1 /*****************************************************************************
2 * math.c: Inverse Discrete Cosine Transform and Pulse Code Modulation
3 *****************************************************************************
4 * Copyright (C) 1999, 2000 VideoLAN
5 * $Id: math.c,v 1.3 2002/08/17 15:35:10 fenrir Exp $
7 * Authors: Michel Kaempf <maxx@via.ecp.fr>
8 * Michel Lespinasse <walken@via.ecp.fr>
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2 of the License, or
13 * (at your option) any later version.
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU General Public License for more details.
20 * You should have received a copy of the GNU General Public License
21 * along with this program; if not, write to the Free Software
22 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111, USA.
23 *****************************************************************************/
29 /*****************************************************************************
30 * DCT32: Fast 32 points Discrete Cosine Transform
31 *****************************************************************************
32 * 289 additions and multiplications
33 * F(u)=alpha(u)*SUM(x=0, x<N) f(x)*cos((2x+1)u*pi/2N)
34 * where alpha(u) = sqrt(2)/N if u=0, 2/N otherwise.
35 * See fastdct.ps, and fast.tar.gz for a (Fortran :) implementation.
36 *****************************************************************************/
38 void DCT32( adec_bank_t *b, float *x )
40 /* cosine coefficients */
41 static const float c2 = .70710678118655;
42 static const float c3 = .54119610014620;
43 static const float c4 = -1.3065629648764;
44 static const float c5 = .50979557910416;
45 static const float c6 = .89997622313642;
46 static const float c7 = -2.5629154477415;
47 static const float c8 = -.60134488693505;
48 static const float c9 = .50241928618816;
49 static const float c10 = .56694403481636;
50 static const float c11 = .78815462345125;
51 static const float c12 = 1.7224470982383;
52 static const float c13 = -5.1011486186892;
53 static const float c14 = -1.0606776859903;
54 static const float c15 = -.64682178335999;
55 static const float c16 = -.52249861493969;
56 static const float c17 = .50060299823520;
57 static const float c18 = .51544730992262;
58 static const float c19 = .55310389603444;
59 static const float c20 = .62250412303566;
60 static const float c21 = .74453627100230;
61 static const float c22 = .97256823786196;
62 static const float c23 = 1.4841646163142;
63 static const float c24 = 3.4076084184687;
64 static const float c25 = -10.190008123548;
65 static const float c26 = -2.0577810099534;
66 static const float c27 = -1.1694399334329;
67 static const float c28 = -.83934964541553;
68 static const float c29 = -.67480834145501;
69 static const float c30 = -.58293496820613;
70 static const float c31 = -.53104259108978;
71 static const float c32 = -.50547095989754;
73 /* temporary variables */
74 float t1 , t2 , t3 , t4 , t5 , t6 , t7 , t8 ,
75 t9 , t10 , t11 , t12 , t13 , t14 , t15 , t16 ,
