1 /*
2 * libmad - MPEG audio decoder library
3 * Copyright (C) 2000-2004 Underbit Technologies, Inc.
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
18 *
19 * $Id: synth.c,v 1.25 2004/01/23 09:41:33 rob Exp $
20 */
21
22 # ifdef HAVE_CONFIG_H
23 # include "config.h"
24 # endif
25
26 # include "global.h"
27
28 # include "fixed.h"
29 # include "frame.h"
30 # include "synth.h"
31
32 /*
33 * NAME: synth->init()
34 * DESCRIPTION: initialize synth struct
35 */
mad_synth_init(struct mad_synth * synth)36 void mad_synth_init(struct mad_synth *synth)
37 {
38 mad_synth_mute(synth);
39
40 synth->phase = 0;
41
42 synth->pcm.samplerate = 0;
43 synth->pcm.channels = 0;
44 synth->pcm.length = 0;
45 }
46
47 /*
48 * NAME: synth->mute()
49 * DESCRIPTION: zero all polyphase filterbank values, resetting synthesis
50 */
mad_synth_mute(struct mad_synth * synth)51 void mad_synth_mute(struct mad_synth *synth)
52 {
53 unsigned int ch, s, v;
54
55 for (ch = 0; ch < 2; ++ch) {
56 for (s = 0; s < 16; ++s) {
57 for (v = 0; v < 8; ++v) {
58 synth->filter[ch][0][0][s][v] = synth->filter[ch][0][1][s][v] =
59 synth->filter[ch][1][0][s][v] = synth->filter[ch][1][1][s][v] = 0;
60 }
61 }
62 }
63 }
64
65 /*
66 * An optional optimization called here the Subband Synthesis Optimization
67 * (SSO) improves the performance of subband synthesis at the expense of
68 * accuracy.
69 *
70 * The idea is to simplify 32x32->64-bit multiplication to 32x32->32 such
71 * that extra scaling and rounding are not necessary. This often allows the
72 * compiler to use faster 32-bit multiply-accumulate instructions instead of
73 * explicit 64-bit multiply, shift, and add instructions.
74 *
75 * SSO works like this: a full 32x32->64-bit multiply of two mad_fixed_t
76 * values requires the result to be right-shifted 28 bits to be properly
77 * scaled to the same fixed-point format. Right shifts can be applied at any
78 * time to either operand or to the result, so the optimization involves
79 * careful placement of these shifts to minimize the loss of accuracy.
80 *
81 * First, a 14-bit shift is applied with rounding at compile-time to the D[]
82 * table of coefficients for the subband synthesis window. This only loses 2
83 * bits of accuracy because the lower 12 bits are always zero. A second
84 * 12-bit shift occurs after the DCT calculation. This loses 12 bits of
85 * accuracy. Finally, a third 2-bit shift occurs just before the sample is
86 * saved in the PCM buffer. 14 + 12 + 2 == 28 bits.
87 */
88
89 /* FPM_DEFAULT without OPT_SSO will actually lose accuracy and performance */
90
91 # if defined(FPM_DEFAULT) && !defined(OPT_SSO)
92 # define OPT_SSO
93 # endif
94
95 /* second SSO shift, with rounding */
96
97 # if defined(OPT_SSO)
98 # define SHIFT(x) (((x) + (1L << 11)) >> 12)
99 # else
100 # define SHIFT(x) (x)
101 # endif
102
103 /* possible DCT speed optimization */
104
105 # if defined(OPT_SPEED) && defined(MAD_F_MLX)
106 # define OPT_DCTO
107 # define MUL(x, y) \
108 ({ mad_fixed64hi_t hi; \
109 mad_fixed64lo_t lo; \
110 MAD_F_MLX(hi, lo, (x), (y)); \
111 hi << (32 - MAD_F_SCALEBITS - 3); \
112 })
113 # else
114 # undef OPT_DCTO
115 # define MUL(x, y) mad_f_mul((x), (y))
