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-rw-r--r--src/libac3/parse.c689
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diff --git a/src/libac3/parse.c b/src/libac3/parse.c
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--- a/src/libac3/parse.c
+++ /dev/null
@@ -1,689 +0,0 @@
-/*
- * parse.c
- *
- * Copyright (C) Aaron Holtzman - May 1999
- *
- * This file is part of ac3dec, a free Dolby AC-3 stream decoder.
- *
- * ac3dec is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2, or (at your option)
- * any later version.
- *
- * ac3dec is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with GNU Make; see the file COPYING. If not, write to
- * the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
- *
- *
- */
-
-#include "config.h"
-
-#include <inttypes.h>
-#include <string.h>
-
-#include "ac3.h"
-#include "ac3_internal.h"
-#include "bitstream.h"
-#include "tables.h"
-
-void ac3_init (void)
-{
- imdct_init ();
-}
-
-static uint8_t halfrate[12] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 2, 3};
-
-int ac3_syncinfo (uint8_t * buf, int * flags,
- int * sample_rate, int * bit_rate)
-{
- static int rate[] = { 32, 40, 48, 56, 64, 80, 96, 112,
- 128, 160, 192, 224, 256, 320, 384, 448,
- 512, 576, 640};
- static uint8_t lfeon[8] = {0x10, 0x10, 0x04, 0x04, 0x04, 0x01, 0x04, 0x01};
- int frmsizecod;
- int bitrate;
- int half;
- int acmod;
-
- if ((buf[0] != 0x0b) || (buf[1] != 0x77)) // syncword
- return 0;
-
- if (buf[5] >= 0x60) // bsid >= 12
- return 0;
- half = halfrate[buf[5] >> 3];
-
- // acmod, dsurmod and lfeon
- acmod = buf[6] >> 5;
- *flags = ((((buf[6] & 0xf8) == 0x50) ? AC3_DOLBY : acmod) |
- ((buf[6] & lfeon[acmod]) ? AC3_LFE : 0));
-
- frmsizecod = buf[4] & 63;
- if (frmsizecod >= 38)
- return 0;
- bitrate = rate [frmsizecod >> 1];
- *bit_rate = (bitrate * 1000) >> half;
-
- switch (buf[4] & 0xc0) {
- case 0: // 48 KHz
- *sample_rate = 48000 >> half;
- return 4 * bitrate;
- case 0x40:
- *sample_rate = 44100 >> half;
- return 2 * (320 * bitrate / 147 + (frmsizecod & 1));
- case 0x80:
- *sample_rate = 32000 >> half;
- return 6 * bitrate;
- default:
- return 0;
- }
-}
-
-int ac3_frame (ac3_state_t * state, uint8_t * buf, int * flags,
- sample_t * level, sample_t bias, sample_t * delay)
-{
- static sample_t clev[4] = {LEVEL_3DB, LEVEL_45DB, LEVEL_6DB, LEVEL_45DB};
- static sample_t slev[4] = {LEVEL_3DB, LEVEL_6DB, 0, LEVEL_6DB};
- int chaninfo;
- int acmod;
-
- state->fscod = buf[4] >> 6;
- state->halfrate = halfrate[buf[5] >> 3];
- state->acmod = acmod = buf[6] >> 5;
-
- bitstream_set_ptr (buf + 6);
- bitstream_get (3); // skip acmod we already parsed
-
- if ((acmod == 2) && (bitstream_get (2) == 2)) // dsurmod
- acmod = AC3_DOLBY;
-
- if ((acmod & 1) && (acmod != 1))
- state->clev = clev[bitstream_get (2)]; // cmixlev
-
- if (acmod & 4)
- state->slev = slev[bitstream_get (2)]; // surmixlev
-
- state->lfeon = bitstream_get (1);
-
- state->output = downmix_init (acmod, *flags, level,
- state->clev, state->slev);
- if (state->output < 0)
- return 1;
- if (state->lfeon && (*flags & AC3_LFE)) {
- state->output |= AC3_LFE;
- delay += 256;
- }
- *flags = state->output;
- state->level = *level;
- state->bias = bias;
