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/*
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 * parse.c
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 * Copyright (C) 2000-2003 Michel Lespinasse <walken@zoy.org>
4
 * Copyright (C) 1999-2000 Aaron Holtzman <aholtzma@ess.engr.uvic.ca>
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 *
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 * This file is part of a52dec, a free ATSC A-52 stream decoder.
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 * See http://liba52.sourceforge.net/ for updates.
8
 *
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 * a52dec is free software; you can redistribute it and/or modify
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 * it under the terms of the GNU General Public License as published by
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 * the Free Software Foundation; either version 2 of the License, or
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 * (at your option) any later version.
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 *
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 * a52dec is distributed in the hope that it will be useful,
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 * but WITHOUT ANY WARRANTY; without even the implied warranty of
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 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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 * GNU General Public License for more details.
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 *
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 * You should have received a copy of the GNU General Public License
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 * along with this program; if not, write to the Free Software
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 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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 */
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#include "a52.h"
24
#include "a52_internal.h"
25
#include "bitstream.h"
26
#include "tables.h"
27

    
28
#if defined(HAVE_MEMALIGN) && !defined(__cplusplus)
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/* some systems have memalign() but no declaration for it */
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void * memalign (size_t align, size_t size);
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#else
32
/* assume malloc alignment is sufficient */
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#define memalign(align,size) malloc (size)
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#endif
35

    
36
typedef struct {
37
    quantizer_t q1[2];
38
    quantizer_t q2[2];
39
    quantizer_t q4;
40
    int q1_ptr;
41
    int q2_ptr;
42
    int q4_ptr;
43
} quantizer_set_t;
44

    
45
static uint8_t halfrate[12] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 2, 3};
46

    
47
a52_state_t * a52_init (uint32_t mm_accel)
48
{
49
    a52_state_t * state;
50
    int i;
51

    
52
    state = (a52_state_t *) malloc (sizeof (a52_state_t));
53
    if (state == NULL)
54
        return NULL;
55

    
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    state->samples = (sample_t *) memalign (16, 256 * 12 * sizeof (sample_t));
57
    if (state->samples == NULL) {
58
        free (state);
59
        return NULL;
60
    }
61

    
62
    for (i = 0; i < 256 * 12; i++)
63
        state->samples[i] = 0;
64

    
65
    state->downmixed = 1;
66

    
67
    state->lfsr_state = 1;
68

    
69
    a52_imdct_init (mm_accel);
70

    
71
    return state;
72
}
73

    
74
sample_t * a52_samples (a52_state_t * state)
75
{
76
    return state->samples;
77
}
78

    
79
int a52_syncinfo (uint8_t * buf, int * flags,
80
                  int * sample_rate, int * bit_rate)
81
{
82
    static int rate[] = { 32,  40,  48,  56,  64,  80,  96, 112,
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                         128, 160, 192, 224, 256, 320, 384, 448,
84
                         512, 576, 640};
85
    static uint8_t lfeon[8] = {0x10, 0x10, 0x04, 0x04, 0x04, 0x01, 0x04, 0x01};
86
    int frmsizecod;
87
    int bitrate;
88
    int half;
89
    int acmod;
90

    
91
    if ((buf[0] != 0x0b) || (buf[1] != 0x77))        /* syncword */
92
        return 0;
93

    
94
    if (buf[5] >= 0x60)                /* bsid >= 12 */
95
        return 0;
96
    half = halfrate[buf[5] >> 3];
97

    
98
    /* acmod, dsurmod and lfeon */
99
    acmod = buf[6] >> 5;
100
    *flags = ((((buf[6] & 0xf8) == 0x50) ? A52_DOLBY : acmod) |
101
              ((buf[6] & lfeon[acmod]) ? A52_LFE : 0));
102

    
103
    frmsizecod = buf[4] & 63;
104
    if (frmsizecod >= 38)
105
        return 0;
106
    bitrate = rate [frmsizecod >> 1];
107
    *bit_rate = (bitrate * 1000) >> half;
108

    
109
    switch (buf[4] & 0xc0) {
110
    case 0:
111
        *sample_rate = 48000 >> half;
112
        return 4 * bitrate;
113
    case 0x40:
114
        *sample_rate = 44100 >> half;
115
        return 2 * (320 * bitrate / 147 + (frmsizecod & 1));
116
    case 0x80:
117
        *sample_rate = 32000 >> half;
118
        return 6 * bitrate;
119
    default:
120
        return 0;
121
    }
122
}
123

