3 * Copyright (C) 2000-2003 Michel Lespinasse <walken@zoy.org>
4 * Copyright (C) 1999-2000 Aaron Holtzman <aholtzma@ess.engr.uvic.ca>
6 * This file is part of a52dec, a free ATSC A-52 stream decoder.
7 * See http://liba52.sourceforge.net/ for updates.
9 * a52dec is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or
12 * (at your option) any later version.
14 * a52dec is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to the Free Software
21 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
24 #include "a52_internal.h"
25 #include "bitstream.h"
28 #if defined(HAVE_MEMALIGN) && !defined(__cplusplus)
29 /* some systems have memalign() but no declaration for it */
30 void * memalign (size_t align, size_t size);
32 /* assume malloc alignment is sufficient */
33 #define memalign(align,size) malloc (size)
45 static uint8_t halfrate[12] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 2, 3};
47 a52_state_t * a52_init (uint32_t mm_accel)
52 state = (a52_state_t *) malloc (sizeof (a52_state_t));
56 state->samples = (sample_t *) memalign (16, 256 * 12 * sizeof (sample_t));
57 if (state->samples == NULL) {
62 for (i = 0; i < 256 * 12; i++)
63 state->samples[i] = 0;
67 state->lfsr_state = 1;
69 a52_imdct_init (mm_accel);
74 sample_t * a52_samples (a52_state_t * state)
76 return state->samples;
79 int a52_syncinfo (uint8_t * buf, int * flags,
80 int * sample_rate, int * bit_rate)
82 static int rate[] = { 32, 40, 48, 56, 64, 80, 96, 112,
83 128, 160, 192, 224, 256, 320, 384, 448,
85 static uint8_t lfeon[8] = {0x10, 0x10, 0x04, 0x04, 0x04, 0x01, 0x04, 0x01};
91 if ((buf[0] != 0x0b) || (buf[1] != 0x77)) /* syncword */
94 if (buf[5] >= 0x60) /* bsid >= 12 */
96 half = halfrate[buf[5] >> 3];
98 /* acmod, dsurmod and lfeon */
100 *flags = ((((buf[6] & 0xf8) == 0x50) ? A52_DOLBY : acmod) |
101 ((buf[6] & lfeon[acmod]) ? A52_LFE : 0));
103 frmsizecod = buf[4] & 63;
104 if (frmsizecod >= 38)
106 bitrate = rate [frmsizecod >> 1];
107 *bit_rate = (bitrate * 1000) >> half;
109 switch (buf[4] & 0xc0) {
111 *sample_rate = 48000 >> half;
114 *sample_rate = 44100 >> half;
115 return 2 * (320 * bitrate / 147 + (frmsizecod & 1));
117 *sample_rate = 32000 >> half;
124 int a52_frame (a52_state_t * state, uint8_t * buf, int * flags,
125 level_t * level, sample_t bias)
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) };
134 state->fscod = buf[4] >> 6;
135 state->halfrate = halfrate[buf[5] >> 3];
136 state->acmod = acmod = buf[6] >> 5;
138 a52_bitstream_set_ptr (state, buf + 6);
139 bitstream_get (state, 3); /* skip acmod we already parsed */
141 if ((acmod == 2) && (bitstream_get (state, 2) == 2)) /* dsurmod */
144 state->clev = state->slev = 0;
146 if ((acmod & 1) && (acmod != 1))
147 state->clev = clev[bitstream_get (state, 2)]; /* cmixlev */
150 state->slev = slev[bitstream_get (state, 2)]; /* surmixlev */
152 state->lfeon = bitstream_get (state, 1);
154 state->output = a52_downmix_init (acmod, *flags, level,
155 state->clev, state->slev);
156 if (state->output < 0)
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);
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;
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--);
181 bitstream_get (state, 2); /* copyrightb + origbs */
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 */
188 if (bitstream_get (state, 1)) { /* addbsie */
191 addbsil = bitstream_get (state, 6);
193 bitstream_get (state, 8); /* addbsi */
200 void a52_dynrng (a52_state_t * state,
