1 /*****************************************************************************
2 * audio_math.c: Inverse Discrete Cosine Transform and Pulse Code Modulation
4 *****************************************************************************/
5 /*****************************************************************************
7 *****************************************************************************/
9 #include <stdio.h> /* "intf_msg.h" */
10 #include <stdlib.h> /* malloc(), free() */
11 #include <netinet/in.h> /* ntohl() */
12 #include <sys/soundcard.h> /* "audio_output.h" */
21 #include "intf_msg.h" /* intf_DbgMsg(), intf_ErrMsg() */
24 #include "input_netlist.h"
25 #include "decoder_fifo.h"
27 #include "audio_output.h"
29 #include "audio_constants.h"
30 #include "audio_decoder.h"
31 #include "audio_math.h"
33 /*****************************************************************************
34 * DCT32: Fast 32 points Discrete Cosine Transform
35 *****************************************************************************
36 * 289 additions and multiplications
37 * F(u)=alpha(u)*SUM(x=0, x<N) f(x)*cos((2x+1)u*pi/2N)
38 * where alpha(u) = sqrt(2)/N if u=0, 2/N otherwise.
39 * See fastdct.ps, and fast.tar.gz for a (Fortran :) implementation.
40 *****************************************************************************/
42 void DCT32(float *x, adec_bank_t *b)
44 /* cosine coefficients */
45 static const float c2 = .70710678118655;
46 static const float c3 = .54119610014620;
47 static const float c4 = -1.3065629648764;
48 static const float c5 = .50979557910416;
49 static const float c6 = .89997622313642;
50 static const float c7 = -2.5629154477415;
51 static const float c8 = -.60134488693505;
52 static const float c9 = .50241928618816;
53 static const float c10 = .56694403481636;
54 static const float c11 = .78815462345125;
55 static const float c12 = 1.7224470982383;
56 static const float c13 = -5.1011486186892;
57 static const float c14 = -1.0606776859903;
58 static const float c15 = -.64682178335999;
59 static const float c16 = -.52249861493969;
60 static const float c17 = .50060299823520;
61 static const float c18 = .51544730992262;
62 static const float c19 = .55310389603444;
63 static const float c20 = .62250412303566;
64 static const float c21 = .74453627100230;
65 static const float c22 = .97256823786196;
66 static const float c23 = 1.4841646163142;
67 static const float c24 = 3.4076084184687;
68 static const float c25 = -10.190008123548;
69 static const float c26 = -2.0577810099534;
70 static const float c27 = -1.1694399334329;
71 static const float c28 = -.83934964541553;
72 static const float c29 = -.67480834145501;
73 static const float c30 = -.58293496820613;
74 static const float c31 = -.53104259108978;
75 static const float c32 = -.50547095989754;
77 /* temporary variables */
78 float t1 , t2 , t3 , t4 , t5 , t6 , t7 , t8 ,
79 t9 , t10 , t11 , t12 , t13 , t14 , t15 , t16 ,
80 t17 , t18 , t19 , t20 , t21 , t22 , t23 , t24 ,
81 t25 , t26 , t27 , t28 , t29 , t30 , t31 , t32 ,
82 tt1 , tt2 , tt3 , tt4 , tt5 , tt6 , tt7 , tt8 ,
