1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
|
/* (C) 2007 Jean-Marc Valin, CSIRO
*/
/*
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 the Xiph.org Foundation nor the names of its
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 FOUNDATION 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.
*/
#include <math.h>
#include <stdlib.h>
#include "cwrs.h"
/* Algebraic pulse-base quantiser. The signal x is replaced by the sum of the pitch
a combination of pulses such that its norm is still equal to 1 */
void alg_quant(float *x, int N, int K, float *p)
{
float y[N];
int i,j;
float xy = 0;
float yy = 0;
float yp = 0;
float Rpp=0;
float gain=0;
for (j=0;j<N;j++)
Rpp += p[j]*p[j];
for (i=0;i<N;i++)
y[i] = 0;
for (i=0;i<K;i++)
{
int best_id=0;
float max_val=-1e10;
float best_xy=0, best_yy=0, best_yp = 0;
for (j=0;j<N;j++)
{
float tmp_xy, tmp_yy, tmp_yp;
float score;
float g;
tmp_xy = xy + fabs(x[j]);
tmp_yy = yy + 2*fabs(y[j]) + 1;
if (x[j]>0)
tmp_yp = yp + p[j];
else
tmp_yp = yp - p[j];
g = (sqrt(tmp_yp*tmp_yp + tmp_yy - tmp_yy*Rpp) - tmp_yp)/tmp_yy;
score = 2*g*tmp_xy - g*g*tmp_yy;
if (score>max_val)
{
max_val = score;
best_id = j;
best_xy = tmp_xy;
best_yy = tmp_yy;
best_yp = tmp_yp;
gain = g;
}
}
xy = best_xy;
yy = best_yy;
yp = best_yp;
if (x[best_id]>0)
y[best_id] += 1;
else
y[best_id] -= 1;
}
for (i=0;i<N;i++)
x[i] = p[i]+gain*y[i];
}
/* Improved algebraic pulse-base quantiser. The signal x is replaced by the sum of the pitch
a combination of pulses such that its norm is still equal to 1. The only difference with
the quantiser above is that the search is more complete. */
int alg_quant2(float *x, int N, int K, float *p)
{
int L = 5;
//float tata[200];
float y[L][N];
int iy[L][N];
//float tata2[200];
float ny[L][N];
int iny[L][N];
int i, j, m;
float xy[L], nxy[L];
float yy[L], nyy[L];
float yp[L], nyp[L];
float best_scores[L];
float Rpp=0, Rxp=0;
float gain[L];
int maxL = 1;
float alpha = .9;
for (j=0;j<N;j++)
Rpp += p[j]*p[j];
for (j=0;j<N;j++)
Rxp += x[j]*p[j];
for (m=0;m<L;m++)
for (i=0;i<N;i++)
y[m][i] = 0;
for (m=0;m<L;m++)
for (i=0;i<N;i++)
ny[m][i] = 0;
for (m=0;m<L;m++)
for (i=0;i<N;i++)
iy[m][i] = iny[m][i] = 0;
for (m=0;m<L;m++)
xy[m] = yy[m] = yp[m] = gain[m] = 0;
for (i=0;i<K;i++)
{
int L2 = L;
if (L>maxL)
{
L2 = maxL;
maxL *= N;
}
for (m=0;m<L;m++)
best_scores[m] = -1e10;
for (m=0;m<L2;m++)
{
for (j=0;j<N;j++)
{
int sign;
for (sign=-1;sign<=1;sign+=2)
{
if (iy[m][j]*sign < 0)
continue;
//fprintf (stderr, "%d/%d %d/%d %d/%d\n", i, K, m, L2, j, N);
float tmp_xy, tmp_yy, tmp_yp;
float score;
float g;
float s = sign;