76 t17 , t18 , t19 , t20 , t21 , t22 , t23 , t24 ,
77 t25 , t26 , t27 , t28 , t29 , t30 , t31 , t32 ,
78 tt1 , tt2 , tt3 , tt4 , tt5 , tt6 , tt7 , tt8 ,
79 tt9 , tt10, tt11, tt12, tt13, tt14, tt15, tt16,
80 tt17, tt18, tt19, tt20, tt21, tt22, tt23, tt24,
81 tt25, tt26, tt27, tt28, tt29, tt30, tt31, tt32, *y;
83 /* We unrolled the loops */
84 /* Odd-even ordering is integrated before the 1st stage */
85 t17 = c17 * (x[0] - x[31]);
87 t18 = c18 * (x[2] - x[29]);
89 t19 = c19 * (x[4] - x[27]);
91 t20 = c20 * (x[6] - x[25]);
93 t21 = c21 * (x[8] - x[23]);
95 t22 = c22 * (x[10] - x[21]);
97 t23 = c23 * (x[12] - x[19]);
99 t24 = c24 * (x[14] - x[17]);
101 t25 = c25 * (x[16] - x[15]);
103 t26 = c26 * (x[18] - x[13]);
105 t27 = c27 * (x[20] - x[11]);
107 t28 = c28 * (x[22] - x[9]);
109 t29 = c29 * (x[24] - x[7]);
111 t30 = c30 * (x[26] - x[5]);
113 t31 = c31 * (x[28] - x[3]);
115 t32 = c32 * (x[30] - x[1]);
118 tt9 = c9 * (t1 - t9);
120 tt10 = c10 * (t2 - t10);
122 tt11 = c11 * (t3 - t11);
124 tt12 = c12 * (t4 - t12);
126 tt13 = c13 * (t5 - t13);
128 tt14 = c14 * (t6 - t14);
130 tt15 = c15 * (t7 - t15);
132 tt16 = c16 * (t8 - t16);
134 tt25 = c9 * (t17 - t25);
136 tt26 = c10 * (t18 - t26);
138 tt27 = c11 * (t19 - t27);
140 tt28 = c12 * (t20 - t28);
142 tt29 = c13 * (t21 - t29);
144 tt30 = c14 * (t22 - t30);
146 tt31 = c15 * (t23 - t31);
148 tt32 = c16 * (t24 - t32);
151 t5 = c5 * (tt1 - tt5);
153 t6 = c6 * (tt2 - tt6);
155 t7 = c7 * (tt3 - tt7);
157 t8 = c8 * (tt4 - tt8);
159 t13 = c5 * (tt9 - tt13);
161 t14 = c6 * (tt10 - tt14);
163 t15 = c7 * (tt11 - tt15);
165 t16 = c8 * (tt12 - tt16);
167 t21 = c5 * (tt17 - tt21);
169 t22 = c6 * (tt18 - tt22);
171 t23 = c7 * (tt19 - tt23);
173 t24 = c8 * (tt20 - tt24);
175 t29 = c5 * (tt25 - tt29);
177 t30 = c6 * (tt26 - tt30);
179 t31 = c7 * (tt27 - tt31);
181 t32 = c8 * (tt28 - tt32);
184 tt3 = c3 * (t1 - t3);
186 tt4 = c4 * (t2 - t4);
188 tt7 = c3 * (t5 - t7);
190 tt8 = c4 * (t6 - t8);
192 tt11 = c3 * (t9 - t11);
194 tt12 = c4 * (t10 - t12);
196 tt15 = c3 * (t13 - t15);
198 tt16 = c4 * (t14 - t16);
200 tt19 = c3 * (t17 - t19);
202 tt20 = c4 * (t18 - t20);
204 tt23 = c3 * (t21 - t23);
206 tt24 = c4 * (t22 - t24);
208 tt27 = c3 * (t25 - t27);
210 tt28 = c4 * (t26 - t28);
212 tt31 = c3 * (t29 - t31);
214 tt32 = c4 * (t30 - t32);
216 /* Bit-reverse ordering is integrated after the 5th stage */
217 /* Begin to split the result of the DCT (t1 to t32) in the filter bank */
218 x = b->actual + b->pos;
219 y = (b->actual == b->v1 ? b->v2 : b->v1) + b->pos;
220 x[0] = -(y[0] = c2 * (tt1 - tt2)); /* t17 */
221 x[256] = 0; y[256] = tt1 + tt2; /* t1 */
222 t25 = c2 * (tt3 - tt4);
224 t21 = c2 * (tt5 - tt6);
226 t29 = c2 * (tt7 - tt8);
228 t19 = c2 * (tt9 - tt10);
230 t27 = c2 * (tt11 - tt12);
232 t23 = c2 * (tt13 - tt14);
234 t31 = c2 * (tt15 - tt16);
236 t18 = c2 * (tt17 - tt18);
238 t26 = c2 * (tt19 - tt20);
240 t22 = c2 * (tt21 - tt22);
242 t30 = c2 * (tt23 - tt24);
244 t20 = c2 * (tt25 - tt26);
246 t28 = c2 * (tt27 - tt28);
248 t24 = c2 * (tt29 - tt30);
250 t32 = c2 * (tt31 - tt32);