83 tt9 , tt10, tt11, tt12, tt13, tt14, tt15, tt16,
84 tt17, tt18, tt19, tt20, tt21, tt22, tt23, tt24,
85 tt25, tt26, tt27, tt28, tt29, tt30, tt31, tt32, *y;
87 /* We unrolled the loops */
88 /* Odd-even ordering is integrated before the 1st stage */
89 t17 = c17 * (x[0] - x[31]);
91 t18 = c18 * (x[2] - x[29]);
93 t19 = c19 * (x[4] - x[27]);
95 t20 = c20 * (x[6] - x[25]);
97 t21 = c21 * (x[8] - x[23]);
99 t22 = c22 * (x[10] - x[21]);
101 t23 = c23 * (x[12] - x[19]);
103 t24 = c24 * (x[14] - x[17]);
105 t25 = c25 * (x[16] - x[15]);
107 t26 = c26 * (x[18] - x[13]);
109 t27 = c27 * (x[20] - x[11]);
111 t28 = c28 * (x[22] - x[9]);
113 t29 = c29 * (x[24] - x[7]);
115 t30 = c30 * (x[26] - x[5]);
117 t31 = c31 * (x[28] - x[3]);
119 t32 = c32 * (x[30] - x[1]);
122 tt9 = c9 * (t1 - t9 );
124 tt10 = c10 * (t2 - t10);
126 tt11 = c11 * (t3 - t11);
128 tt12 = c12 * (t4 - t12);
130 tt13 = c13 * (t5 - t13);
132 tt14 = c14 * (t6 - t14);
134 tt15 = c15 * (t7 - t15);
136 tt16 = c16 * (t8 - t16);
138 tt25 = c9 * (t17 - t25);
140 tt26 = c10 * (t18 - t26);
142 tt27 = c11 * (t19 - t27);
144 tt28 = c12 * (t20 - t28);
146 tt29 = c13 * (t21 - t29);
148 tt30 = c14 * (t22 - t30);
150 tt31 = c15 * (t23 - t31);
152 tt32 = c16 * (t24 - t32);
155 t5 = c5 * (tt1 - tt5 );
157 t6 = c6 * (tt2 - tt6 );
159 t7 = c7 * (tt3 - tt7 );
161 t8 = c8 * (tt4 - tt8 );
163 t13 = c5 * (tt9 - tt13);
165 t14 = c6 * (tt10 - tt14);
167 t15 = c7 * (tt11 - tt15);
169 t16 = c8 * (tt12 - tt16);
171 t21 = c5 * (tt17 - tt21);
173 t22 = c6 * (tt18 - tt22);
175 t23 = c7 * (tt19 - tt23);
177 t24 = c8 * (tt20 - tt24);
179 t29 = c5 * (tt25 - tt29);
181 t30 = c6 * (tt26 - tt30);
183 t31 = c7 * (tt27 - tt31);
185 t32 = c8 * (tt28 - tt32);
188 tt3 = c3 * (t1 - t3 );
190 tt4 = c4 * (t2 - t4 );
192 tt7 = c3 * (t5 - t7 );
194 tt8 = c4 * (t6 - t8 );
196 tt11 = c3 * (t9 - t11);
198 tt12 = c4 * (t10 - t12);
200 tt15 = c3 * (t13 - t15);
202 tt16 = c4 * (t14 - t16);
204 tt19 = c3 * (t17 - t19);
206 tt20 = c4 * (t18 - t20);
208 tt23 = c3 * (t21 - t23);
210 tt24 = c4 * (t22 - t24);
212 tt27 = c3 * (t25 - t27);
214 tt28 = c4 * (t26 - t28);
216 tt31 = c3 * (t29 - t31);
218 tt32 = c4 * (t30 - t32);
220 /* Bit-reverse ordering is integrated after the 5th stage */
221 /* Begin to split the result of the DCT (t1 to t32) in the filter bank */
222 x = b->actual + b->pos;
223 y = (b->actual == b->v1 ? b->v2 : b->v1) + b->pos;
224 x[0] = -(y[0] = c2 * (tt1 - tt2 )); /* t17 */
225 x[256] = 0; y[256] = tt1 + tt2; /* t1 */
226 t25 = c2 * (tt3 - tt4 );
228 t21 = c2 * (tt5 - tt6 );
230 t29 = c2 * (tt7 - tt8 );
232 t19 = c2 * (tt9 - tt10);
234 t27 = c2 * (tt11 - tt12);
236 t23 = c2 * (tt13 - tt14);
238 t31 = c2 * (tt15 - tt16);
240 t18 = c2 * (tt17 - tt18);
242 t26 = c2 * (tt19 - tt20);
244 t22 = c2 * (tt21 - tt22);
246 t30 = c2 * (tt23 - tt24);
248 t20 = c2 * (tt25 - tt26);
250 t28 = c2 * (tt27 - tt28);
252 t24 = c2 * (tt29 - tt30);
254 t32 = c2 * (tt31 - tt32);
257 /* Keep on splitting the result */
258 y[384] = y[128] = t9 - (x[128] = -(x[384] = t25)); /* t25, t9 */
266 y[320] = y[192] = t5 + t13; /* t5 */
267 y[448] = y[64] = t13 + t21; /* t13 */