116 # endif
117
118 /*
119 * NAME: dct32()
120 * DESCRIPTION: perform fast in[32]->out[32] DCT
121 */
122 static
dct32(mad_fixed_t const in[32],unsigned int slot,mad_fixed_t lo[16][8],mad_fixed_t hi[16][8])123 void dct32(mad_fixed_t const in[32], unsigned int slot,
124 mad_fixed_t lo[16][8], mad_fixed_t hi[16][8])
125 {
126 mad_fixed_t t0, t1, t2, t3, t4, t5, t6, t7;
127 mad_fixed_t t8, t9, t10, t11, t12, t13, t14, t15;
128 mad_fixed_t t16, t17, t18, t19, t20, t21, t22, t23;
129 mad_fixed_t t24, t25, t26, t27, t28, t29, t30, t31;
130 mad_fixed_t t32, t33, t34, t35, t36, t37, t38, t39;
131 mad_fixed_t t40, t41, t42, t43, t44, t45, t46, t47;
132 mad_fixed_t t48, t49, t50, t51, t52, t53, t54, t55;
133 mad_fixed_t t56, t57, t58, t59, t60, t61, t62, t63;
134 mad_fixed_t t64, t65, t66, t67, t68, t69, t70, t71;
135 mad_fixed_t t72, t73, t74, t75, t76, t77, t78, t79;
136 mad_fixed_t t80, t81, t82, t83, t84, t85, t86, t87;
137 mad_fixed_t t88, t89, t90, t91, t92, t93, t94, t95;
138 mad_fixed_t t96, t97, t98, t99, t100, t101, t102, t103;
139 mad_fixed_t t104, t105, t106, t107, t108, t109, t110, t111;
140 mad_fixed_t t112, t113, t114, t115, t116, t117, t118, t119;
141 mad_fixed_t t120, t121, t122, t123, t124, t125, t126, t127;
142 mad_fixed_t t128, t129, t130, t131, t132, t133, t134, t135;
143 mad_fixed_t t136, t137, t138, t139, t140, t141, t142, t143;
144 mad_fixed_t t144, t145, t146, t147, t148, t149, t150, t151;
145 mad_fixed_t t152, t153, t154, t155, t156, t157, t158, t159;
146 mad_fixed_t t160, t161, t162, t163, t164, t165, t166, t167;
147 mad_fixed_t t168, t169, t170, t171, t172, t173, t174, t175;
148 mad_fixed_t t176;
149
150 /* costab[i] = cos(PI / (2 * 32) * i) */
151
152 # if defined(OPT_DCTO)
153 # define costab1 MAD_F(0x7fd8878e)
154 # define costab2 MAD_F(0x7f62368f)
155 # define costab3 MAD_F(0x7e9d55fc)
156 # define costab4 MAD_F(0x7d8a5f40)
157 # define costab5 MAD_F(0x7c29fbee)
158 # define costab6 MAD_F(0x7a7d055b)
159 # define costab7 MAD_F(0x78848414)
160 # define costab8 MAD_F(0x7641af3d)
161 # define costab9 MAD_F(0x73b5ebd1)
162 # define costab10 MAD_F(0x70e2cbc6)
163 # define costab11 MAD_F(0x6dca0d14)
164 # define costab12 MAD_F(0x6a6d98a4)
165 # define costab13 MAD_F(0x66cf8120)
166 # define costab14 MAD_F(0x62f201ac)
167 # define costab15 MAD_F(0x5ed77c8a)
168 # define costab16 MAD_F(0x5a82799a)
169 # define costab17 MAD_F(0x55f5a4d2)
170 # define costab18 MAD_F(0x5133cc94)
171 # define costab19 MAD_F(0x4c3fdff4)
172 # define costab20 MAD_F(0x471cece7)
173 # define costab21 MAD_F(0x41ce1e65)
174 # define costab22 MAD_F(0x3c56ba70)
175 # define costab23 MAD_F(0x36ba2014)
176 # define costab24 MAD_F(0x30fbc54d)
177 # define costab25 MAD_F(0x2b1f34eb)
178 # define costab26 MAD_F(0x25280c5e)
179 # define costab27 MAD_F(0x1f19f97b)
180 # define costab28 MAD_F(0x18f8b83c)
181 # define costab29 MAD_F(0x12c8106f)
182 # define costab30 MAD_F(0x0c8bd35e)
183 # define costab31 MAD_F(0x0647d97c)
184 # else
185 # define costab1 MAD_F(0x0ffb10f2) /* 0.998795456 */
186 # define costab2 MAD_F(0x0fec46d2) /* 0.995184727 */
187 # define costab3 MAD_F(0x0fd3aac0) /* 0.989176510 */