253 /* Keep on splitting the result */
254 y[384] = y[128] = t9 - (x[128] = -(x[384] = t25)); /* t25, t9 */
262 y[320] = y[192] = t5 + t13; /* t5 */
263 y[448] = y[64] = t13 + t21; /* t13 */
264 x[64] = -(x[448] = t21 - (x[192] = -(x[320] = t29))); /* t29, t21 */
274 y[288] = y[224] = t3 + t7; /* t3 */
275 y[352] = y[160] = t7 + t11; /* t7 */
276 y[416] = y[96] = t11 + t15; /* t11 */
277 y[480] = y[32] = t15 + t19; /* t15 */
278 x[32] = -(x[480] = t19 + t23); /* t19 */
279 x[96] = -(x[416] = t23 + t27); /* t23 */
280 x[160] = -(x[352] = t27 - (x[224] = -(x[288] = t31))); /* t31, t27 */
288 y[272] = y[240] = t2 + t4; /* t2 */
289 y[304] = y[208] = t4 + t6; /* t4 */
290 y[336] = y[176] = t6 + t8; /* t6 */
291 y[368] = y[144] = t8 + t10; /* t8 */
292 y[400] = y[112] = t10 + t12; /* t10 */
293 y[432] = y[80] = t12 + t14; /* t12 */
294 y[464] = y[48] = t14 + t16; /* t14 */
295 y[496] = y[16] = t16 + t18; /* t16 */
296 x[16] = -(x[496] = t18 + t20); /* t18 */
297 x[48] = -(x[464] = t20 + t22); /* t20 */
298 x[80] = -(x[432] = t22 + t24); /* t22 */
299 x[112] = -(x[400] = t24 + t26); /* t24 */
300 x[144] = -(x[368] = t26 + t28); /* t26 */
301 x[176] = -(x[336] = t28 + t30); /* t28 */
302 x[208] = -(x[304] = t30 - (x[240] = -(x[272] = t32))); /* t32, t30 */
303 /* Note that to be really complete, the DCT should multiply t1 by sqrt(2)/N
304 and t2 to t32 by 2/N, and would take 321 additions and multiplications.
305 But that's unuseful in this application. */
309 /*****************************************************************************
310 * PCM: Pulse Code Modulation
311 *****************************************************************************
312 * Compute 32 PCM samples with a convolution product
313 *****************************************************************************/
315 void PCM(adec_bank_t *b, float *p_pcm, int jump)
318 #define F -1 //-32768
319 /* These values are not in the same order as in Annex 3-B.3 of the ISO/IEC
321 static const float c[512] =
323 0.000000000 * F, -0.000442505 * F, 0.003250122 * F, -0.007003784 * F,
324 0.031082153 * F, -0.078628540 * F, 0.100311279 * F, -0.572036743 * F,
325 1.144989014 * F, 0.572036743 * F, 0.100311279 * F, 0.078628540 * F,
326 0.031082153 * F, 0.007003784 * F, 0.003250122 * F, 0.000442505 * F,
327 -0.000015259 * F, -0.000473022 * F, 0.003326416 * F, -0.007919312 * F,
328 0.030517578 * F, -0.084182739 * F, 0.090927124 * F, -0.600219727 * F,
329 1.144287109 * F, 0.543823242 * F, 0.108856201 * F, 0.073059082 * F,
330 0.031478882 * F, 0.006118774 * F, 0.003173828 * F, 0.000396729 * F,
331 -0.000015259 * F, -0.000534058 * F, 0.003387451 * F, -0.008865356 * F,
332 0.029785156 * F, -0.089706421 * F, 0.080688477 * F, -0.628295898 * F,
333 1.142211914 * F, 0.515609741 * F, 0.116577148 * F, 0.067520142 * F,
334 0.031738281 * F, 0.005294800 * F, 0.003082275 * F, 0.000366211 * F,
335 -0.000015259 * F, -0.000579834 * F, 0.003433228 * F, -0.009841919 * F,
336 0.028884888 * F, -0.095169067 * F, 0.069595337 * F, -0.656219482 * F,
337 1.138763428 * F, 0.487472534 * F, 0.123474121 * F, 0.061996460 * F,