    
124
int a52_frame (a52_state_t * state, uint8_t * buf, int * flags,
125
               level_t * level, sample_t bias)
126
{
127
    static level_t clev[4] = { LEVEL (LEVEL_3DB), LEVEL (LEVEL_45DB),
128
                               LEVEL (LEVEL_6DB), LEVEL (LEVEL_45DB) };
129
    static level_t slev[4] = { LEVEL (LEVEL_3DB), LEVEL (LEVEL_6DB),
130
                               0,                 LEVEL (LEVEL_6DB) };
131
    int chaninfo;
132
    int acmod;
133

    
134
    state->fscod = buf[4] >> 6;
135
    state->halfrate = halfrate[buf[5] >> 3];
136
    state->acmod = acmod = buf[6] >> 5;
137

    
138
    a52_bitstream_set_ptr (state, buf + 6);
139
    bitstream_get (state, 3);        /* skip acmod we already parsed */
140

    
141
    if ((acmod == 2) && (bitstream_get (state, 2) == 2))        /* dsurmod */
142
        acmod = A52_DOLBY;
143

    
144
    state->clev = state->slev = 0;
145

    
146
    if ((acmod & 1) && (acmod != 1))
147
        state->clev = clev[bitstream_get (state, 2)];        /* cmixlev */
148

    
149
    if (acmod & 4)
150
        state->slev = slev[bitstream_get (state, 2)];        /* surmixlev */
151

    
152
    state->lfeon = bitstream_get (state, 1);
153

    
154
    state->output = a52_downmix_init (acmod, *flags, level,
155
                                      state->clev, state->slev);
156
    if (state->output < 0)
157
        return 1;
158
    if (state->lfeon && (*flags & A52_LFE))
159
        state->output |= A52_LFE;
160
    *flags = state->output;
161
    /* the 2* compensates for differences in imdct */
162
    state->dynrng = state->level = MUL_C (*level, 2);
163
    state->bias = bias;
164
    state->dynrnge = 1;
165
    state->dynrngcall = NULL;
166
    state->cplba.deltbae = DELTA_BIT_NONE;
167
    state->ba[0].deltbae = state->ba[1].deltbae = state->ba[2].deltbae =
168
        state->ba[3].deltbae = state->ba[4].deltbae = DELTA_BIT_NONE;
169

    
170
    chaninfo = !acmod;
171
    do {
172
        bitstream_get (state, 5);        /* dialnorm */
173
        if (bitstream_get (state, 1))        /* compre */
174
            bitstream_get (state, 8);        /* compr */
175
        if (bitstream_get (state, 1))        /* langcode */
176
            bitstream_get (state, 8);        /* langcod */
177
        if (bitstream_get (state, 1))        /* audprodie */
178
            bitstream_get (state, 7);        /* mixlevel + roomtyp */
179
    } while (chaninfo--);
180

    
181
    bitstream_get (state, 2);                /* copyrightb + origbs */
182

    
183
    if (bitstream_get (state, 1))        /* timecod1e */
184
        bitstream_get (state, 14);        /* timecod1 */
185
    if (bitstream_get (state, 1))        /* timecod2e */
186
        bitstream_get (state, 14);        /* timecod2 */
187

    
188
    if (bitstream_get (state, 1)) {        /* addbsie */
189
        int addbsil;
190

    
191
        addbsil = bitstream_get (state, 6);
192
        do {
193
            bitstream_get (state, 8);        /* addbsi */
194
        } while (addbsil--);
195
    }
196

    
197
    return 0;
198
}
199

    
200
void a52_dynrng (a52_state_t * state,
201
                 level_t (* call) (level_t, void *), void * data)
202
{
203
    state->dynrnge = 0;
204
    if (call) {
205
        state->dynrnge = 1;
206
        state->dynrngcall = call;
207
        state->dynrngdata = data;
208
    }
209
}
210

    
211
static int parse_exponents (a52_state_t * state, int expstr, int ngrps,
212
                            uint8_t exponent, uint8_t * dest)
213
{
214
    int exps;
215

    
216
    while (ngrps--) {
217
        exps = bitstream_get (state, 7);
218

    
219
        exponent += exp_1[exps];
220
        if (exponent > 24)
221
            return 1;
222

    
223
        switch (expstr) {
224
        case EXP_D45:
225
            *(dest++) = exponent;
226
            *(dest++) = exponent;
227
        case EXP_D25:
228
            *(dest++) = exponent;
229
        case EXP_D15:
230
            *(dest++) = exponent;
231
        }
232