188 # define costab4 MAD_F(0x0fb14be8) /* 0.980785280 */
189 # define costab5 MAD_F(0x0f853f7e) /* 0.970031253 */
190 # define costab6 MAD_F(0x0f4fa0ab) /* 0.956940336 */
191 # define costab7 MAD_F(0x0f109082) /* 0.941544065 */
192 # define costab8 MAD_F(0x0ec835e8) /* 0.923879533 */
193 # define costab9 MAD_F(0x0e76bd7a) /* 0.903989293 */
194 # define costab10 MAD_F(0x0e1c5979) /* 0.881921264 */
195 # define costab11 MAD_F(0x0db941a3) /* 0.857728610 */
196 # define costab12 MAD_F(0x0d4db315) /* 0.831469612 */
197 # define costab13 MAD_F(0x0cd9f024) /* 0.803207531 */
198 # define costab14 MAD_F(0x0c5e4036) /* 0.773010453 */
199 # define costab15 MAD_F(0x0bdaef91) /* 0.740951125 */
200 # define costab16 MAD_F(0x0b504f33) /* 0.707106781 */
201 # define costab17 MAD_F(0x0abeb49a) /* 0.671558955 */
202 # define costab18 MAD_F(0x0a267993) /* 0.634393284 */
203 # define costab19 MAD_F(0x0987fbfe) /* 0.595699304 */
204 # define costab20 MAD_F(0x08e39d9d) /* 0.555570233 */
205 # define costab21 MAD_F(0x0839c3cd) /* 0.514102744 */
206 # define costab22 MAD_F(0x078ad74e) /* 0.471396737 */
207 # define costab23 MAD_F(0x06d74402) /* 0.427555093 */
208 # define costab24 MAD_F(0x061f78aa) /* 0.382683432 */
209 # define costab25 MAD_F(0x0563e69d) /* 0.336889853 */
210 # define costab26 MAD_F(0x04a5018c) /* 0.290284677 */
211 # define costab27 MAD_F(0x03e33f2f) /* 0.242980180 */
212 # define costab28 MAD_F(0x031f1708) /* 0.195090322 */
213 # define costab29 MAD_F(0x0259020e) /* 0.146730474 */
214 # define costab30 MAD_F(0x01917a6c) /* 0.098017140 */
215 # define costab31 MAD_F(0x00c8fb30) /* 0.049067674 */
216 # endif
217
218 t0 = in[0] + in[31]; t16 = MUL(in[0] - in[31], costab1);
219 t1 = in[15] + in[16]; t17 = MUL(in[15] - in[16], costab31);
220
221 t41 = t16 + t17;
222 t59 = MUL(t16 - t17, costab2);
223 t33 = t0 + t1;
224 t50 = MUL(t0 - t1, costab2);
225
226 t2 = in[7] + in[24]; t18 = MUL(in[7] - in[24], costab15);
227 t3 = in[8] + in[23]; t19 = MUL(in[8] - in[23], costab17);
228
229 t42 = t18 + t19;
230 t60 = MUL(t18 - t19, costab30);
231 t34 = t2 + t3;
232 t51 = MUL(t2 - t3, costab30);
233
234 t4 = in[3] + in[28]; t20 = MUL(in[3] - in[28], costab7);
235 t5 = in[12] + in[19]; t21 = MUL(in[12] - in[19], costab25);
236
237 t43 = t20 + t21;
238 t61 = MUL(t20 - t21, costab14);
239 t35 = t4 + t5;
240 t52 = MUL(t4 - t5, costab14);
241
242 t6 = in[4] + in[27]; t22 = MUL(in[4] - in[27], costab9);
243 t7 = in[11] + in[20]; t23 = MUL(in[11] - in[20], costab23);
244
245 t44 = t22 + t23;
246 t62 = MUL(t22 - t23, costab18);
247 t36 = t6 + t7;
248 t53 = MUL(t6 - t7, costab18);
249
250 t8 = in[1] + in[30]; t24 = MUL(in[1] - in[30], costab3);
251 t9 = in[14] + in[17]; t25 = MUL(in[14] - in[17], costab29);
252
253 t45 = t24 + t25;
254 t63 = MUL(t24 - t25, costab6);
255 t37 = t8 + t9;
256 t54 = MUL(t8 - t9, costab6);
257
258 t10 = in[6] + in[25]; t26 = MUL(in[6] - in[25], costab13);
259 t11 = in[9] + in[22]; t27 = MUL(in[9] - in[22], costab19);
260
261 t46 = t26 + t27;
262 t64 = MUL(t26 - t27, costab26);
263 t38 = t10 + t11;
264 t55 = MUL(t10 - t11, costab26);
265
266 t12 = in[2] + in[29]; t28 = MUL(in[2] - in[29], costab5);