- state->delay = delay;
-
- chaninfo = !acmod;
- do {
- bitstream_get (5); // dialnorm
- if (bitstream_get (1)) // compre
- bitstream_get (8); // compr
- if (bitstream_get (1)) // langcode
- bitstream_get (8); // langcod
- if (bitstream_get (1)) // audprodie
- bitstream_get (7); // mixlevel + roomtyp
- } while (chaninfo--);
-
- bitstream_get (2); // copyrightb + origbs
-
- if (bitstream_get (1)) // timecod1e
- bitstream_get (14); // timecod1
- if (bitstream_get (1)) // timecod2e
- bitstream_get (14); // timecod2
-
- if (bitstream_get (1)) { // addbsie
- int addbsil;
-
- addbsil = bitstream_get (6);
- do {
- bitstream_get (8); // addbsi
- } while (addbsil--);
- }
-
- return 0;
-}
-
-static int parse_exponents (int expstr, int ngrps, uint8_t exponent,
- uint8_t * dest)
-{
- int exps;
-
- while (ngrps--) {
- exps = bitstream_get (7);
-
- exponent += exp_1[exps];
- if (exponent > 24)
- return 1;
-
- switch (expstr) {
- case EXP_D45:
- *(dest++) = exponent;
- *(dest++) = exponent;
- case EXP_D25:
- *(dest++) = exponent;
- case EXP_D15:
- *(dest++) = exponent;
- }
-
- exponent += exp_2[exps];
- if (exponent > 24)
- return 1;
-
- switch (expstr) {
- case EXP_D45:
- *(dest++) = exponent;
- *(dest++) = exponent;
- case EXP_D25:
- *(dest++) = exponent;
- case EXP_D15:
- *(dest++) = exponent;
- }
-
- exponent += exp_3[exps];
- if (exponent > 24)
- return 1;
-
- switch (expstr) {
- case EXP_D45:
- *(dest++) = exponent;
- *(dest++) = exponent;
- case EXP_D25:
- *(dest++) = exponent;
- case EXP_D15:
- *(dest++) = exponent;
- }
- }
-
- return 0;
-}
-
-static int parse_deltba (int8_t * deltba)
-{
- int deltnseg, deltlen, delta, j;
-
- memset (deltba, 0, 50);
-
- deltnseg = bitstream_get (3);
- j = 0;
- do {
- j += bitstream_get (5);
- deltlen = bitstream_get (4);
- delta = bitstream_get (3);
- delta -= (delta >= 4) ? 3 : 4;
- if (!deltlen)
- continue;
- if (j + deltlen >= 50)
- return 1;
- while (deltlen--)
- deltba[j++] = delta;
- } while (deltnseg--);
-
- return 0;
-}
-
-static inline int zero_snr_offsets (int nfchans, ac3_state_t * state)
-{
- int i;
-
- if ((state->csnroffst) || (state->cplinu && state->cplba.fsnroffst) ||
- (state->lfeon && state->lfeba.fsnroffst))
- return 0;
- for (i = 0; i < nfchans; i++)
- if (state->ba[i].fsnroffst)
- return 0;
- return 1;
-}
-
-static sample_t q_1[2];
-static sample_t q_2[2];
-static sample_t q_4;
-static int q_1_pointer;
-static int q_2_pointer;
-static int q_4_pointer;
-
-#define GET_COEFF(COEFF,DITHER) \
- switch (bap[i]) { \
- case 0: \
- DITHER (scale_factor[exp[i]]); \
- \
- case -1: \
- if (q_1_pointer >= 0) { \
- COEFF (q_1[q_1_pointer--] * scale_factor[exp[i]]); \
- } else { \
- int code; \
- \
- code = bitstream_get (5); \
- \
- q_1_pointer = 1; \
- q_1[0] = q_1_2[code]; \
- q_1[1] = q_1_1[code]; \
- COEFF (q_1_0[code] * scale_factor[exp[i]]); \
- } \
- \
- case -2: \
- if (q_2_pointer >= 0) { \
- COEFF (q_2[q_2_pointer--] * scale_factor[exp[i]]); \
- } else { \
- int code; \
- \
- code = bitstream_get (7); \
- \
- q_2_pointer = 1; \
- q_2[0] = q_2_2[code]; \
- q_2[1] = q_2_1[code]; \
- COEFF (q_2_0[code] * scale_factor[exp[i]]); \
- } \
- \
- case 3: \
- COEFF (q_3[bitstream_get (3)] * scale_factor[exp[i]]); \