    
233
        exponent += exp_2[exps];
234
        if (exponent > 24)
235
            return 1;
236

    
237
        switch (expstr) {
238
        case EXP_D45:
239
            *(dest++) = exponent;
240
            *(dest++) = exponent;
241
        case EXP_D25:
242
            *(dest++) = exponent;
243
        case EXP_D15:
244
            *(dest++) = exponent;
245
        }
246

    
247
        exponent += exp_3[exps];
248
        if (exponent > 24)
249
            return 1;
250

    
251
        switch (expstr) {
252
        case EXP_D45:
253
            *(dest++) = exponent;
254
            *(dest++) = exponent;
255
        case EXP_D25:
256
            *(dest++) = exponent;
257
        case EXP_D15:
258
            *(dest++) = exponent;
259
        }
260
    }
261

    
262
    return 0;
263
}
264

    
265
static int parse_deltba (a52_state_t * state, int8_t * deltba)
266
{
267
    int deltnseg, deltlen, delta, j;
268

    
269
    memset (deltba, 0, 50);
270

    
271
    deltnseg = bitstream_get (state, 3);
272
    j = 0;
273
    do {
274
        j += bitstream_get (state, 5);
275
        deltlen = bitstream_get (state, 4);
276
        delta = bitstream_get (state, 3);
277
        delta -= (delta >= 4) ? 3 : 4;
278
        if (!deltlen)
279
            continue;
280
        if (j + deltlen >= 50)
281
            return 1;
282
        while (deltlen--)
283
            deltba[j++] = delta;
284
    } while (deltnseg--);
285

    
286
    return 0;
287
}
288

    
289
static inline int zero_snr_offsets (int nfchans, a52_state_t * state)
290
{
291
    int i;
292

    
293
    if ((state->csnroffst) ||
294
        (state->chincpl && state->cplba.bai >> 3) ||        /* cplinu, fsnroffst */
295
        (state->lfeon && state->lfeba.bai >> 3))        /* fsnroffst */
296
        return 0;
297
    for (i = 0; i < nfchans; i++)
298
        if (state->ba[i].bai >> 3)                        /* fsnroffst */
299
            return 0;
300
    return 1;
301
}
302

    
303
static inline int16_t dither_gen (a52_state_t * state)
304
{
305
    int16_t nstate;
306

    
307
    nstate = dither_lut[state->lfsr_state >> 8] ^ (state->lfsr_state << 8);
308

    
309
    state->lfsr_state = (uint16_t) nstate;
310

    
311
    return (3 * nstate) >> 2;
312
}
313

    
314
#ifndef LIBA52_FIXED
315
#define COEFF(c,t,l,s,e) (c) = (t) * (s)[e]
316
#else
317
#define COEFF(c,_t,_l,s,e) do {                                        \
318
    quantizer_t t = (_t);                                        \
319
    level_t l = (_l);                                                \
320
    int shift = e - 5;                                                \
321
    sample_t tmp = t * (l >> 16) + ((t * (l & 0xffff)) >> 16);        \
322
    if (shift >= 0)                                                \
323
        (c) = tmp >> shift;                                        \
324
    else                                                        \
325
        (c) = tmp << -shift;                                        \
326
} while (0)
327
#endif
328

    
329
static void coeff_get (a52_state_t * state, sample_t * coeff,
330
                       expbap_t * expbap, quantizer_set_t * quant,
331
                       level_t level, int dither, int end)
332
{
333
    int i;
334
    uint8_t * exp;
335
    int8_t * bap;
336

    
337
#ifndef LIBA52_FIXED
338
    sample_t factor[25];
339

    
340
    for (i = 0; i <= 24; i++)
341
        factor[i] = scale_factor[i] * level;
342
#endif
343

    
344
    exp = expbap->exp;
345
    bap = expbap->bap;
346

    
347
    for (i = 0; i < end; i++) {
348
        int bapi;
349

    
350
        bapi = bap[i];
351
        switch (bapi) {
352
        case 0:
353
            if (dither) {
354
                COEFF (coeff[i], dither_gen (state), level, factor, exp[i]);
355
                continue;
356
            } else {
357
                coeff[i] = 0;
358
                continue;
359
            }
360

    
361
        case -1:
362
            if (quant->q1_ptr >= 0) {
363
                COEFF (coeff[i], quant->q1[quant->q1_ptr--], level,
364
                       factor, exp[i]);
365
                continue;
366
            } else {
367
                int code;
368