338 0.031845093 * F, 0.004486084 * F, 0.002990723 * F, 0.000320435 * F,
339 -0.000015259 * F, -0.000625610 * F, 0.003463745 * F, -0.010848999 * F,
340 0.027801514 * F, -0.100540161 * F, 0.057617188 * F, -0.683914185 * F,
341 1.133926392 * F, 0.459472656 * F, 0.129577637 * F, 0.056533813 * F,
342 0.031814575 * F, 0.003723145 * F, 0.002899170 * F, 0.000289917 * F,
343 -0.000015259 * F, -0.000686646 * F, 0.003479004 * F, -0.011886597 * F,
344 0.026535034 * F, -0.105819702 * F, 0.044784546 * F, -0.711318970 * F,
345 1.127746582 * F, 0.431655884 * F, 0.134887695 * F, 0.051132202 * F,
346 0.031661987 * F, 0.003005981 * F, 0.002792358 * F, 0.000259399 * F,
347 -0.000015259 * F, -0.000747681 * F, 0.003479004 * F, -0.012939453 * F,
348 0.025085449 * F, -0.110946655 * F, 0.031082153 * F, -0.738372803 * F,
349 1.120223999 * F, 0.404083252 * F, 0.139450073 * F, 0.045837402 * F,
350 0.031387329 * F, 0.002334595 * F, 0.002685547 * F, 0.000244141 * F,
351 -0.000030518 * F, -0.000808716 * F, 0.003463745 * F, -0.014022827 * F,
352 0.023422241 * F, -0.115921021 * F, 0.016510010 * F, -0.765029907 * F,
353 1.111373901 * F, 0.376800537 * F, 0.143264771 * F, 0.040634155 * F,
354 0.031005859 * F, 0.001693726 * F, 0.002578735 * F, 0.000213623 * F,
355 -0.000030518 * F, -0.000885010 * F, 0.003417969 * F, -0.015121460 * F,
356 0.021575928 * F, -0.120697021 * F, 0.001068115 * F, -0.791213989 * F,
357 1.101211548 * F, 0.349868774 * F, 0.146362305 * F, 0.035552979 * F,
358 0.030532837 * F, 0.001098633 * F, 0.002456665 * F, 0.000198364 * F,
359 -0.000030518 * F, -0.000961304 * F, 0.003372192 * F, -0.016235352 * F,
360 0.019531250 * F, -0.125259399 * F, -0.015228271 * F, -0.816864014 * F,
361 1.089782715 * F, 0.323318481 * F, 0.148773193 * F, 0.030609131 * F,
362 0.029937744 * F, 0.000549316 * F, 0.002349854 * F, 0.000167847 * F,
363 -0.000030518 * F, -0.001037598 * F, 0.003280640 * F, -0.017349243 * F,
364 0.017257690 * F, -0.129562378 * F, -0.032379150 * F, -0.841949463 * F,
365 1.077117920 * F, 0.297210693 * F, 0.150497437 * F, 0.025817871 * F,
366 0.029281616 * F, 0.000030518 * F, 0.002243042 * F, 0.000152588 * F,
367 -0.000045776 * F, -0.001113892 * F, 0.003173828 * F, -0.018463135 * F,
368 0.014801025 * F, -0.133590698 * F, -0.050354004 * F, -0.866363525 * F,
369 1.063217163 * F, 0.271591187 * F, 0.151596069 * F, 0.021179199 * F,
370 0.028533936 * F, -0.000442505 * F, 0.002120972 * F, 0.000137329 * F,
371 -0.000045776 * F, -0.001205444 * F, 0.003051758 * F, -0.019577026 * F,
372 0.012115479 * F, -0.137298584 * F, -0.069168091 * F, -0.890090942 * F,
373 1.048156738 * F, 0.246505737 * F, 0.152069092 * F, 0.016708374 * F,
374 0.027725220 * F, -0.000869751 * F, 0.002014160 * F, 0.000122070 * F,
375 -0.000061035 * F, -0.001296997 * F, 0.002883911 * F, -0.020690918 * F,
376 0.009231567 * F, -0.140670776 * F, -0.088775635 * F, -0.913055420 * F,
377 1.031936646 * F, 0.221984863 * F, 0.151962280 * F, 0.012420654 * F,
378 0.026840210 * F, -0.001266479 * F, 0.001907349 * F, 0.000106812 * F,