267 t13 = in[13] + in[18]; t29 = MUL(in[13] - in[18], costab27);
268
269 t47 = t28 + t29;
270 t65 = MUL(t28 - t29, costab10);
271 t39 = t12 + t13;
272 t56 = MUL(t12 - t13, costab10);
273
274 t14 = in[5] + in[26]; t30 = MUL(in[5] - in[26], costab11);
275 t15 = in[10] + in[21]; t31 = MUL(in[10] - in[21], costab21);
276
277 t48 = t30 + t31;
278 t66 = MUL(t30 - t31, costab22);
279 t40 = t14 + t15;
280 t57 = MUL(t14 - t15, costab22);
281
282 t69 = t33 + t34; t89 = MUL(t33 - t34, costab4);
283 t70 = t35 + t36; t90 = MUL(t35 - t36, costab28);
284 t71 = t37 + t38; t91 = MUL(t37 - t38, costab12);
285 t72 = t39 + t40; t92 = MUL(t39 - t40, costab20);
286 t73 = t41 + t42; t94 = MUL(t41 - t42, costab4);
287 t74 = t43 + t44; t95 = MUL(t43 - t44, costab28);
288 t75 = t45 + t46; t96 = MUL(t45 - t46, costab12);
289 t76 = t47 + t48; t97 = MUL(t47 - t48, costab20);
290
291 t78 = t50 + t51; t100 = MUL(t50 - t51, costab4);
292 t79 = t52 + t53; t101 = MUL(t52 - t53, costab28);
293 t80 = t54 + t55; t102 = MUL(t54 - t55, costab12);
294 t81 = t56 + t57; t103 = MUL(t56 - t57, costab20);
295
296 t83 = t59 + t60; t106 = MUL(t59 - t60, costab4);
297 t84 = t61 + t62; t107 = MUL(t61 - t62, costab28);
298 t85 = t63 + t64; t108 = MUL(t63 - t64, costab12);
299 t86 = t65 + t66; t109 = MUL(t65 - t66, costab20);
300
301 t113 = t69 + t70;
302 t114 = t71 + t72;
303
304 /* 0 */ hi[15][slot] = SHIFT(t113 + t114);
305 /* 16 */ lo[ 0][slot] = SHIFT(MUL(t113 - t114, costab16));
306
307 t115 = t73 + t74;
308 t116 = t75 + t76;
309
310 t32 = t115 + t116;
311
312 /* 1 */ hi[14][slot] = SHIFT(t32);
313
314 t118 = t78 + t79;
315 t119 = t80 + t81;
316
317 t58 = t118 + t119;
318
319 /* 2 */ hi[13][slot] = SHIFT(t58);
320
321 t121 = t83 + t84;
322 t122 = t85 + t86;
323
324 t67 = t121 + t122;
325
326 t49 = (t67 * 2) - t32;
327
328 /* 3 */ hi[12][slot] = SHIFT(t49);
329
330 t125 = t89 + t90;
331 t126 = t91 + t92;
332
333 t93 = t125 + t126;
334
335 /* 4 */ hi[11][slot] = SHIFT(t93);
336
337 t128 = t94 + t95;
338 t129 = t96 + t97;
339
340 t98 = t128 + t129;
341
342 t68 = (t98 * 2) - t49;
343
344 /* 5 */ hi[10][slot] = SHIFT(t68);
345
346 t132 = t100 + t101;
347 t133 = t102 + t103;
348
349 t104 = t132 + t133;
350
351 t82 = (t104 * 2) - t58;
352
353 /* 6 */ hi[ 9][slot] = SHIFT(t82);
354
355 t136 = t106 + t107;
356 t137 = t108 + t109;
357
358 t110 = t136 + t137;
359
360 t87 = (t110 * 2) - t67;
361
362 t77 = (t87 * 2) - t68;
363
364 /* 7 */ hi[ 8][slot] = SHIFT(t77);
365
366 t141 = MUL(t69 - t70, costab8);
367 t142 = MUL(t71 - t72, costab24);
368 t143 = t141 + t142;
369
370 /* 8 */ hi[ 7][slot] = SHIFT(t143);
371 /* 24 */ lo[ 8][slot] =
372 SHIFT((MUL(t141 - t142, costab16) * 2) - t143);
373
374 t144 = MUL(t73 - t74, costab8);
375 t145 = MUL(t75 - t76, costab24);
376 t146 = t144 + t145;
377
378 t88 = (t146 * 2) - t77;
379
380 /* 9 */ hi[ 6][slot] = SHIFT(t88);
381
382 t148 = MUL(t78 - t79, costab8);
383 t149 = MUL(t80 - t81, costab24);
384 t150 = t148 + t149;
385
386 t105 = (t150 * 2) - t82;
387
388 /* 10 */ hi[ 5][slot] = SHIFT(t105);
389
390 t152 = MUL(t83 - t84, costab8);
391 t153 = MUL(t85 - t86, costab24);
392 t154 = t152 + t153;
393
394 t111 = (t154 * 2) - t87;
395
396 t99 = (t111 * 2) - t88;