    
369
                code = bitstream_get (state, 5);
370

    
371
                quant->q1_ptr = 1;
372
                quant->q1[0] = q_1_2[code];
373
                quant->q1[1] = q_1_1[code];
374
                COEFF (coeff[i], q_1_0[code], level, factor, exp[i]);
375
                continue;
376
            }
377

    
378
        case -2:
379
            if (quant->q2_ptr >= 0) {
380
                COEFF (coeff[i], quant->q2[quant->q2_ptr--], level,
381
                       factor, exp[i]);
382
                continue;
383
            } else {
384
                int code;
385

    
386
                code = bitstream_get (state, 7);
387

    
388
                quant->q2_ptr = 1;
389
                quant->q2[0] = q_2_2[code];
390
                quant->q2[1] = q_2_1[code];
391
                COEFF (coeff[i], q_2_0[code], level, factor, exp[i]);
392
                continue;
393
            }
394

    
395
        case 3:
396
            COEFF (coeff[i], q_3[bitstream_get (state, 3)], level,
397
                   factor, exp[i]);
398
            continue;
399

    
400
        case -3:
401
            if (quant->q4_ptr == 0) {
402
                quant->q4_ptr = -1;
403
                COEFF (coeff[i], quant->q4, level, factor, exp[i]);
404
                continue;
405
            } else {
406
                int code;
407

    
408
                code = bitstream_get (state, 7);
409

    
410
                quant->q4_ptr = 0;
411
                quant->q4 = q_4_1[code];
412
                COEFF (coeff[i], q_4_0[code], level, factor, exp[i]);
413
                continue;
414
            }
415

    
416
        case 4:
417
            COEFF (coeff[i], q_5[bitstream_get (state, 4)], level,
418
                   factor, exp[i]);
419
            continue;
420

    
421
        default:
422
            COEFF (coeff[i], bitstream_get_2 (state, bapi) << (16 - bapi),
423
                   level, factor, exp[i]);
424
        }
425
    }
426
}
427

    
428
static void coeff_get_coupling (a52_state_t * state, int nfchans,
429
                                level_t * coeff, sample_t (* samples)[256],
430
                                quantizer_set_t * quant, uint8_t dithflag[5])
431
{
432
    int cplbndstrc, bnd, i, i_end, ch;
433
    uint8_t * exp;
434
    int8_t * bap;
435
    level_t cplco[5];
436

    
437
    exp = state->cpl_expbap.exp;
438
    bap = state->cpl_expbap.bap;
439
    bnd = 0;
440
    cplbndstrc = state->cplbndstrc;
441
    i = state->cplstrtmant;
442
    while (i < state->cplendmant) {
443
        i_end = i + 12;
444
        while (cplbndstrc & 1) {
445
            cplbndstrc >>= 1;
446
            i_end += 12;
447
        }
448
        cplbndstrc >>= 1;
449
        for (ch = 0; ch < nfchans; ch++)
450
            cplco[ch] = MUL_L (state->cplco[ch][bnd], coeff[ch]);
451
        bnd++;
452

    
453
        while (i < i_end) {
454
            quantizer_t cplcoeff;
455
            int bapi;
456

    
457
            bapi = bap[i];
458
            switch (bapi) {
459
            case 0:
460
                for (ch = 0; ch < nfchans; ch++)
461
                    if ((state->chincpl >> ch) & 1) {
462
                        if (dithflag[ch])
463
#ifndef LIBA52_FIXED
464
                            samples[ch][i] = (scale_factor[exp[i]] *
465
                                              cplco[ch] * dither_gen (state));
466
#else
467
                            COEFF (samples[ch][i], dither_gen (state),
468
                                   cplco[ch], scale_factor, exp[i]);
469
#endif
470
                        else
471
                            samples[ch][i] = 0;
472
                    }
473
                i++;
474
                continue;
475

    
476
            case -1:
477
                if (quant->q1_ptr >= 0) {
478
                    cplcoeff = quant->q1[quant->q1_ptr--];
479
                    break;
480
                } else {
481
                    int code;
482

    
483
                    code = bitstream_get (state, 5);
484

    
485
                    quant->q1_ptr = 1;
486
                    quant->q1[0] = q_1_2[code];
487
                    quant->q1[1] = q_1_1[code];
488
                    cplcoeff = q_1_0[code];
489
                    break;
490
                }
491

    
492
            case -2:
493
                if (quant->q2_ptr >= 0) {
494
                    cplcoeff = quant->q2[quant->q2_ptr--];
495
                    break;
496
                } else {
497
                    int code;
498