- \
- case -3: \
- if (q_4_pointer == 0) { \
- q_4_pointer = -1; \
- COEFF (q_4 * scale_factor[exp[i]]); \
- } else { \
- int code; \
- \
- code = bitstream_get (7); \
- \
- q_4_pointer = 0; \
- q_4 = q_4_1[code]; \
- COEFF (q_4_0[code] * scale_factor[exp[i]]); \
- } \
- \
- case 4: \
- COEFF (q_5[bitstream_get (4)] * scale_factor[exp[i]]); \
- \
- default: \
- COEFF (((int16_t)(bitstream_get(bap[i]) << (16 - bap[i]))) * \
- scale_factor[exp[i]]); \
- }
-
-#define CHANNEL_COEFF(val) \
- coeff[i] = val; \
- i++; \
- continue;
-
-#define CHANNEL_DITHER(val) \
- if (dither) { \
- coeff[i] = dither_gen () * val; \
- i++; \
- continue; \
- } else { \
- coeff[i] = 0; \
- i++; \
- continue; \
- }
-
-static uint16_t lfsr_state = 1;
-
-static inline int16_t dither_gen(void)
-{
- int16_t state;
-
- state = dither_lut[lfsr_state >> 8] ^ (lfsr_state << 8);
-
- lfsr_state = (uint16_t) state;
-
- return ((state * (int) (LEVEL_3DB * 256)) >> 8);
-}
-
-static void coeff_get (sample_t * coeff, uint8_t * exp, int8_t * bap,
- int dither, int end)
-{
- int i;
-
- i = 0;
- while (i < end)
- GET_COEFF (CHANNEL_COEFF, CHANNEL_DITHER);
-}
-
-#define COUPLING_COEFF(val) \
- cplcoeff = val; \
- break;
-
-#define COUPLING_DITHER(val) \
- cplcoeff = val; \
- for (ch = 0; ch < nfchans; ch++) \
- if (state->chincpl[ch]) { \
- if (dithflag[ch]) \
- samples[ch][i] = \
- state->cplco[ch][bnd] * dither_gen () * cplcoeff; \
- else \
- samples[ch][i] = 0; \
- } \
- i++; \
- continue;
-
-int ac3_block (ac3_state_t * state, sample_t samples[][256])
-{
- static const uint8_t nfchans_tbl[8] = {2, 1, 2, 3, 3, 4, 4, 5};
- static int rematrix_band[4] = {25, 37, 61, 253};
- int i, nfchans, chaninfo;
- uint8_t cplexpstr, chexpstr[5], lfeexpstr, do_bit_alloc, done_cpl;
- uint8_t blksw[5], dithflag[5];
-
- nfchans = nfchans_tbl[state->acmod];
-
- for (i = 0; i < nfchans; i++)
- blksw[i] = bitstream_get (1);
-
- for (i = 0; i < nfchans; i++)
- dithflag[i] = bitstream_get (1);
-
- chaninfo = !(state->acmod);
- do {
- if (bitstream_get (1)) // dynrnge
- bitstream_get (8); // dynrng
- } while (chaninfo--);
-
- if (bitstream_get (1)) { // cplstre
- state->cplinu = bitstream_get (1);
- if (state->cplinu) {
- static int bndtab[16] = {31, 35, 37, 39, 41, 42, 43, 44,
- 45, 45, 46, 46, 47, 47, 48, 48};
- int cplbegf;
- int cplendf;
- int ncplsubnd;
-
- for (i = 0; i < nfchans; i++)
- state->chincpl[i] = bitstream_get (1);
- switch (state->acmod) {
- case 0: case 1:
- return 1;
- case 2:
- state->phsflginu = bitstream_get (1);
- }
- cplbegf = bitstream_get (4);
- cplendf = bitstream_get (4);
-
- if (cplendf + 3 - cplbegf < 0)
- return 1;
- state->ncplbnd = ncplsubnd = cplendf + 3 - cplbegf;
- state->cplstrtbnd = bndtab[cplbegf];
- state->cplstrtmant = cplbegf * 12 + 37;
- state->cplendmant = cplendf * 12 + 73;
-
- for (i = 0; i < ncplsubnd - 1; i++) {
- state->cplbndstrc[i] = bitstream_get (1);
- state->ncplbnd -= state->cplbndstrc[i];
- }
- state->cplbndstrc[i] = 0; // last value is a sentinel
- }
- }
-
- if (state->cplinu) {
- int j, cplcoe;
-
- cplcoe = 0;
- for (i = 0; i < nfchans; i++)
- if (state->chincpl[i])
- if (bitstream_get (1)) { // cplcoe
- int mstrcplco, cplcoexp, cplcomant;
-
- cplcoe = 1;