268 x[64] = -(x[448] = t21 - (x[192] = -(x[320] = t29))); /* t29, t21 */
278 y[288] = y[224] = t3 + t7; /* t3 */
279 y[352] = y[160] = t7 + t11; /* t7 */
280 y[416] = y[96] = t11 + t15; /* t11 */
281 y[480] = y[32] = t15 + t19; /* t15 */
282 x[32] = -(x[480] = t19 + t23); /* t19 */
283 x[96] = -(x[416] = t23 + t27); /* t23 */
284 x[160] = -(x[352] = t27 - (x[224] = -(x[288] = t31))); /* t31, t27 */
292 y[272] = y[240] = t2 + t4; /* t2 */
293 y[304] = y[208] = t4 + t6; /* t4 */
294 y[336] = y[176] = t6 + t8; /* t6 */
295 y[368] = y[144] = t8 + t10; /* t8 */
296 y[400] = y[112] = t10 + t12; /* t10 */
297 y[432] = y[80] = t12 + t14; /* t12 */
298 y[464] = y[48] = t14 + t16; /* t14 */
299 y[496] = y[16] = t16 + t18; /* t16 */
300 x[16] = -(x[496] = t18 + t20); /* t18 */
301 x[48] = -(x[464] = t20 + t22); /* t20 */
302 x[80] = -(x[432] = t22 + t24); /* t22 */
303 x[112] = -(x[400] = t24 + t26); /* t24 */
304 x[144] = -(x[368] = t26 + t28); /* t26 */
305 x[176] = -(x[336] = t28 + t30); /* t28 */
306 x[208] = -(x[304] = t30 - (x[240] = -(x[272] = t32))); /* t32, t30 */
307 /* Note that to be really complete, the DCT should multiply t1 by sqrt(2)/N
308 and t2 to t32 by 2/N, and would take 321 additions and multiplications.
309 But that's unuseful in this application. */
313 /*****************************************************************************
314 * PCM: Pulse Code Modulation
315 *****************************************************************************
316 * Compute 32 PCM samples with a convolution product
317 *****************************************************************************/
319 void PCM(adec_bank_t *b, s16 **pcm, int jump)
323 /* These values are not in the same order as in Annex 3-B.3 of the ISO/IEC
325 static const float c[512] = {
326 0.000000000 * F, -0.000442505 * F, 0.003250122 * F, -0.007003784 * F,
327 0.031082153 * F, -0.078628540 * F, 0.100311279 * F, -0.572036743 * F,
328 1.144989014 * F, 0.572036743 * F, 0.100311279 * F, 0.078628540 * F,
329 0.031082153 * F, 0.007003784 * F, 0.003250122 * F, 0.000442505 * F,
330 -0.000015259 * F, -0.000473022 * F, 0.003326416 * F, -0.007919312 * F,
331 0.030517578 * F, -0.084182739 * F, 0.090927124 * F, -0.600219727 * F,
332 1.144287109 * F, 0.543823242 * F, 0.108856201 * F, 0.073059082 * F,
333 0.031478882 * F, 0.006118774 * F, 0.003173828 * F, 0.000396729 * F,
334 -0.000015259 * F, -0.000534058 * F, 0.003387451 * F, -0.008865356 * F,
335 0.029785156 * F, -0.089706421 * F, 0.080688477 * F, -0.628295898 * F,
336 1.142211914 * F, 0.515609741 * F, 0.116577148 * F, 0.067520142 * F,
337 0.031738281 * F, 0.005294800 * F, 0.003082275 * F, 0.000366211 * F,
338 -0.000015259 * F, -0.000579834 * F, 0.003433228 * F, -0.009841919 * F,
339 0.028884888 * F, -0.095169067 * F, 0.069595337 * F, -0.656219482 * F,
340 1.138763428 * F, 0.487472534 * F, 0.123474121 * F, 0.061996460 * F,
341 0.031845093 * F, 0.004486084 * F, 0.002990723 * F, 0.000320435 * F,
342 -0.000015259 * F, -0.000625610 * F, 0.003463745 * F, -0.010848999 * F,
343 0.027801514 * F, -0.100540161 * F, 0.057617188 * F, -0.683914185 * F,
