntOutBuf[LPC_FILTERORDER];
56
57 /* synthesis and weighting filters on input */
58
59 if (state_first) {
60 AllPoleFilter(in, weightDenum, SUBL, LPC_FILTERORDER);
61 } else {
62 AllPoleFilter(in, weightDenum,
63 iLBCenc_inst->state_short_len - SUBL, LPC_FILTERORDER);
64 }
65
66 /* encoding loop */
67
68 for (n = 0; n < len; n++) {
69
70 /* time update of filter coefficients */
71
72 if ((state_first) && (n == SUBL)) {
73 syntDenum += (LPC_FILTERORDER + 1);
74 weightDenum += (LPC_FILTERORDER + 1);
75
76 /* synthesis and weighting filters on input */
77 AllPoleFilter(&in[n], weightDenum, len - n, LPC_FILTERORDER);
78
79 } else if ((state_first == 0) &&
80 (n == (iLBCenc_inst->state_short_len - SUBL))) {
81 syntDenum += (LPC_FILTERORDER + 1);
82 weightDenum += (LPC_FILTERORDER + 1);
83
84 /* synthesis and weighting filters on input */
85 AllPoleFilter(&in[n], weightDenum, len - n, LPC_FILTERORDER);
86
87 }
88
89 /* prediction of synthesized and weighted input */
90
91 syntOut[n] = 0.0;
92 AllPoleFilter(&syntOut[n], weightDenum, 1, LPC_FILTERORDER);
93
94 /* quantization */
95
96 toQ = in[n] - syntOut[n];
97
98
99
100
101
102 sort_sq(&xq, &index, toQ, state_sq3Tbl, 8);
103 out[n] = index;
104 syntOut[n] = state_sq3Tbl[out[n]];
105
106 /* update of the prediction filter */
107
108 AllPoleFilter(&syntOut[n], weightDenum, 1, LPC_FILTERORDER);
109 }
110 }
111
112 /*----------------------------------------------------------------*
113 * encoding of start state
114 *---------------------------------------------------------------*/
115
116 void StateSearchW(iLBC_Enc_Inst_t * iLBCenc_inst,
117 /* (i) Encoder instance */
118 float *residual, /* (i) target residual vector */
119 float *syntDenum, /* (i) lpc synthesis filter */
120 float *weightDenum, /* (i) weighting filter denuminator */
121 int *idxForMax, /* (o) quantizer index for maximum
122 amplitude */
123 int *idxVec, /* (o) vector of quantization indexes */
124 int len, /* (i) length of all vectors */
125 int state_first /* (i) position of start state in the
126 80 vec */
127 )
128 {
129 float dtmp, maxVal;
130 float tmpbuf[LPC_FILTERORDER + 2 * STATE_SHORT_LEN_30MS];
131 float *tmp, numerator[1 + LPC_FILTERORDER];
132 float foutbuf[LPC_FILTERORDER + 2 * STATE_SHORT_LEN_30MS], *fout;
133 int k;
134 float qmax, scal;
135
136 /* initialization of buffers and filter coefficients */
137
138 memset(tmpbuf, 0, LPC_FILTERORDER * sizeof(float));
139 memset(foutbuf, 0, LPC_FILTERORDER * sizeof(float));
140 for (k = 0; k < LPC_FILTERORDER; k++) {
141 numerator[k] = syntDenum[LPC_FILTERORDER - k];
142 }
143 numerator[LPC_FILTERORDER] = syntDenum[0];
144 tmp = &tmpbuf[LPC_FILTERORDER];
145 fout = &foutbuf[LPC_FILTERORDER];
146
147 /* circular convolution with the all-pass filter */
148
149
150
151
152
153
154 memcpy(tmp, residual, len * sizeof(float));
155 memset(tmp + len, 0, len * sizeof(float));
156 ZeroPoleFilter(tmp, numerator, syntDenum, 2 * len,
157 LPC_FILTERORDER, fout);
158 for (k = 0; k < len; k++) {
159 fout[k] += fout[k + len];
160 }
161
162 /* identification of the maximum amplitude value */
163
164 maxVal = fout[0];
165 for (k = 1; k < len; k++) {
166
167 if (fout[k] * fout[k] > maxVal * maxVal) {
168 maxVal = fout[k];
169 }
170 }
171 maxVal = (float) fabs(maxVal);
172
173 /* encoding of the maximum amplitude value */
174
175 if (maxVal < 10.0) {
176 maxVal = 10.0;
177 }
178 maxVal = (float) log10(maxVal);
179 sort_sq(&dtmp, idxForMax, maxVal, state_frgqTbl, 64);
180
181 /* decoding of the maximum amplitude representation value,
182 and corresponding scaling of start state */
183
184 maxVal = state_frgqTbl[*idxForMax];
185 qmax = (float) pow(10, maxVal);
186 scal = (float) (4.5) / qmax;
187 for (k = 0; k < len; k++) {
188 fout[k] *= scal;
189 }
190
191 /* predictive noise shaping encoding of scaled start state */
192
193 AbsQuantW(iLBCenc_inst, fout, syntDenum,
194 weightDenum, idxVec, len, state_first);
195 }

Repositories maintained by Peter Meerwald, pmeerw@pmeerw.net.