- mstrcplco = 3 * bitstream_get (2);
- for (j = 0; j < state->ncplbnd; j++) {
- cplcoexp = bitstream_get (4);
- cplcomant = bitstream_get (4);
- if (cplcoexp == 15)
- cplcomant <<= 14;
- else
- cplcomant = (cplcomant | 0x10) << 13;
- state->cplco[i][j] =
- cplcomant * scale_factor[cplcoexp + mstrcplco];
- }
- }
- if ((state->acmod == 2) && state->phsflginu && cplcoe)
- for (j = 0; j < state->ncplbnd; j++)
- if (bitstream_get (1)) // phsflg
- state->cplco[1][j] = -state->cplco[1][j];
- }
-
- if ((state->acmod == 2) && (bitstream_get (1))) { // rematstr
- int end;
-
- end = (state->cplinu) ? state->cplstrtmant : 253;
- i = 0;
- do
- state->rematflg[i] = bitstream_get (1);
- while (rematrix_band[i++] < end);
- }
-
- cplexpstr = EXP_REUSE;
- lfeexpstr = EXP_REUSE;
- if (state->cplinu)
- cplexpstr = bitstream_get (2);
- for (i = 0; i < nfchans; i++)
- chexpstr[i] = bitstream_get (2);
- if (state->lfeon)
- lfeexpstr = bitstream_get (1);
-
- for (i = 0; i < nfchans; i++)
- if (chexpstr[i] != EXP_REUSE) {
- if (state->cplinu && state->chincpl[i])
- state->endmant[i] = state->cplstrtmant;
- else {
- int chbwcod;
-
- chbwcod = bitstream_get (6);
- if (chbwcod > 60)
- return 1;
- state->endmant[i] = chbwcod * 3 + 73;
- }
- }
-
- do_bit_alloc = 0;
-
- if (cplexpstr != EXP_REUSE) {
- int cplabsexp, ncplgrps;
-
- do_bit_alloc = 1;
- ncplgrps = ((state->cplendmant - state->cplstrtmant) /
- (3 << (cplexpstr - 1)));
- cplabsexp = bitstream_get (4) << 1;
- if (parse_exponents (cplexpstr, ncplgrps, cplabsexp,
- state->cpl_exp + state->cplstrtmant))
- return 1;
- }
- for (i = 0; i < nfchans; i++)
- if (chexpstr[i] != EXP_REUSE) {
- int grp_size, nchgrps;
-
- do_bit_alloc = 1;
- grp_size = 3 << (chexpstr[i] - 1);
- nchgrps = (state->endmant[i] + grp_size - 4) / grp_size;
- state->fbw_exp[i][0] = bitstream_get (4);
- if (parse_exponents (chexpstr[i], nchgrps, state->fbw_exp[i][0],
- state->fbw_exp[i] + 1))
- return 1;
- bitstream_get (2); // gainrng
- }
- if (lfeexpstr != EXP_REUSE) {
- do_bit_alloc = 1;
- state->lfe_exp[0] = bitstream_get (4);
- if (parse_exponents (lfeexpstr, 2, state->lfe_exp[0],
- state->lfe_exp + 1))
- return 1;
- }
-
- if (bitstream_get (1)) { // baie
- do_bit_alloc = 1;
- state->sdcycod = bitstream_get (2);
- state->fdcycod = bitstream_get (2);
- state->sgaincod = bitstream_get (2);
- state->dbpbcod = bitstream_get (2);
- state->floorcod = bitstream_get (3);
- }
- if (bitstream_get (1)) { //snroffste
- do_bit_alloc = 1;
- state->csnroffst = bitstream_get (6);
- if (state->cplinu) {
- state->cplba.fsnroffst = bitstream_get (4);
- state->cplba.fgaincod = bitstream_get (3);
- }
- for (i = 0; i < nfchans; i++) {
- state->ba[i].fsnroffst = bitstream_get (4);
- state->ba[i].fgaincod = bitstream_get (3);
- }
- if (state->lfeon) {
- state->lfeba.fsnroffst = bitstream_get (4);
- state->lfeba.fgaincod = bitstream_get (3);
- }
- }
- if ((state->cplinu) && (bitstream_get (1))) { // cplleake
- do_bit_alloc = 1;
- state->cplfleak = 2304 - (bitstream_get (3) << 8);
- state->cplsleak = 2304 - (bitstream_get (3) << 8);
- }
-
- if (bitstream_get (1)) { // deltbaie
- do_bit_alloc = 1;
- if (state->cplinu)
- state->cplba.deltbae = bitstream_get (2);
- for (i = 0; i < nfchans; i++)