    
499
                    code = bitstream_get (state, 7);
500

    
501
                    quant->q2_ptr = 1;
502
                    quant->q2[0] = q_2_2[code];
503
                    quant->q2[1] = q_2_1[code];
504
                    cplcoeff = q_2_0[code];
505
                    break;
506
                }
507

    
508
            case 3:
509
                cplcoeff = q_3[bitstream_get (state, 3)];
510
                break;
511

    
512
            case -3:
513
                if (quant->q4_ptr == 0) {
514
                    quant->q4_ptr = -1;
515
                    cplcoeff = quant->q4;
516
                    break;
517
                } else {
518
                    int code;
519

    
520
                    code = bitstream_get (state, 7);
521

    
522
                    quant->q4_ptr = 0;
523
                    quant->q4 = q_4_1[code];
524
                    cplcoeff = q_4_0[code];
525
                    break;
526
                }
527

    
528
            case 4:
529
                cplcoeff = q_5[bitstream_get (state, 4)];
530
                break;
531

    
532
            default:
533
                cplcoeff = bitstream_get_2 (state, bapi) << (16 - bapi);
534
            }
535
#ifndef LIBA52_FIXED
536
            cplcoeff *= scale_factor[exp[i]];
537
#endif
538
            for (ch = 0; ch < nfchans; ch++)
539
               if ((state->chincpl >> ch) & 1)
540
#ifndef LIBA52_FIXED
541
                    samples[ch][i] = cplcoeff * cplco[ch];
542
#else
543
                    COEFF (samples[ch][i], cplcoeff, cplco[ch],
544
                           scale_factor, exp[i]);
545
#endif
546
            i++;
547
        }
548
    }
549
}
550

    
551
int a52_block (a52_state_t * state)
552
{
553
    static const uint8_t nfchans_tbl[] = {2, 1, 2, 3, 3, 4, 4, 5, 1, 1, 2};
554
    static int rematrix_band[4] = {25, 37, 61, 253};
555
    int i, nfchans, chaninfo;
556
    uint8_t cplexpstr, chexpstr[5], lfeexpstr, do_bit_alloc, done_cpl;
557
    uint8_t blksw[5], dithflag[5];
558
    level_t coeff[5];
559
    int chanbias;
560
    quantizer_set_t quant;
561
    sample_t * samples;
562

    
563
    nfchans = nfchans_tbl[state->acmod];
564

    
565
    for (i = 0; i < nfchans; i++)
566
        blksw[i] = bitstream_get (state, 1);
567

    
568
    for (i = 0; i < nfchans; i++)
569
        dithflag[i] = bitstream_get (state, 1);
570

    
571
    chaninfo = !state->acmod;
572
    do {
573
        if (bitstream_get (state, 1)) {        /* dynrnge */
574
            int dynrng;
575

    
576
            dynrng = bitstream_get_2 (state, 8);
577
            if (state->dynrnge) {
578
                level_t range;
579

    
580
#if !defined(LIBA52_FIXED)
581
                range = ((((dynrng & 0x1f) | 0x20) << 13) *
582
                         scale_factor[3 - (dynrng >> 5)]);
583
#else
584
                range = ((dynrng & 0x1f) | 0x20) << (21 + (dynrng >> 5));
585
#endif
586
                if (state->dynrngcall)
587
                    range = state->dynrngcall (range, state->dynrngdata);
588
                state->dynrng = MUL_L (state->level, range);
589
            }
590
        }
591
    } while (chaninfo--);
592

    
593
    if (bitstream_get (state, 1)) {        /* cplstre */
594
        state->chincpl = 0;
595
        if (bitstream_get (state, 1)) {        /* cplinu */
596
            static uint8_t bndtab[16] = {31, 35, 37, 39, 41, 42, 43, 44,
597
                                         45, 45, 46, 46, 47, 47, 48, 48};
598
            int cplbegf;
599
            int cplendf;
600
            int ncplsubnd;
601

    
602
            for (i = 0; i < nfchans; i++)
603
                state->chincpl |= bitstream_get (state, 1) << i;
604
            switch (state->acmod) {
605
            case 0: case 1:
606
                return 1;
607
            case 2:
608
                state->phsflginu = bitstream_get (state, 1);
609
            }
610
            cplbegf = bitstream_get (state, 4);
611
            cplendf = bitstream_get (state, 4);
612

    
613
            if (cplendf + 3 - cplbegf < 0)
614
                return 1;
615
            state->ncplbnd = ncplsubnd = cplendf + 3 - cplbegf;
616
            state->cplstrtbnd = bndtab[cplbegf];
617
            state->cplstrtmant = cplbegf * 12 + 37;
618
            state->cplendmant = cplendf * 12 + 73;
619