344 1.133926392 * F, 0.459472656 * F, 0.129577637 * F, 0.056533813 * F,
345 0.031814575 * F, 0.003723145 * F, 0.002899170 * F, 0.000289917 * F,
346 -0.000015259 * F, -0.000686646 * F, 0.003479004 * F, -0.011886597 * F,
347 0.026535034 * F, -0.105819702 * F, 0.044784546 * F, -0.711318970 * F,
348 1.127746582 * F, 0.431655884 * F, 0.134887695 * F, 0.051132202 * F,
349 0.031661987 * F, 0.003005981 * F, 0.002792358 * F, 0.000259399 * F,
350 -0.000015259 * F, -0.000747681 * F, 0.003479004 * F, -0.012939453 * F,
351 0.025085449 * F, -0.110946655 * F, 0.031082153 * F, -0.738372803 * F,
352 1.120223999 * F, 0.404083252 * F, 0.139450073 * F, 0.045837402 * F,
353 0.031387329 * F, 0.002334595 * F, 0.002685547 * F, 0.000244141 * F,
354 -0.000030518 * F, -0.000808716 * F, 0.003463745 * F, -0.014022827 * F,
355 0.023422241 * F, -0.115921021 * F, 0.016510010 * F, -0.765029907 * F,
356 1.111373901 * F, 0.376800537 * F, 0.143264771 * F, 0.040634155 * F,
357 0.031005859 * F, 0.001693726 * F, 0.002578735 * F, 0.000213623 * F,
358 -0.000030518 * F, -0.000885010 * F, 0.003417969 * F, -0.015121460 * F,
359 0.021575928 * F, -0.120697021 * F, 0.001068115 * F, -0.791213989 * F,
360 1.101211548 * F, 0.349868774 * F, 0.146362305 * F, 0.035552979 * F,
361 0.030532837 * F, 0.001098633 * F, 0.002456665 * F, 0.000198364 * F,
362 -0.000030518 * F, -0.000961304 * F, 0.003372192 * F, -0.016235352 * F,
363 0.019531250 * F, -0.125259399 * F, -0.015228271 * F, -0.816864014 * F,
364 1.089782715 * F, 0.323318481 * F, 0.148773193 * F, 0.030609131 * F,
365 0.029937744 * F, 0.000549316 * F, 0.002349854 * F, 0.000167847 * F,
366 -0.000030518 * F, -0.001037598 * F, 0.003280640 * F, -0.017349243 * F,
367 0.017257690 * F, -0.129562378 * F, -0.032379150 * F, -0.841949463 * F,
368 1.077117920 * F, 0.297210693 * F, 0.150497437 * F, 0.025817871 * F,
369 0.029281616 * F, 0.000030518 * F, 0.002243042 * F, 0.000152588 * F,
370 -0.000045776 * F, -0.001113892 * F, 0.003173828 * F, -0.018463135 * F,
371 0.014801025 * F, -0.133590698 * F, -0.050354004 * F, -0.866363525 * F,
372 1.063217163 * F, 0.271591187 * F, 0.151596069 * F, 0.021179199 * F,
373 0.028533936 * F, -0.000442505 * F, 0.002120972 * F, 0.000137329 * F,
374 -0.000045776 * F, -0.001205444 * F, 0.003051758 * F, -0.019577026 * F,
375 0.012115479 * F, -0.137298584 * F, -0.069168091 * F, -0.890090942 * F,
376 1.048156738 * F, 0.246505737 * F, 0.152069092 * F, 0.016708374 * F,
377 0.027725220 * F, -0.000869751 * F, 0.002014160 * F, 0.000122070 * F,
378 -0.000061035 * F, -0.001296997 * F, 0.002883911 * F, -0.020690918 * F,
379 0.009231567 * F, -0.140670776 * F, -0.088775635 * F, -0.913055420 * F,
380 1.031936646 * F, 0.221984863 * F, 0.151962280 * F, 0.012420654 * F,
381 0.026840210 * F, -0.001266479 * F, 0.001907349 * F, 0.000106812 * F,
382 -0.000061035 * F, -0.001388550 * F, 0.002700806 * F, -0.021789551 * F,
383 0.006134033 * F, -0.143676758 * F, -0.109161377 * F, -0.935195923 * F,
384 1.014617920 * F, 0.198059082 * F, 0.151306152 * F, 0.008316040 * F,
385 0.025909424 * F, -0.001617432 * F, 0.001785278 * F, 0.000106812 * F,