397
398 /* 11 */ hi[ 4][slot] = SHIFT(t99);
399
400 t157 = MUL(t89 - t90, costab8);
401 t158 = MUL(t91 - t92, costab24);
402 t159 = t157 + t158;
403
404 t127 = (t159 * 2) - t93;
405
406 /* 12 */ hi[ 3][slot] = SHIFT(t127);
407
408 t160 = (MUL(t125 - t126, costab16) * 2) - t127;
409
410 /* 20 */ lo[ 4][slot] = SHIFT(t160);
411 /* 28 */ lo[12][slot] =
412 SHIFT((((MUL(t157 - t158, costab16) * 2) - t159) * 2) - t160);
413
414 t161 = MUL(t94 - t95, costab8);
415 t162 = MUL(t96 - t97, costab24);
416 t163 = t161 + t162;
417
418 t130 = (t163 * 2) - t98;
419
420 t112 = (t130 * 2) - t99;
421
422 /* 13 */ hi[ 2][slot] = SHIFT(t112);
423
424 t164 = (MUL(t128 - t129, costab16) * 2) - t130;
425
426 t166 = MUL(t100 - t101, costab8);
427 t167 = MUL(t102 - t103, costab24);
428 t168 = t166 + t167;
429
430 t134 = (t168 * 2) - t104;
431
432 t120 = (t134 * 2) - t105;
433
434 /* 14 */ hi[ 1][slot] = SHIFT(t120);
435
436 t135 = (MUL(t118 - t119, costab16) * 2) - t120;
437
438 /* 18 */ lo[ 2][slot] = SHIFT(t135);
439
440 t169 = (MUL(t132 - t133, costab16) * 2) - t134;
441
442 t151 = (t169 * 2) - t135;
443
444 /* 22 */ lo[ 6][slot] = SHIFT(t151);
445
446 t170 = (((MUL(t148 - t149, costab16) * 2) - t150) * 2) - t151;
447
448 /* 26 */ lo[10][slot] = SHIFT(t170);
449 /* 30 */ lo[14][slot] =
450 SHIFT((((((MUL(t166 - t167, costab16) * 2) -
451 t168) * 2) - t169) * 2) - t170);
452
453 t171 = MUL(t106 - t107, costab8);
454 t172 = MUL(t108 - t109, costab24);
455 t173 = t171 + t172;
456
457 t138 = (t173 * 2) - t110;
458
459 t123 = (t138 * 2) - t111;
460
461 t139 = (MUL(t121 - t122, costab16) * 2) - t123;
462
463 t117 = (t123 * 2) - t112;
464
465 /* 15 */ hi[ 0][slot] = SHIFT(t117);
466
467 t124 = (MUL(t115 - t116, costab16) * 2) - t117;
468
469 /* 17 */ lo[ 1][slot] = SHIFT(t124);
470
471 t131 = (t139 * 2) - t124;
472
473 /* 19 */ lo[ 3][slot] = SHIFT(t131);
474
475 t140 = (t164 * 2) - t131;
476
477 /* 21 */ lo[ 5][slot] = SHIFT(t140);
478
479 t174 = (MUL(t136 - t137, costab16) * 2) - t138;
480
481 t155 = (t174 * 2) - t139;
482
483 t147 = (t155 * 2) - t140;
484
485 /* 23 */ lo[ 7][slot] = SHIFT(t147);
486
487 t156 = (((MUL(t144 - t145, costab16) * 2) - t146) * 2) - t147;
488
489 /* 25 */ lo[ 9][slot] = SHIFT(t156);
490
491 t175 = (((MUL(t152 - t153, costab16) * 2) - t154) * 2) - t155;
492
493 t165 = (t175 * 2) - t156;
494
495 /* 27 */ lo[11][slot] = SHIFT(t165);
496
497 t176 = (((((MUL(t161 - t162, costab16) * 2) -
498 t163) * 2) - t164) * 2) - t165;
499
500 /* 29 */ lo[13][slot] = SHIFT(t176);
501 /* 31 */ lo[15][slot] =
502 SHIFT((((((((MUL(t171 - t172, costab16) * 2) -
503 t173) * 2) - t174) * 2) - t175) * 2) - t176);
504
505 /*
506 * Totals:
507 * 80 multiplies
508 * 80 additions
509 * 119 subtractions
510 * 49 shifts (not counting SSO)
511 */
512 }
513
514 # undef MUL
515 # undef SHIFT
516
517 /* third SSO shift and/or D[] optimization preshift */
518
519 # if defined(OPT_SSO)
520 # if MAD_F_FRACBITS != 28
521 # error "MAD_F_FRACBITS must be 28 to use OPT_SSO"
522 # endif
523 # define ML0(hi, lo, x, y) ((lo) = (x) * (y))
524 # define MLA(hi, lo, x, y) ((lo) += (x) * (y))
525 # define MLN(hi, lo) ((lo) = -(lo))