201 level_t (* call) (level_t, void *), void * data)
206 state->dynrngcall = call;
207 state->dynrngdata = data;
211 static int parse_exponents (a52_state_t * state, int expstr, int ngrps,
212 uint8_t exponent, uint8_t * dest)
217 exps = bitstream_get (state, 7);
219 exponent += exp_1[exps];
225 *(dest++) = exponent;
226 *(dest++) = exponent;
228 *(dest++) = exponent;
230 *(dest++) = exponent;
233 exponent += exp_2[exps];
239 *(dest++) = exponent;
240 *(dest++) = exponent;
242 *(dest++) = exponent;
244 *(dest++) = exponent;
247 exponent += exp_3[exps];
253 *(dest++) = exponent;
254 *(dest++) = exponent;
256 *(dest++) = exponent;
258 *(dest++) = exponent;
265 static int parse_deltba (a52_state_t * state, int8_t * deltba)
267 int deltnseg, deltlen, delta, j;
269 memset (deltba, 0, 50);
271 deltnseg = bitstream_get (state, 3);
274 j += bitstream_get (state, 5);
275 deltlen = bitstream_get (state, 4);
276 delta = bitstream_get (state, 3);
277 delta -= (delta >= 4) ? 3 : 4;
280 if (j + deltlen >= 50)
284 } while (deltnseg--);
289 static inline int zero_snr_offsets (int nfchans, a52_state_t * state)
293 if ((state->csnroffst) ||
294 (state->chincpl && state->cplba.bai >> 3) || /* cplinu, fsnroffst */
295 (state->lfeon && state->lfeba.bai >> 3)) /* fsnroffst */
297 for (i = 0; i < nfchans; i++)
298 if (state->ba[i].bai >> 3) /* fsnroffst */
303 static inline int16_t dither_gen (a52_state_t * state)
307 nstate = dither_lut[state->lfsr_state >> 8] ^ (state->lfsr_state << 8);
309 state->lfsr_state = (uint16_t) nstate;
311 return (3 * nstate) >> 2;
315 #define COEFF(c,t,l,s,e) (c) = (t) * (s)[e]
317 #define COEFF(c,_t,_l,s,e) do { \
318 quantizer_t t = (_t); \
321 sample_t tmp = t * (l >> 16) + ((t * (l & 0xffff)) >> 16); \
323 (c) = tmp >> shift; \
325 (c) = tmp << -shift; \
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)
340 for (i = 0; i <= 24; i++)
341 factor[i] = scale_factor[i] * level;
347 for (i = 0; i < end; i++) {
354 COEFF (coeff[i], dither_gen (state), level, factor, exp[i]);
362 if (quant->q1_ptr >= 0) {
363 COEFF (coeff[i], quant->q1[quant->q1_ptr--], level,
369 code = bitstream_get (state, 5);
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]);
379 if (quant->q2_ptr >= 0) {
380 COEFF (coeff[i], quant->q2[quant->q2_ptr--], level,
386 code = bitstream_get (state, 7);
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]);
396 COEFF (coeff[i], q_3[bitstream_get (state, 3)], level,
401 if (quant->q4_ptr == 0) {
403 COEFF (coeff[i], quant->q4, level, factor, exp[i]);
408 code = bitstream_get (state, 7);
411 quant->q4 = q_4_1[code];
412 COEFF (coeff[i], q_4_0[code], level, factor, exp[i]);
417 COEFF (coeff[i], q_5[bitstream_get (state, 4)], level,
422 COEFF (coeff[i], bitstream_get_2 (state, bapi) << (16 - bapi),
423 level, factor, exp[i]);
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])
432 int cplbndstrc, bnd, i, i_end, ch;
437 exp = state->cpl_expbap.exp;
438 bap = state->cpl_expbap.bap;
440 cplbndstrc = state->cplbndstrc;
441 i = state->cplstrtmant;
442 while (i < state->cplendmant) {
444 while (cplbndstrc & 1) {
449 for (ch = 0; ch < nfchans; ch++)
450 cplco[ch] = MUL_L (state->cplco[ch][bnd], coeff[ch]);
454 quantizer_t cplcoeff;
460 for (ch = 0; ch < nfchans; ch++)
461 if ((state->chincpl >> ch) & 1) {
464 samples[ch][i] = (scale_factor[exp[i]] *
465 cplco[ch] * dither_gen (state));
467 COEFF (samples[ch][i], dither_gen (state),
468 cplco[ch], scale_factor, exp[i]);
477 if (quant->q1_ptr >= 0) {