    
620
            state->cplbndstrc = 0;
621
            for (i = 0; i < ncplsubnd - 1; i++)
622
                if (bitstream_get (state, 1)) {
623
                    state->cplbndstrc |= 1 << i;
624
                    state->ncplbnd--;
625
                }
626
        }
627
    }
628

    
629
    if (state->chincpl) {        /* cplinu */
630
        int j, cplcoe;
631

    
632
        cplcoe = 0;
633
        for (i = 0; i < nfchans; i++)
634
            if ((state->chincpl) >> i & 1)
635
                if (bitstream_get (state, 1)) {        /* cplcoe */
636
                    int mstrcplco, cplcoexp, cplcomant;
637

    
638
                    cplcoe = 1;
639
                    mstrcplco = 3 * bitstream_get (state, 2);
640
                    for (j = 0; j < state->ncplbnd; j++) {
641
                        cplcoexp = bitstream_get (state, 4);
642
                        cplcomant = bitstream_get (state, 4);
643
                        if (cplcoexp == 15)
644
                            cplcomant <<= 14;
645
                        else
646
                            cplcomant = (cplcomant | 0x10) << 13;
647
#ifndef LIBA52_FIXED
648
                        state->cplco[i][j] =
649
                            cplcomant * scale_factor[cplcoexp + mstrcplco];
650
#else
651
                        state->cplco[i][j] = (cplcomant << 11) >> (cplcoexp + mstrcplco);
652
#endif
653

    
654
                    }
655
                }
656
        if ((state->acmod == 2) && state->phsflginu && cplcoe)
657
            for (j = 0; j < state->ncplbnd; j++)
658
                if (bitstream_get (state, 1))        /* phsflg */
659
                    state->cplco[1][j] = -state->cplco[1][j];
660
    }
661

    
662
    if ((state->acmod == 2) && (bitstream_get (state, 1))) {        /* rematstr */
663
        int end;
664

    
665
        state->rematflg = 0;
666
        end = (state->chincpl) ? state->cplstrtmant : 253;        /* cplinu */
667
        i = 0;
668
        do
669
            state->rematflg |= bitstream_get (state, 1) << i;
670
        while (rematrix_band[i++] < end);
671
    }
672

    
673
    cplexpstr = EXP_REUSE;
674
    lfeexpstr = EXP_REUSE;
675
    if (state->chincpl)        /* cplinu */
676
        cplexpstr = bitstream_get (state, 2);
677
    for (i = 0; i < nfchans; i++)
678
        chexpstr[i] = bitstream_get (state, 2);
679
    if (state->lfeon)
680
        lfeexpstr = bitstream_get (state, 1);
681

    
682
    for (i = 0; i < nfchans; i++)
683
        if (chexpstr[i] != EXP_REUSE) {
684
            if ((state->chincpl >> i) & 1)
685
                state->endmant[i] = state->cplstrtmant;
686
            else {
687
                int chbwcod;
688

    
689
                chbwcod = bitstream_get (state, 6);
690
                if (chbwcod > 60)
691
                    return 1;
692
                state->endmant[i] = chbwcod * 3 + 73;
693
            }
694
        }
695

    
696
    do_bit_alloc = 0;
697

    
698
    if (cplexpstr != EXP_REUSE) {
699
        int cplabsexp, ncplgrps;
700

    
701
        do_bit_alloc = 64;
702
        ncplgrps = ((state->cplendmant - state->cplstrtmant) /
703
                    (3 << (cplexpstr - 1)));
704
        cplabsexp = bitstream_get (state, 4) << 1;
705
        if (parse_exponents (state, cplexpstr, ncplgrps, cplabsexp,
706
                             state->cpl_expbap.exp + state->cplstrtmant))
707
            return 1;
708
    }
709
    for (i = 0; i < nfchans; i++)
710
        if (chexpstr[i] != EXP_REUSE) {
711
            int grp_size, nchgrps;
712