526 # define MLZ(hi, lo) ((void) (hi), (mad_fixed_t) (lo))
527 # define SHIFT(x) ((x) >> 2)
528 # define PRESHIFT(x) ((MAD_F(x) + (1L << 13)) >> 14)
529 # else
530 # define ML0(hi, lo, x, y) MAD_F_ML0((hi), (lo), (x), (y))
531 # define MLA(hi, lo, x, y) MAD_F_MLA((hi), (lo), (x), (y))
532 # define MLN(hi, lo) MAD_F_MLN((hi), (lo))
533 # define MLZ(hi, lo) MAD_F_MLZ((hi), (lo))
534 # define SHIFT(x) (x)
535 # if defined(MAD_F_SCALEBITS)
536 # undef MAD_F_SCALEBITS
537 # define MAD_F_SCALEBITS (MAD_F_FRACBITS - 12)
538 # define PRESHIFT(x) (MAD_F(x) >> 12)
539 # else
540 # define PRESHIFT(x) MAD_F(x)
541 # endif
542 # endif
543
544 static
545 mad_fixed_t const D[17][32] = {
546 # include "D.dat"
547 };
548
549 # if defined(ASO_SYNTH)
550 void synth_full(struct mad_synth *, struct mad_frame const *,
551 unsigned int, unsigned int);
552 # else
553 /*
554 * NAME: synth->full()
555 * DESCRIPTION: perform full frequency PCM synthesis
556 */
557 static
synth_full(struct mad_synth * synth,struct mad_frame const * frame,unsigned int nch,unsigned int ns)558 void synth_full(struct mad_synth *synth, struct mad_frame const *frame,
559 unsigned int nch, unsigned int ns)
560 {
561 unsigned int phase, ch, s, sb, pe, po;
562 mad_fixed_t *pcm1, *pcm2, (*filter)[2][2][16][8];
563 mad_fixed_t const (*sbsample)[36][32];
564 register mad_fixed_t (*fe)[8], (*fx)[8], (*fo)[8];
565 register mad_fixed_t const (*Dptr)[32], *ptr;
566 register mad_fixed64hi_t hi;
567 register mad_fixed64lo_t lo;
568
569 for (ch = 0; ch < nch; ++ch) {
570 sbsample = &frame->sbsample[ch];
571 filter = &synth->filter[ch];
572 phase = synth->phase;
573 pcm1 = synth->pcm.samples[ch];
574
575 for (s = 0; s < ns; ++s) {
576 dct32((*sbsample)[s], phase >> 1,
577 (*filter)[0][phase & 1], (*filter)[1][phase & 1]);
578
579 pe = phase & ~1;
580 po = ((phase - 1) & 0xf) | 1;
581
582 /* calculate 32 samples */
583
584 fe = &(*filter)[0][ phase & 1][0];
585 fx = &(*filter)[0][~phase & 1][0];
586 fo = &(*filter)[1][~phase & 1][0];
587
588 Dptr = &D[0];
589
590 ptr = *Dptr + po;
591 ML0(hi, lo, (*fx)[0], ptr[ 0]);
592 MLA(hi, lo, (*fx)[1], ptr[14]);
593 MLA(hi, lo, (*fx)[2], ptr[12]);
594 MLA(hi, lo, (*fx)[3], ptr[10]);
595 MLA(hi, lo, (*fx)[4], ptr[ 8]);
596 MLA(hi, lo, (*fx)[5], ptr[ 6]);
597 MLA(hi, lo, (*fx)[6], ptr[ 4]);
598 MLA(hi, lo, (*fx)[7], ptr[ 2]);
599 MLN(hi, lo);
600
601 ptr = *Dptr + pe;
602 MLA(hi, lo, (*fe)[0], ptr[ 0]);
603 MLA(hi, lo, (*fe)[1], ptr[14]);
604 MLA(hi, lo, (*fe)[2], ptr[12]);
605 MLA(hi, lo, (*fe)[3], ptr[10]);
606 MLA(hi, lo, (*fe)[4], ptr[ 8]);
607 MLA(hi, lo, (*fe)[5], ptr[ 6]);
608 MLA(hi, lo, (*fe)[6], ptr[ 4]);
609 MLA(hi, lo, (*fe)[7], ptr[ 2]);
610
611 *pcm1++ = SHIFT(MLZ(hi, lo));
612
613 pcm2 = pcm1 + 30;
614
615 for (sb = 1; sb < 16; ++sb) {
616 ++fe;
617 ++Dptr;
618
619 /* D[32 - sb][i] == -D[sb][31 - i] */
620
621 ptr = *Dptr + po;
622 ML0(hi, lo, (*fo)[0], ptr[ 0]);
623 MLA(hi, lo, (*fo)[1], ptr[14]);
624 MLA(hi, lo, (*fo)[2], ptr[12]);
625 MLA(hi, lo, (*fo)[3], ptr[10]);
626 MLA(hi, lo, (*fo)[4], ptr[ 8]);
627 MLA(hi, lo, (*fo)[5], ptr[ 6]);
628 MLA(hi, lo, (*fo)[6], ptr[ 4]);
629 MLA(hi, lo, (*fo)[7], ptr[ 2]);
630 MLN(hi, lo);
631
632 ptr = *Dptr + pe;