- state->ba[i].deltbae = bitstream_get (2);
- if (state->cplinu && (state->cplba.deltbae == DELTA_BIT_NEW) &&
- parse_deltba (state->cplba.deltba))
- return 1;
- for (i = 0; i < nfchans; i++)
- if ((state->ba[i].deltbae == DELTA_BIT_NEW) &&
- parse_deltba (state->ba[i].deltba))
- return 1;
- }
-
- if (do_bit_alloc) {
- if (zero_snr_offsets (nfchans, state)) {
- memset (state->cpl_bap, 0, sizeof (state->cpl_bap));
- memset (state->fbw_bap, 0, sizeof (state->fbw_bap));
- memset (state->lfe_bap, 0, sizeof (state->lfe_bap));
- } else {
- if (state->cplinu)
- bit_allocate (state, &state->cplba, state->cplstrtbnd,
- state->cplstrtmant, state->cplendmant,
- state->cplfleak, state->cplsleak,
- state->cpl_exp, state->cpl_bap);
- for (i = 0; i < nfchans; i++)
- bit_allocate (state, state->ba + i, 0, 0, state->endmant[i],
- 0, 0, state->fbw_exp[i], state->fbw_bap[i]);
- if (state->lfeon) {
- state->lfeba.deltbae = DELTA_BIT_NONE;
- bit_allocate (state, &state->lfeba, 0, 0, 7, 0, 0,
- state->lfe_exp, state->lfe_bap);
- }
- }
- }
-
- if (bitstream_get (1)) { // skiple
- i = bitstream_get (9); // skipl
- while (i--)
- bitstream_get (8);
- }
-
- if (state->output & AC3_LFE)
- samples++; // shift for LFE channel
-
- q_1_pointer = q_2_pointer = q_4_pointer = -1;
- done_cpl = 0;
-
- for (i = 0; i < nfchans; i++) {
- int j;
-
- coeff_get (samples[i], state->fbw_exp[i], state->fbw_bap[i],
- dithflag[i], state->endmant[i]);
-
- if (state->cplinu && state->chincpl[i]) {
- if (!done_cpl) {
- int i, i_end, bnd, sub_bnd, ch;
- sample_t cplcoeff;
-
- done_cpl = 1;
-
-#define bap state->cpl_bap
-#define exp state->cpl_exp
-
- sub_bnd = bnd = 0;
- i = state->cplstrtmant;
- while (i < state->cplendmant) {
- i_end = i + 12;
- while (state->cplbndstrc[sub_bnd++])
- i_end += 12;
-
- while (i < i_end) {
- GET_COEFF (COUPLING_COEFF, COUPLING_DITHER);
- for (ch = 0; ch < nfchans; ch++)
- if (state->chincpl[ch])
- samples[ch][i] =
- state->cplco[ch][bnd] * cplcoeff;
- i++;
- }
- bnd++;
- }
-
-#undef bap
-#undef exp
- }
- j = state->cplendmant;
- } else
- j = state->endmant[i];
- for (; j < 256; j++)
- samples[i][j] = 0;
- }
-
- if (state->acmod == 2) {
- int j, end, band;
-
- end = ((state->endmant[0] < state->endmant[1]) ?
- state->endmant[0] : state->endmant[1]);
-
- i = 0;
- j = 13;
- do {
- if (!state->rematflg[i]) {
- j = rematrix_band[i++];
- continue;
- }
- band = rematrix_band[i++];
- if (band > end)
- band = end;
- do {
- sample_t tmp0, tmp1;
-
- tmp0 = samples[0][j];
- tmp1 = samples[1][j];
- samples[0][j] = tmp0 + tmp1;
- samples[1][j] = tmp0 - tmp1;
- } while (++j < band);
- } while (j < end);
- }
-
- if (state->lfeon) {
- coeff_get (samples[-1], state->lfe_exp, state->lfe_bap, 0, 7);
- if (state->output & AC3_LFE) {
- for (i = 7; i < 256; i++)
- samples[-1][i] = 0;
- imdct_512 (samples[-1], state->delay - 256);
- }
- }
-
- for (i = 0; i < nfchans; i++)
- if (blksw[i])
- imdct_256 (samples[i], state->delay + i * 256);
- else
- imdct_512 (samples[i], state->delay + i * 256);
-
- downmix (*samples, state->acmod, state->output, state->level, state->bias,
- state->clev, state->slev);
-
- return 0;
-}
generated by cgit v1.2.3 (git 2.25.1) at 2025-04-28 19:44:42 +0000