    
713
            do_bit_alloc |= 1 << i;
714
            grp_size = 3 << (chexpstr[i] - 1);
715
            nchgrps = (state->endmant[i] + grp_size - 4) / grp_size;
716
            state->fbw_expbap[i].exp[0] = bitstream_get (state, 4);
717
            if (parse_exponents (state, chexpstr[i], nchgrps,
718
                                 state->fbw_expbap[i].exp[0],
719
                                 state->fbw_expbap[i].exp + 1))
720
                return 1;
721
            bitstream_get (state, 2);        /* gainrng */
722
        }
723
    if (lfeexpstr != EXP_REUSE) {
724
        do_bit_alloc |= 32;
725
        state->lfe_expbap.exp[0] = bitstream_get (state, 4);
726
        if (parse_exponents (state, lfeexpstr, 2, state->lfe_expbap.exp[0],
727
                             state->lfe_expbap.exp + 1))
728
            return 1;
729
    }
730

    
731
    if (bitstream_get (state, 1)) {        /* baie */
732
        do_bit_alloc = 127;
733
        state->bai = bitstream_get (state, 11);
734
    }
735
    if (bitstream_get (state, 1)) {        /* snroffste */
736
        do_bit_alloc = 127;
737
        state->csnroffst = bitstream_get (state, 6);
738
        if (state->chincpl)        /* cplinu */
739
            state->cplba.bai = bitstream_get (state, 7);
740
        for (i = 0; i < nfchans; i++)
741
            state->ba[i].bai = bitstream_get (state, 7);
742
        if (state->lfeon)
743
            state->lfeba.bai = bitstream_get (state, 7);
744
    }
745
    if ((state->chincpl) && (bitstream_get (state, 1))) { /* cplleake */
746
        do_bit_alloc |= 64;
747
        state->cplfleak = 9 - bitstream_get (state, 3);
748
        state->cplsleak = 9 - bitstream_get (state, 3);
749
    }
750

    
751
    if (bitstream_get (state, 1)) {        /* deltbaie */
752
        do_bit_alloc = 127;
753
        if (state->chincpl)        /* cplinu */
754
            state->cplba.deltbae = bitstream_get (state, 2);
755
        for (i = 0; i < nfchans; i++)
756
            state->ba[i].deltbae = bitstream_get (state, 2);
757
        if (state->chincpl &&        /* cplinu */
758
            (state->cplba.deltbae == DELTA_BIT_NEW) &&
759
            parse_deltba (state, state->cplba.deltba))
760
            return 1;
761
        for (i = 0; i < nfchans; i++)
762
            if ((state->ba[i].deltbae == DELTA_BIT_NEW) &&
763
                parse_deltba (state, state->ba[i].deltba))
764
                return 1;
765
    }
766

    
767
    if (do_bit_alloc) {
768
        if (zero_snr_offsets (nfchans, state)) {
769
            memset (state->cpl_expbap.bap, 0, sizeof (state->cpl_expbap.bap));
770
            for (i = 0; i < nfchans; i++)
771
                memset (state->fbw_expbap[i].bap, 0,
772
                        sizeof (state->fbw_expbap[i].bap));
773
            memset (state->lfe_expbap.bap, 0, sizeof (state->lfe_expbap.bap));
774
        } else {
775
            if (state->chincpl && (do_bit_alloc & 64))        /* cplinu */
776
                a52_bit_allocate (state, &state->cplba, state->cplstrtbnd,
777
                                  state->cplstrtmant, state->cplendmant,
778
                                  state->cplfleak << 8, state->cplsleak << 8,
779
                                  &state->cpl_expbap);
780
            for (i = 0; i < nfchans; i++)
781
                if (do_bit_alloc & (1 << i))
782
                    a52_bit_allocate (state, state->ba + i, 0, 0,
783
                                      state->endmant[i], 0, 0,
784
                                      state->fbw_expbap +i);
785
            if (state->lfeon && (do_bit_alloc & 32)) {
786
                state->lfeba.deltbae = DELTA_BIT_NONE;
787
                a52_bit_allocate (state, &state->lfeba, 0, 0, 7, 0, 0,
788
                                  &state->lfe_expbap);
789
            }
790
        }
791
    }
792

    
793
    if (bitstream_get (state, 1)) {        /* skiple */
794
        i = bitstream_get (state, 9);        /* skipl */
795
        while (i--)
796
            bitstream_get (state, 8);
797
    }
798

    
799
    samples = state->samples;
800
    if (state->output & A52_LFE)
801
        samples += 256;        /* shift for LFE channel */
802

    
803
    chanbias = a52_downmix_coeff (coeff, state->acmod, state->output,
804
                                  state->dynrng, state->clev, state->slev);
805

    
806
    quant.q1_ptr = quant.q2_ptr = quant.q4_ptr = -1;
807
    done_cpl = 0;
808