379 -0.000061035 * F, -0.001388550 * F, 0.002700806 * F, -0.021789551 * F,
380 0.006134033 * F, -0.143676758 * F, -0.109161377 * F, -0.935195923 * F,
381 1.014617920 * F, 0.198059082 * F, 0.151306152 * F, 0.008316040 * F,
382 0.025909424 * F, -0.001617432 * F, 0.001785278 * F, 0.000106812 * F,
383 -0.000076294 * F, -0.001480103 * F, 0.002487183 * F, -0.022857666 * F,
384 0.002822876 * F, -0.146255493 * F, -0.130310059 * F, -0.956481934 * F,
385 0.996246338 * F, 0.174789429 * F, 0.150115967 * F, 0.004394531 * F,
386 0.024932861 * F, -0.001937866 * F, 0.001693726 * F, 0.000091553 * F,
387 -0.000076294 * F, -0.001586914 * F, 0.002227783 * F, -0.023910522 * F,
388 -0.000686646 * F, -0.148422241 * F, -0.152206421 * F, -0.976852417 * F,
389 0.976852417 * F, 0.152206421 * F, 0.148422241 * F, 0.000686646 * F,
390 0.023910522 * F, -0.002227783 * F, 0.001586914 * F, 0.000076294 * F,
391 -0.000091553 * F, -0.001693726 * F, 0.001937866 * F, -0.024932861 * F,
392 -0.004394531 * F, -0.150115967 * F, -0.174789429 * F, -0.996246338 * F,
393 0.956481934 * F, 0.130310059 * F, 0.146255493 * F, -0.002822876 * F,
394 0.022857666 * F, -0.002487183 * F, 0.001480103 * F, 0.000076294 * F,
395 -0.000106812 * F, -0.001785278 * F, 0.001617432 * F, -0.025909424 * F,
396 -0.008316040 * F, -0.151306152 * F, -0.198059082 * F, -1.014617920 * F,
397 0.935195923 * F, 0.109161377 * F, 0.143676758 * F, -0.006134033 * F,
398 0.021789551 * F, -0.002700806 * F, 0.001388550 * F, 0.000061035 * F,
399 -0.000106812 * F, -0.001907349 * F, 0.001266479 * F, -0.026840210 * F,
400 -0.012420654 * F, -0.151962280 * F, -0.221984863 * F, -1.031936646 * F,
401 0.913055420 * F, 0.088775635 * F, 0.140670776 * F, -0.009231567 * F,
402 0.020690918 * F, -0.002883911 * F, 0.001296997 * F, 0.000061035 * F,
403 -0.000122070 * F, -0.002014160 * F, 0.000869751 * F, -0.027725220 * F,
404 -0.016708374 * F, -0.152069092 * F, -0.246505737 * F, -1.048156738 * F,
405 0.890090942 * F, 0.069168091 * F, 0.137298584 * F, -0.012115479 * F,
406 0.019577026 * F, -0.003051758 * F, 0.001205444 * F, 0.000045776 * F,
407 -0.000137329 * F, -0.002120972 * F, 0.000442505 * F, -0.028533936 * F,
408 -0.021179199 * F, -0.151596069 * F, -0.271591187 * F, -1.063217163 * F,
409 0.866363525 * F, 0.050354004 * F, 0.133590698 * F, -0.014801025 * F,
410 0.018463135 * F, -0.003173828 * F, 0.001113892 * F, 0.000045776 * F,
411 -0.000152588 * F, -0.002243042 * F, -0.000030518 * F, -0.029281616 * F,
412 -0.025817871 * F, -0.150497437 * F, -0.297210693 * F, -1.077117920 * F,
413 0.841949463 * F, 0.032379150 * F, 0.129562378 * F, -0.017257690 * F,
414 0.017349243 * F, -0.003280640 * F, 0.001037598 * F, 0.000030518 * F,
415 -0.000167847 * F, -0.002349854 * F, -0.000549316 * F, -0.029937744 * F,
416 -0.030609131 * F, -0.148773193 * F, -0.323318481 * F, -1.089782715 * F,
417 0.816864014 * F, 0.015228271 * F, 0.125259399 * F, -0.019531250 * F,
418 0.016235352 * F, -0.003372192 * F, 0.000961304 * F, 0.000030518 * F,
419 -0.000198364 * F, -0.002456665 * F, -0.001098633 * F, -0.030532837 * F,