478 cplcoeff = quant->q1[quant->q1_ptr--];
483 code = bitstream_get (state, 5);
486 quant->q1[0] = q_1_2[code];
487 quant->q1[1] = q_1_1[code];
488 cplcoeff = q_1_0[code];
493 if (quant->q2_ptr >= 0) {
494 cplcoeff = quant->q2[quant->q2_ptr--];
499 code = bitstream_get (state, 7);
502 quant->q2[0] = q_2_2[code];
503 quant->q2[1] = q_2_1[code];
504 cplcoeff = q_2_0[code];
509 cplcoeff = q_3[bitstream_get (state, 3)];
513 if (quant->q4_ptr == 0) {
515 cplcoeff = quant->q4;
520 code = bitstream_get (state, 7);
523 quant->q4 = q_4_1[code];
524 cplcoeff = q_4_0[code];
529 cplcoeff = q_5[bitstream_get (state, 4)];
533 cplcoeff = bitstream_get_2 (state, bapi) << (16 - bapi);
536 cplcoeff *= scale_factor[exp[i]];
538 for (ch = 0; ch < nfchans; ch++)
539 if ((state->chincpl >> ch) & 1)
541 samples[ch][i] = cplcoeff * cplco[ch];
543 COEFF (samples[ch][i], cplcoeff, cplco[ch],
544 scale_factor, exp[i]);
551 int a52_block (a52_state_t * state)
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];
560 quantizer_set_t quant;
563 nfchans = nfchans_tbl[state->acmod];
565 for (i = 0; i < nfchans; i++)
566 blksw[i] = bitstream_get (state, 1);
568 for (i = 0; i < nfchans; i++)
569 dithflag[i] = bitstream_get (state, 1);
571 chaninfo = !state->acmod;
573 if (bitstream_get (state, 1)) { /* dynrnge */
576 dynrng = bitstream_get_2 (state, 8);
577 if (state->dynrnge) {
580 #if !defined(LIBA52_FIXED)
581 range = ((((dynrng & 0x1f) | 0x20) << 13) *
582 scale_factor[3 - (dynrng >> 5)]);
584 range = ((dynrng & 0x1f) | 0x20) << (21 + (dynrng >> 5));
586 if (state->dynrngcall)
587 range = state->dynrngcall (range, state->dynrngdata);
588 state->dynrng = MUL_L (state->level, range);
591 } while (chaninfo--);
593 if (bitstream_get (state, 1)) { /* cplstre */
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};
602 for (i = 0; i < nfchans; i++)
603 state->chincpl |= bitstream_get (state, 1) << i;
604 switch (state->acmod) {
608 state->phsflginu = bitstream_get (state, 1);
610 cplbegf = bitstream_get (state, 4);
611 cplendf = bitstream_get (state, 4);
613 if (cplendf + 3 - cplbegf < 0)
615 state->ncplbnd = ncplsubnd = cplendf + 3 - cplbegf;
616 state->cplstrtbnd = bndtab[cplbegf];
617 state->cplstrtmant = cplbegf * 12 + 37;
618 state->cplendmant = cplendf * 12 + 73;
620 state->cplbndstrc = 0;
621 for (i = 0; i < ncplsubnd - 1; i++)
622 if (bitstream_get (state, 1)) {
623 state->cplbndstrc |= 1 << i;
629 if (state->chincpl) { /* cplinu */
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;
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);
646 cplcomant = (cplcomant | 0x10) << 13;
649 cplcomant * scale_factor[cplcoexp + mstrcplco];
651 state->cplco[i][j] = (cplcomant << 11) >> (cplcoexp + mstrcplco);
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];
662 if ((state->acmod == 2) && (bitstream_get (state, 1))) { /* rematstr */
666 end = (state->chincpl) ? state->cplstrtmant : 253; /* cplinu */
669 state->rematflg |= bitstream_get (state, 1) << i;
670 while (rematrix_band[i++] < end);
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);
680 lfeexpstr = bitstream_get (state, 1);
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;
689 chbwcod = bitstream_get (state, 6);
692 state->endmant[i] = chbwcod * 3 + 73;
698 if (cplexpstr != EXP_REUSE) {
699 int cplabsexp, ncplgrps;
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))
709 for (i = 0; i < nfchans; i++)
710 if (chexpstr[i] != EXP_REUSE) {
711 int grp_size, nchgrps;
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))