    
809
    for (i = 0; i < nfchans; i++) {
810
        int j;
811

    
812
        coeff_get (state, samples + 256 * i, state->fbw_expbap +i, &quant,
813
                   coeff[i], dithflag[i], state->endmant[i]);
814

    
815
        if ((state->chincpl >> i) & 1) {
816
            if (!done_cpl) {
817
                done_cpl = 1;
818
                coeff_get_coupling (state, nfchans, coeff,
819
                                    (sample_t (*)[256])samples, &quant,
820
                                    dithflag);
821
            }
822
            j = state->cplendmant;
823
        } else
824
            j = state->endmant[i];
825
        do
826
            (samples + 256 * i)[j] = 0;
827
        while (++j < 256);
828
    }
829

    
830
    if (state->acmod == 2) {
831
        int j, end, band, rematflg;
832

    
833
        end = ((state->endmant[0] < state->endmant[1]) ?
834
               state->endmant[0] : state->endmant[1]);
835

    
836
        i = 0;
837
        j = 13;
838
        rematflg = state->rematflg;
839
        do {
840
            if (! (rematflg & 1)) {
841
                rematflg >>= 1;
842
                j = rematrix_band[i++];
843
                continue;
844
            }
845
            rematflg >>= 1;
846
            band = rematrix_band[i++];
847
            if (band > end)
848
                band = end;
849
            do {
850
                sample_t tmp0, tmp1;
851

    
852
                tmp0 = samples[j];
853
                tmp1 = (samples+256)[j];
854
                samples[j] = tmp0 + tmp1;
855
                (samples+256)[j] = tmp0 - tmp1;
856
            } while (++j < band);
857
        } while (j < end);
858
    }
859

    
860
    if (state->lfeon) {
861
        if (state->output & A52_LFE) {
862
            coeff_get (state, samples - 256, &state->lfe_expbap, &quant,
863
                       state->dynrng, 0, 7);
864
            for (i = 7; i < 256; i++)
865
                (samples-256)[i] = 0;
866
            a52_imdct_512 (samples - 256, samples + 1536 - 256, state->bias);
867
        } else {
868
            /* just skip the LFE coefficients */
869
            coeff_get (state, samples + 1280, &state->lfe_expbap, &quant,
870
                       0, 0, 7);
871
        }
872
    }
873

    
874
    i = 0;
875
    if (nfchans_tbl[state->output & A52_CHANNEL_MASK] < nfchans)
876
        for (i = 1; i < nfchans; i++)
877
            if (blksw[i] != blksw[0])
878
                break;
879

    
880
    if (i < nfchans) {
881
        if (state->downmixed) {
882
            state->downmixed = 0;
883
            a52_upmix (samples + 1536, state->acmod, state->output);
884
        }
885

    
886
        for (i = 0; i < nfchans; i++) {
887
            sample_t bias;
888

    
889
            bias = 0;
890
            if (!(chanbias & (1 << i)))
891
                bias = state->bias;
892

    
893
            if (coeff[i]) {
894
                if (blksw[i])
895
                    a52_imdct_256 (samples + 256 * i, samples + 1536 + 256 * i,
896
                                   bias);
897
                else
898
                    a52_imdct_512 (samples + 256 * i, samples + 1536 + 256 * i,
899
                                   bias);
900
            } else {
901
                int j;
902

    
903
                for (j = 0; j < 256; j++)
904
                    (samples + 256 * i)[j] = bias;
905
            }
906
        }
907

    
908
        a52_downmix (samples, state->acmod, state->output, state->bias,
909
                     state->clev, state->slev);
910
    } else {
911
        nfchans = nfchans_tbl[state->output & A52_CHANNEL_MASK];
912

    
913
        a52_downmix (samples, state->acmod, state->output, 0,
914
                     state->clev, state->slev);
915

    
916
        if (!state->downmixed) {
917
            state->downmixed = 1;
918
            a52_downmix (samples + 1536, state->acmod, state->output, 0,
919
                         state->clev, state->slev);
920
        }
921

    
922
        if (blksw[0])
923
            for (i = 0; i < nfchans; i++)
924
                a52_imdct_256 (samples + 256 * i, samples + 1536 + 256 * i,
925
                               state->bias);
926
        else
927
            for (i = 0; i < nfchans; i++)
928
                a52_imdct_512 (samples + 256 * i, samples + 1536 + 256 * i,
929
                               state->bias);
930
    }
931

    
932
    return 0;
933
}
934

    
935
void a52_free (a52_state_t * state)
936
{
937
    free (state->samples);
938
    free (state);
939
}