633 MLA(hi, lo, (*fe)[7], ptr[ 2]);
634 MLA(hi, lo, (*fe)[6], ptr[ 4]);
635 MLA(hi, lo, (*fe)[5], ptr[ 6]);
636 MLA(hi, lo, (*fe)[4], ptr[ 8]);
637 MLA(hi, lo, (*fe)[3], ptr[10]);
638 MLA(hi, lo, (*fe)[2], ptr[12]);
639 MLA(hi, lo, (*fe)[1], ptr[14]);
640 MLA(hi, lo, (*fe)[0], ptr[ 0]);
641
642 *pcm1++ = SHIFT(MLZ(hi, lo));
643
644 ptr = *Dptr - pe;
645 ML0(hi, lo, (*fe)[0], ptr[31 - 16]);
646 MLA(hi, lo, (*fe)[1], ptr[31 - 14]);
647 MLA(hi, lo, (*fe)[2], ptr[31 - 12]);
648 MLA(hi, lo, (*fe)[3], ptr[31 - 10]);
649 MLA(hi, lo, (*fe)[4], ptr[31 - 8]);
650 MLA(hi, lo, (*fe)[5], ptr[31 - 6]);
651 MLA(hi, lo, (*fe)[6], ptr[31 - 4]);
652 MLA(hi, lo, (*fe)[7], ptr[31 - 2]);
653
654 ptr = *Dptr - po;
655 MLA(hi, lo, (*fo)[7], ptr[31 - 2]);
656 MLA(hi, lo, (*fo)[6], ptr[31 - 4]);
657 MLA(hi, lo, (*fo)[5], ptr[31 - 6]);
658 MLA(hi, lo, (*fo)[4], ptr[31 - 8]);
659 MLA(hi, lo, (*fo)[3], ptr[31 - 10]);
660 MLA(hi, lo, (*fo)[2], ptr[31 - 12]);
661 MLA(hi, lo, (*fo)[1], ptr[31 - 14]);
662 MLA(hi, lo, (*fo)[0], ptr[31 - 16]);
663
664 *pcm2-- = SHIFT(MLZ(hi, lo));
665
666 ++fo;
667 }
668
669 ++Dptr;
670
671 ptr = *Dptr + po;
672 ML0(hi, lo, (*fo)[0], ptr[ 0]);
673 MLA(hi, lo, (*fo)[1], ptr[14]);
674 MLA(hi, lo, (*fo)[2], ptr[12]);
675 MLA(hi, lo, (*fo)[3], ptr[10]);
676 MLA(hi, lo, (*fo)[4], ptr[ 8]);
677 MLA(hi, lo, (*fo)[5], ptr[ 6]);
678 MLA(hi, lo, (*fo)[6], ptr[ 4]);
679 MLA(hi, lo, (*fo)[7], ptr[ 2]);
680
681 *pcm1 = SHIFT(-MLZ(hi, lo));
682 pcm1 += 16;
683
684 phase = (phase + 1) % 16;
685 }
686 }
687 }
688 # endif
689
690 /*
691 * NAME: synth->half()
692 * DESCRIPTION: perform half frequency PCM synthesis
693 */
694 static
synth_half(struct mad_synth * synth,struct mad_frame const * frame,unsigned int nch,unsigned int ns)695 void synth_half(struct mad_synth *synth, struct mad_frame const *frame,
696 unsigned int nch, unsigned int ns)
697 {
698 unsigned int phase, ch, s, sb, pe, po;
699 mad_fixed_t *pcm1, *pcm2, (*filter)[2][2][16][8];
700 mad_fixed_t const (*sbsample)[36][32];
701 register mad_fixed_t (*fe)[8], (*fx)[8], (*fo)[8];
702 register mad_fixed_t const (*Dptr)[32], *ptr;
703 register mad_fixed64hi_t hi;
704 register mad_fixed64lo_t lo;
705
706 for (ch = 0; ch < nch; ++ch) {
707 sbsample = &frame->sbsample[ch];
708 filter = &synth->filter[ch];
709 phase = synth->phase;
710 pcm1 = synth->pcm.samples[ch];
711
712 for (s = 0; s < ns; ++s) {
713 dct32((*sbsample)[s], phase >> 1,
714 (*filter)[0][phase & 1], (*filter)[1][phase & 1]);
715
716 pe = phase & ~1;
717 po = ((phase - 1) & 0xf) | 1;
718
719 /* calculate 16 samples */
720
721 fe = &(*filter)[0][ phase & 1][0];
722 fx = &(*filter)[0][~phase & 1][0];
723 fo = &(*filter)[1][~phase & 1][0];
724
725 Dptr = &D[0];
726
727 ptr = *Dptr + po;
728 ML0(hi, lo, (*fx)[0], ptr[ 0]);
729 MLA(hi, lo, (*fx)[1], ptr[14]);
730 MLA(hi, lo, (*fx)[2], ptr[12]);
731 MLA(hi, lo, (*fx)[3], ptr[10]);
732 MLA(hi, lo, (*fx)[4], ptr[ 8]);
733 MLA(hi, lo, (*fx)[5], ptr[ 6]);
734 MLA(hi, lo, (*fx)[6], ptr[ 4]);
735 MLA(hi, lo, (*fx)[7], ptr[ 2]);
736 MLN(hi, lo);
737
738 ptr = *Dptr + pe;
739 MLA(hi, lo, (*fe)[0], ptr[ 0]);
740 MLA(hi, lo, (*fe)[1], ptr[14]);
741 MLA(hi, lo, (*fe)[2], ptr[12]);