721 bitstream_get (state, 2); /* gainrng */
723 if (lfeexpstr != EXP_REUSE) {
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))
731 if (bitstream_get (state, 1)) { /* baie */
733 state->bai = bitstream_get (state, 11);
735 if (bitstream_get (state, 1)) { /* snroffste */
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);
743 state->lfeba.bai = bitstream_get (state, 7);
745 if ((state->chincpl) && (bitstream_get (state, 1))) { /* cplleake */
747 state->cplfleak = 9 - bitstream_get (state, 3);
748 state->cplsleak = 9 - bitstream_get (state, 3);
751 if (bitstream_get (state, 1)) { /* deltbaie */
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))
761 for (i = 0; i < nfchans; i++)
762 if ((state->ba[i].deltbae == DELTA_BIT_NEW) &&
763 parse_deltba (state, state->ba[i].deltba))
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));
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,
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,
793 if (bitstream_get (state, 1)) { /* skiple */
794 i = bitstream_get (state, 9); /* skipl */
796 bitstream_get (state, 8);
799 samples = state->samples;
800 if (state->output & A52_LFE)
801 samples += 256; /* shift for LFE channel */
803 chanbias = a52_downmix_coeff (coeff, state->acmod, state->output,
804 state->dynrng, state->clev, state->slev);
806 quant.q1_ptr = quant.q2_ptr = quant.q4_ptr = -1;
809 for (i = 0; i < nfchans; i++) {
812 coeff_get (state, samples + 256 * i, state->fbw_expbap +i, &quant,
813 coeff[i], dithflag[i], state->endmant[i]);
815 if ((state->chincpl >> i) & 1) {
818 coeff_get_coupling (state, nfchans, coeff,
819 (sample_t (*)[256])samples, &quant,
822 j = state->cplendmant;
824 j = state->endmant[i];
826 (samples + 256 * i)[j] = 0;
830 if (state->acmod == 2) {
831 int j, end, band, rematflg;
833 end = ((state->endmant[0] < state->endmant[1]) ?
834 state->endmant[0] : state->endmant[1]);
838 rematflg = state->rematflg;
840 if (! (rematflg & 1)) {
842 j = rematrix_band[i++];
846 band = rematrix_band[i++];
853 tmp1 = (samples+256)[j];
854 samples[j] = tmp0 + tmp1;
855 (samples+256)[j] = tmp0 - tmp1;
856 } while (++j < band);
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);
868 /* just skip the LFE coefficients */
869 coeff_get (state, samples + 1280, &state->lfe_expbap, &quant,
875 if (nfchans_tbl[state->output & A52_CHANNEL_MASK] < nfchans)
876 for (i = 1; i < nfchans; i++)
877 if (blksw[i] != blksw[0])
881 if (state->downmixed) {
882 state->downmixed = 0;
883 a52_upmix (samples + 1536, state->acmod, state->output);
886 for (i = 0; i < nfchans; i++) {
890 if (!(chanbias & (1 << i)))
895 a52_imdct_256 (samples + 256 * i, samples + 1536 + 256 * i,
898 a52_imdct_512 (samples + 256 * i, samples + 1536 + 256 * i,
903 for (j = 0; j < 256; j++)
904 (samples + 256 * i)[j] = bias;
908 a52_downmix (samples, state->acmod, state->output, state->bias,
909 state->clev, state->slev);
911 nfchans = nfchans_tbl[state->output & A52_CHANNEL_MASK];
913 a52_downmix (samples, state->acmod, state->output, 0,
914 state->clev, state->slev);
916 if (!state->downmixed) {
917 state->downmixed = 1;
918 a52_downmix (samples + 1536, state->acmod, state->output, 0,
919 state->clev, state->slev);
923 for (i = 0; i < nfchans; i++)
924 a52_imdct_256 (samples + 256 * i, samples + 1536 + 256 * i,
927 for (i = 0; i < nfchans; i++)
928 a52_imdct_512 (samples + 256 * i, samples + 1536 + 256 * i,
935 void a52_free (a52_state_t * state)
937 free (state->samples);