386 -0.000076294 * F, -0.001480103 * F, 0.002487183 * F, -0.022857666 * F,
387 0.002822876 * F, -0.146255493 * F, -0.130310059 * F, -0.956481934 * F,
388 0.996246338 * F, 0.174789429 * F, 0.150115967 * F, 0.004394531 * F,
389 0.024932861 * F, -0.001937866 * F, 0.001693726 * F, 0.000091553 * F,
390 -0.000076294 * F, -0.001586914 * F, 0.002227783 * F, -0.023910522 * F,
391 -0.000686646 * F, -0.148422241 * F, -0.152206421 * F, -0.976852417 * F,
392 0.976852417 * F, 0.152206421 * F, 0.148422241 * F, 0.000686646 * F,
393 0.023910522 * F, -0.002227783 * F, 0.001586914 * F, 0.000076294 * F,
394 -0.000091553 * F, -0.001693726 * F, 0.001937866 * F, -0.024932861 * F,
395 -0.004394531 * F, -0.150115967 * F, -0.174789429 * F, -0.996246338 * F,
396 0.956481934 * F, 0.130310059 * F, 0.146255493 * F, -0.002822876 * F,
397 0.022857666 * F, -0.002487183 * F, 0.001480103 * F, 0.000076294 * F,
398 -0.000106812 * F, -0.001785278 * F, 0.001617432 * F, -0.025909424 * F,
399 -0.008316040 * F, -0.151306152 * F, -0.198059082 * F, -1.014617920 * F,
400 0.935195923 * F, 0.109161377 * F, 0.143676758 * F, -0.006134033 * F,
401 0.021789551 * F, -0.002700806 * F, 0.001388550 * F, 0.000061035 * F,
402 -0.000106812 * F, -0.001907349 * F, 0.001266479 * F, -0.026840210 * F,
403 -0.012420654 * F, -0.151962280 * F, -0.221984863 * F, -1.031936646 * F,
404 0.913055420 * F, 0.088775635 * F, 0.140670776 * F, -0.009231567 * F,
405 0.020690918 * F, -0.002883911 * F, 0.001296997 * F, 0.000061035 * F,
406 -0.000122070 * F, -0.002014160 * F, 0.000869751 * F, -0.027725220 * F,
407 -0.016708374 * F, -0.152069092 * F, -0.246505737 * F, -1.048156738 * F,
408 0.890090942 * F, 0.069168091 * F, 0.137298584 * F, -0.012115479 * F,
409 0.019577026 * F, -0.003051758 * F, 0.001205444 * F, 0.000045776 * F,
410 -0.000137329 * F, -0.002120972 * F, 0.000442505 * F, -0.028533936 * F,
411 -0.021179199 * F, -0.151596069 * F, -0.271591187 * F, -1.063217163 * F,
412 0.866363525 * F, 0.050354004 * F, 0.133590698 * F, -0.014801025 * F,
413 0.018463135 * F, -0.003173828 * F, 0.001113892 * F, 0.000045776 * F,
414 -0.000152588 * F, -0.002243042 * F, -0.000030518 * F, -0.029281616 * F,
415 -0.025817871 * F, -0.150497437 * F, -0.297210693 * F, -1.077117920 * F,
416 0.841949463 * F, 0.032379150 * F, 0.129562378 * F, -0.017257690 * F,
417 0.017349243 * F, -0.003280640 * F, 0.001037598 * F, 0.000030518 * F,
418 -0.000167847 * F, -0.002349854 * F, -0.000549316 * F, -0.029937744 * F,
419 -0.030609131 * F, -0.148773193 * F, -0.323318481 * F, -1.089782715 * F,
420 0.816864014 * F, 0.015228271 * F, 0.125259399 * F, -0.019531250 * F,
421 0.016235352 * F, -0.003372192 * F, 0.000961304 * F, 0.000030518 * F,
422 -0.000198364 * F, -0.002456665 * F, -0.001098633 * F, -0.030532837 * F,
423 -0.035552979 * F, -0.146362305 * F, -0.349868774 * F, -1.101211548 * F,
424 0.791213989 * F, -0.001068115 * F, 0.120697021 * F, -0.021575928 * F,
425 0.015121460 * F, -0.003417969 * F, 0.000885010 * F, 0.000030518 * F,
426 -0.000213623 * F, -0.002578735 * F, -0.001693726 * F, -0.031005859 * F,
427 -0.040634155 * F, -0.143264771 * F, -0.376800537 * F, -1.111373901 * F,