742 MLA(hi, lo, (*fe)[3], ptr[10]);
743 MLA(hi, lo, (*fe)[4], ptr[ 8]);
744 MLA(hi, lo, (*fe)[5], ptr[ 6]);
745 MLA(hi, lo, (*fe)[6], ptr[ 4]);
746 MLA(hi, lo, (*fe)[7], ptr[ 2]);
747
748 *pcm1++ = SHIFT(MLZ(hi, lo));
749
750 pcm2 = pcm1 + 14;
751
752 for (sb = 1; sb < 16; ++sb) {
753 ++fe;
754 ++Dptr;
755
756 /* D[32 - sb][i] == -D[sb][31 - i] */
757
758 if (!(sb & 1)) {
759 ptr = *Dptr + po;
760 ML0(hi, lo, (*fo)[0], ptr[ 0]);
761 MLA(hi, lo, (*fo)[1], ptr[14]);
762 MLA(hi, lo, (*fo)[2], ptr[12]);
763 MLA(hi, lo, (*fo)[3], ptr[10]);
764 MLA(hi, lo, (*fo)[4], ptr[ 8]);
765 MLA(hi, lo, (*fo)[5], ptr[ 6]);
766 MLA(hi, lo, (*fo)[6], ptr[ 4]);
767 MLA(hi, lo, (*fo)[7], ptr[ 2]);
768 MLN(hi, lo);
769
770 ptr = *Dptr + pe;
771 MLA(hi, lo, (*fe)[7], ptr[ 2]);
772 MLA(hi, lo, (*fe)[6], ptr[ 4]);
773 MLA(hi, lo, (*fe)[5], ptr[ 6]);
774 MLA(hi, lo, (*fe)[4], ptr[ 8]);
775 MLA(hi, lo, (*fe)[3], ptr[10]);
776 MLA(hi, lo, (*fe)[2], ptr[12]);
777 MLA(hi, lo, (*fe)[1], ptr[14]);
778 MLA(hi, lo, (*fe)[0], ptr[ 0]);
779
780 *pcm1++ = SHIFT(MLZ(hi, lo));
781
782 ptr = *Dptr - po;
783 ML0(hi, lo, (*fo)[7], ptr[31 - 2]);
784 MLA(hi, lo, (*fo)[6], ptr[31 - 4]);
785 MLA(hi, lo, (*fo)[5], ptr[31 - 6]);
786 MLA(hi, lo, (*fo)[4], ptr[31 - 8]);
787 MLA(hi, lo, (*fo)[3], ptr[31 - 10]);
788 MLA(hi, lo, (*fo)[2], ptr[31 - 12]);
789 MLA(hi, lo, (*fo)[1], ptr[31 - 14]);
790 MLA(hi, lo, (*fo)[0], ptr[31 - 16]);
791
792 ptr = *Dptr - pe;
793 MLA(hi, lo, (*fe)[0], ptr[31 - 16]);
794 MLA(hi, lo, (*fe)[1], ptr[31 - 14]);
795 MLA(hi, lo, (*fe)[2], ptr[31 - 12]);
796 MLA(hi, lo, (*fe)[3], ptr[31 - 10]);
797 MLA(hi, lo, (*fe)[4], ptr[31 - 8]);
798 MLA(hi, lo, (*fe)[5], ptr[31 - 6]);
799 MLA(hi, lo, (*fe)[6], ptr[31 - 4]);
800 MLA(hi, lo, (*fe)[7], ptr[31 - 2]);
801
802 *pcm2-- = SHIFT(MLZ(hi, lo));
803 }
804
805 ++fo;
806 }
807
808 ++Dptr;
809
810 ptr = *Dptr + po;
811 ML0(hi, lo, (*fo)[0], ptr[ 0]);
812 MLA(hi, lo, (*fo)[1], ptr[14]);
813 MLA(hi, lo, (*fo)[2], ptr[12]);
814 MLA(hi, lo, (*fo)[3], ptr[10]);
815 MLA(hi, lo, (*fo)[4], ptr[ 8]);
816 MLA(hi, lo, (*fo)[5], ptr[ 6]);
817 MLA(hi, lo, (*fo)[6], ptr[ 4]);
818 MLA(hi, lo, (*fo)[7], ptr[ 2]);
819
820 *pcm1 = SHIFT(-MLZ(hi, lo));
821 pcm1 += 8;
822
823 phase = (phase + 1) % 16;
824 }
825 }
826 }
827
828 /*
829 * NAME: synth->frame()
830 * DESCRIPTION: perform PCM synthesis of frame subband samples
831 */
mad_synth_frame(struct mad_synth * synth,struct mad_frame const * frame)832 void mad_synth_frame(struct mad_synth *synth, struct mad_frame const *frame)
833 {
834 unsigned int nch, ns;
835 void (*synth_frame)(struct mad_synth *, struct mad_frame const *,
836 unsigned int, unsigned int);
837
838 nch = MAD_NCHANNELS(&frame->header);
839 ns = MAD_NSBSAMPLES(&frame->header);
840
841 synth->pcm.samplerate = frame->header.samplerate;
842 synth->pcm.channels = nch;
843 synth->pcm.length = 32 * ns;
844
845 synth_frame = synth_full;
846
847 if (frame->options & MAD_OPTION_HALFSAMPLERATE) {
848 synth->pcm.samplerate /= 2;
849 synth->pcm.length /= 2;
850
851 synth_frame = synth_half;
852 }
853
854 synth_frame(synth, frame, nch, ns);
855
856 synth->phase = (synth->phase + ns) % 16;
857 }
858