tmp_xy = xy[m] + s*x[j] - alpha*s*p[j]*Rxp;
tmp_yy = yy[m] + 2*s*y[m][j] + 1 +alpha*alpha*p[j]*p[j]*Rpp - 2*alpha*s*p[j]*yp[m] - 2*alpha*p[j]*p[j];
tmp_yp = yp[m] + s*p[j] *(1-alpha*Rpp);
g = (sqrt(tmp_yp*tmp_yp + tmp_yy - tmp_yy*Rpp) - tmp_yp)/tmp_yy;
score = 2*g*tmp_xy - g*g*tmp_yy;
if (score>best_scores[L-1])
{
int k, n;
int id = L-1;
while (id > 0 && score > best_scores[id-1])
id--;
for (k=L-1;k>id;k--)
{
nxy[k] = nxy[k-1];
nyy[k] = nyy[k-1];
nyp[k] = nyp[k-1];
//fprintf(stderr, "%d %d \n", N, k);
for (n=0;n<N;n++)
ny[k][n] = ny[k-1][n];
for (n=0;n<N;n++)
iny[k][n] = iny[k-1][n];
gain[k] = gain[k-1];
best_scores[k] = best_scores[k-1];
}
nxy[id] = tmp_xy;
nyy[id] = tmp_yy;
nyp[id] = tmp_yp;
gain[id] = g;
for (n=0;n<N;n++)
ny[id][n] = y[m][n];
ny[id][j] += s;
for (n=0;n<N;n++)
ny[id][n] -= alpha*s*p[j]*p[n];
for (n=0;n<N;n++)
iny[id][n] = iy[m][n];
if (s>0)
iny[id][j] += 1;
else
iny[id][j] -= 1;
best_scores[id] = score;
}
}
}
}
int k,n;
for (k=0;k<L;k++)
{
xy[k] = nxy[k];
yy[k] = nyy[k];
yp[k] = nyp[k];
for (n=0;n<N;n++)
y[k][n] = ny[k][n];
for (n=0;n<N;n++)
iy[k][n] = iny[k][n];
}
}
for (i=0;i<N;i++)
x[i] = p[i]+gain[0]*y[0][i];
if (0) {
float E=1e-15;
int ABS = 0;
for (i=0;i<N;i++)
ABS += abs(iy[0][i]);
//if (K != ABS)
// printf ("%d %d\n", K, ABS);
for (i=0;i<N;i++)
E += x[i]*x[i];
//printf ("%f\n", E);
E = 1/sqrt(E);
for (i=0;i<N;i++)
x[i] *= E;
}
int comb[K];
int signs[K];
pulse2comb(N, K, comb, signs, iy[0]);
return icwrs(N, K, comb, signs);
}
/* Just replace the band with noise of unit energy */
void noise_quant(float *x, int N, int K, float *p)
{
int i;
float E = 1e-10;
for (i=0;i<N;i++)
{
x[i] = (rand()%1000)/500.-1;
E += x[i]*x[i];
}
E = 1./sqrt(E);
for (i=0;i<N;i++)
{
x[i] *= E;
}
}
static const float pg[5] = {1.f, .82f, .75f, 0.7f, 0.6f};
/* Finds the right offset into Y and copy it */
void copy_quant(float *x, int N, int K, float *Y, int B, int N0)
{
int i,j;
int best=0;
float best_score=0;
float s = 1;
float E;
for (i=0;i<N0*B-N;i+=B)
{
int j;
float xy=0, yy=0;
float score;
for (j=0;j<N;j++)
{
xy += x[j]*Y[i+j];
yy += Y[i+j]*Y[i+j];
}
score = xy*xy/(.001+yy);
if (score > best_score)
{
best_score = score;
best = i;
if (xy>0)
s = 1;
else
s = -1;
}
}
//printf ("%d %f\n", best, best_score);
if (K==0)
{
E = 1e-10;
for (j=0;j<N;j++)
{
x[j] = s*Y[best+j];
E += x[j]*x[j];
}
E = 1/sqrt(E);
for (j=0;j<N;j++)
x[j] *= E;
} else {
float P[N];
float pred_gain;
if (K>4)
pred_gain = .5;
else
pred_gain = pg[K];
E = 1e-10;
for (j=0;j<N;j++)
{
P[j] = s*Y[best+j];
E += P[j]*P[j];
}
E = .8/sqrt(E);
for (j=0;j<N;j++)
P[j] *= E;
alg_quant2(x, N, K, P);
}
}
|