428 0.765029907 * F, -0.016510010 * F, 0.115921021 * F, -0.023422241 * F,
429 0.014022827 * F, -0.003463745 * F, 0.000808716 * F, 0.000030518 * F,
430 -0.000244141 * F, -0.002685547 * F, -0.002334595 * F, -0.031387329 * F,
431 -0.045837402 * F, -0.139450073 * F, -0.404083252 * F, -1.120223999 * F,
432 0.738372803 * F, -0.031082153 * F, 0.110946655 * F, -0.025085449 * F,
433 0.012939453 * F, -0.003479004 * F, 0.000747681 * F, 0.000015259 * F,
434 -0.000259399 * F, -0.002792358 * F, -0.003005981 * F, -0.031661987 * F,
435 -0.051132202 * F, -0.134887695 * F, -0.431655884 * F, -1.127746582 * F,
436 0.711318970 * F, -0.044784546 * F, 0.105819702 * F, -0.026535034 * F,
437 0.011886597 * F, -0.003479004 * F, 0.000686646 * F, 0.000015259 * F,
438 -0.000289917 * F, -0.002899170 * F, -0.003723145 * F, -0.031814575 * F,
439 -0.056533813 * F, -0.129577637 * F, -0.459472656 * F, -1.133926392 * F,
440 0.683914185 * F, -0.057617188 * F, 0.100540161 * F, -0.027801514 * F,
441 0.010848999 * F, -0.003463745 * F, 0.000625610 * F, 0.000015259 * F,
442 -0.000320435 * F, -0.002990723 * F, -0.004486084 * F, -0.031845093 * F,
443 -0.061996460 * F, -0.123474121 * F, -0.487472534 * F, -1.138763428 * F,
444 0.656219482 * F, -0.069595337 * F, 0.095169067 * F, -0.028884888 * F,
445 0.009841919 * F, -0.003433228 * F, 0.000579834 * F, 0.000015259 * F,
446 -0.000366211 * F, -0.003082275 * F, -0.005294800 * F, -0.031738281 * F,
447 -0.067520142 * F, -0.116577148 * F, -0.515609741 * F, -1.142211914 * F,
448 0.628295898 * F, -0.080688477 * F, 0.089706421 * F, -0.029785156 * F,
449 0.008865356 * F, -0.003387451 * F, 0.000534058 * F, 0.000015259 * F,
450 -0.000396729 * F, -0.003173828 * F, -0.006118774 * F, -0.031478882 * F,
451 -0.073059082 * F, -0.108856201 * F, -0.543823242 * F, -1.144287109 * F,
452 0.600219727 * F, -0.090927124 * F, 0.084182739 * F, -0.030517578 * F,
453 0.007919312 * F, -0.003326416 * F, 0.000473022 * F, 0.000015259 * F
465 for(i=0; i<32; i++) {
482 if((tmp += *f++ * *v) > 32767)
483 /* ceiling saturation */
487 /* floor saturation */
497 for(i=0; i<32; i++) {
514 if((tmp += *f++ * *v) > 32767)
527 for(i=0; i<32; i++) {
544 if((tmp += *f++ * *v) > 32767)
557 for(i=0; i<32; i++) {
574 if((tmp += *f++ * *v) > 32767)
587 for(i=0; i<32; i++) {
604 if((tmp += *f++ * *v) > 32767)
617 for(i=0; i<32; i++) {
634 if((tmp += *f++ * *v) > 32767)
647 for(i=0; i<32; i++) {
664 if((tmp += *f++ * *v) > 32767)
677 for(i=0; i<32; i++) {
694 if((tmp += *f++ * *v) > 32767)
707 for(i=0; i<32; i++) {
724 if((tmp += *f++ * *v) > 32767)
737 for(i=0; i<32; i++) {
754 if((tmp += *f++ * *v) > 32767)
767 for(i=0; i<32; i++) {
784 if((tmp += *f++ * *v) > 32767)
797 for(i=0; i<32; i++) {
814 if((tmp += *f++ * *v) > 32767)
827 for(i=0; i<32; i++) {
844 if((tmp += *f++ * *v) > 32767)
857 for(i=0; i<32; i++) {
874 if((tmp += *f++ * *v) > 32767)
887 for(i=0; i<32; i++) {
904 if((tmp += *f++ * *v) > 32767)
917 for(i=0; i<32; i++) {
933 if((tmp += *f++ * *v) > 32767)
946 /* Set the next position in the filter bank */
949 b->actual = (b->actual == b->v1 ? b->v2 : b->v1);