420 -0.035552979 * F, -0.146362305 * F, -0.349868774 * F, -1.101211548 * F,
421 0.791213989 * F, -0.001068115 * F, 0.120697021 * F, -0.021575928 * F,
422 0.015121460 * F, -0.003417969 * F, 0.000885010 * F, 0.000030518 * F,
423 -0.000213623 * F, -0.002578735 * F, -0.001693726 * F, -0.031005859 * F,
424 -0.040634155 * F, -0.143264771 * F, -0.376800537 * F, -1.111373901 * F,
425 0.765029907 * F, -0.016510010 * F, 0.115921021 * F, -0.023422241 * F,
426 0.014022827 * F, -0.003463745 * F, 0.000808716 * F, 0.000030518 * F,
427 -0.000244141 * F, -0.002685547 * F, -0.002334595 * F, -0.031387329 * F,
428 -0.045837402 * F, -0.139450073 * F, -0.404083252 * F, -1.120223999 * F,
429 0.738372803 * F, -0.031082153 * F, 0.110946655 * F, -0.025085449 * F,
430 0.012939453 * F, -0.003479004 * F, 0.000747681 * F, 0.000015259 * F,
431 -0.000259399 * F, -0.002792358 * F, -0.003005981 * F, -0.031661987 * F,
432 -0.051132202 * F, -0.134887695 * F, -0.431655884 * F, -1.127746582 * F,
433 0.711318970 * F, -0.044784546 * F, 0.105819702 * F, -0.026535034 * F,
434 0.011886597 * F, -0.003479004 * F, 0.000686646 * F, 0.000015259 * F,
435 -0.000289917 * F, -0.002899170 * F, -0.003723145 * F, -0.031814575 * F,
436 -0.056533813 * F, -0.129577637 * F, -0.459472656 * F, -1.133926392 * F,
437 0.683914185 * F, -0.057617188 * F, 0.100540161 * F, -0.027801514 * F,
438 0.010848999 * F, -0.003463745 * F, 0.000625610 * F, 0.000015259 * F,
439 -0.000320435 * F, -0.002990723 * F, -0.004486084 * F, -0.031845093 * F,
440 -0.061996460 * F, -0.123474121 * F, -0.487472534 * F, -1.138763428 * F,
441 0.656219482 * F, -0.069595337 * F, 0.095169067 * F, -0.028884888 * F,
442 0.009841919 * F, -0.003433228 * F, 0.000579834 * F, 0.000015259 * F,
443 -0.000366211 * F, -0.003082275 * F, -0.005294800 * F, -0.031738281 * F,
444 -0.067520142 * F, -0.116577148 * F, -0.515609741 * F, -1.142211914 * F,
445 0.628295898 * F, -0.080688477 * F, 0.089706421 * F, -0.029785156 * F,
446 0.008865356 * F, -0.003387451 * F, 0.000534058 * F, 0.000015259 * F,
447 -0.000396729 * F, -0.003173828 * F, -0.006118774 * F, -0.031478882 * F,
448 -0.073059082 * F, -0.108856201 * F, -0.543823242 * F, -1.144287109 * F,
449 0.600219727 * F, -0.090927124 * F, 0.084182739 * F, -0.030517578 * F,
450 0.007919312 * F, -0.003326416 * F, 0.000473022 * F, 0.000015259 * F
481 if ((tmp += *f++ * *v) > 1.0)
483 /* ceiling saturation */
488 /* floor saturation */
519 if ((tmp += *f++ * *v) > 1.0)
555 if ((tmp += *f++ * *v) > 1.0)
591 if ((tmp += *f++ * *v) > 1.0)
627 if ((tmp += *f++ * *v) > 1.0)
663 if ((tmp += *f++ * *v) > 1.0)
699 if ((tmp += *f++ * *v) > 1.0)
735 if ((tmp += *f++ * *v) > 1.0)
771 if ((tmp += *f++ * *v) > 1.0)
807 if ((tmp += *f++ * *v) > 1.0)
843 if ((tmp += *f++ * *v) > 1.0)
879 if ((tmp += *f++ * *v) > 1.0)
915 if ((tmp += *f++ * *v) > 1.0)
951 if ((tmp += *f++ * *v) > 1.0)
987 if ((tmp += *f++ * *v) > 1.0)
1005 for (i=0; i<32; i++)
1022 if ((tmp += *f++ * *v) > 1.0)
1026 else if (tmp < -1.0)
1040 /* Set the next position in the filter bank */
1043 b->actual = (b->actual == b->v1 ? b->v2 : b->v1);