+++ /dev/null
-/*
- * bit_allocate.c
- * Copyright (C) 2000-2002 Michel Lespinasse <walken@zoy.org>
- * Copyright (C) 1999-2000 Aaron Holtzman <aholtzma@ess.engr.uvic.ca>
- *
- * This file is part of a52dec, a free ATSC A-52 stream decoder.
- * See http://liba52.sourceforge.net/ for updates.
- *
- * a52dec 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 of the License, or
- * (at your option) any later version.
- *
- * a52dec 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 this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
- */
-
-#include "config.h"
-
-#include <inttypes.h>
-
-#include "a52.h"
-#include "a52_internal.h"
-
-static int hthtab[3][50] = {
- {0x730, 0x730, 0x7c0, 0x800, 0x820, 0x840, 0x850, 0x850, 0x860, 0x860,
- 0x860, 0x860, 0x860, 0x870, 0x870, 0x870, 0x880, 0x880, 0x890, 0x890,
- 0x8a0, 0x8a0, 0x8b0, 0x8b0, 0x8c0, 0x8c0, 0x8d0, 0x8e0, 0x8f0, 0x900,
- 0x910, 0x910, 0x910, 0x910, 0x900, 0x8f0, 0x8c0, 0x870, 0x820, 0x7e0,
- 0x7a0, 0x770, 0x760, 0x7a0, 0x7c0, 0x7c0, 0x6e0, 0x400, 0x3c0, 0x3c0},
- {0x710, 0x710, 0x7a0, 0x7f0, 0x820, 0x830, 0x840, 0x850, 0x850, 0x860,
- 0x860, 0x860, 0x860, 0x860, 0x870, 0x870, 0x870, 0x880, 0x880, 0x880,
- 0x890, 0x890, 0x8a0, 0x8a0, 0x8b0, 0x8b0, 0x8c0, 0x8c0, 0x8e0, 0x8f0,
- 0x900, 0x910, 0x910, 0x910, 0x910, 0x900, 0x8e0, 0x8b0, 0x870, 0x820,
- 0x7e0, 0x7b0, 0x760, 0x770, 0x7a0, 0x7c0, 0x780, 0x5d0, 0x3c0, 0x3c0},
- {0x680, 0x680, 0x750, 0x7b0, 0x7e0, 0x810, 0x820, 0x830, 0x840, 0x850,
- 0x850, 0x850, 0x860, 0x860, 0x860, 0x860, 0x860, 0x860, 0x860, 0x860,
- 0x870, 0x870, 0x870, 0x870, 0x880, 0x880, 0x880, 0x890, 0x8a0, 0x8b0,
- 0x8c0, 0x8d0, 0x8e0, 0x8f0, 0x900, 0x910, 0x910, 0x910, 0x900, 0x8f0,
- 0x8d0, 0x8b0, 0x840, 0x7f0, 0x790, 0x760, 0x7a0, 0x7c0, 0x7b0, 0x720}
-};
-
-static int8_t baptab[305] = {
- 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16,
- 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16,
- 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16,
- 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16,
- 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16,
- 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, /* 93 padding elems */
-
- 16, 16, 16, 16, 16, 16, 16, 16, 16, 14, 14, 14, 14, 14, 14, 14,
- 14, 12, 12, 12, 12, 11, 11, 11, 11, 10, 10, 10, 10, 9, 9, 9,
- 9, 8, 8, 8, 8, 7, 7, 7, 7, 6, 6, 6, 6, 5, 5, 5,
- 5, 4, 4, -3, -3, 3, 3, 3, -2, -2, -1, -1, -1, -1, -1, 0,
-
- 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
- 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
- 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
- 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
- 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
- 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
- 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
- 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
- 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
- 0, 0, 0, 0 /* 148 padding elems */
-};
-
-static int bndtab[30] = {21, 22, 23, 24, 25, 26, 27, 28, 31, 34,
- 37, 40, 43, 46, 49, 55, 61, 67, 73, 79,
- 85, 97, 109, 121, 133, 157, 181, 205, 229, 253};
-
-static int8_t latab[256] = {
- -64, -63, -62, -61, -60, -59, -58, -57, -56, -55, -54, -53,
- -52, -52, -51, -50, -49, -48, -47, -47, -46, -45, -44, -44,
- -43, -42, -41, -41, -40, -39, -38, -38, -37, -36, -36, -35,
- -35, -34, -33, -33, -32, -32, -31, -30, -30, -29, -29, -28,
- -28, -27, -27, -26, -26, -25, -25, -24, -24, -23, -23, -22,
- -22, -21, -21, -21, -20, -20, -19, -19, -19, -18, -18, -18,
- -17, -17, -17, -16, -16, -16, -15, -15, -15, -14, -14, -14,
- -13, -13, -13, -13, -12, -12, -12, -12, -11, -11, -11, -11,
- -10, -10, -10, -10, -10, -9, -9, -9, -9, -9, -8, -8,
- -8, -8, -8, -8, -7, -7, -7, -7, -7, -7, -6, -6,
- -6, -6, -6, -6, -6, -6, -5, -5, -5, -5, -5, -5,
- -5, -5, -4, -4, -4, -4, -4, -4, -4, -4, -4, -4,
- -4, -3, -3, -3, -3, -3, -3, -3, -3, -3, -3, -3,
- -3, -3, -3, -2, -2, -2, -2, -2, -2, -2, -2, -2,
- -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -1, -1,
- -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
- -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
- -1, -1, -1, -1, -1, -1, 0, 0, 0, 0, 0, 0,
- 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
- 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
- 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
- 0, 0, 0, 0
-};
-
-#define UPDATE_LEAK() \
-do { \
- fastleak += fdecay; \
- if (fastleak > psd + fgain) \
- fastleak = psd + fgain; \
- slowleak += sdecay; \
- if (slowleak > psd + sgain) \
- slowleak = psd + sgain; \
-} while (0)
-
-#define COMPUTE_MASK() \
-do { \
- if (psd > dbknee) \
- mask -= (psd - dbknee) >> 2; \
- if (mask > hth [i >> halfrate]) \
- mask = hth [i >> halfrate]; \
- mask -= snroffset + 128 * deltba[i]; \
- mask = (mask > 0) ? 0 : ((-mask) >> 5); \
- mask -= floor; \
-} while (0)
-
-void a52_bit_allocate (a52_state_t * state, ba_t * ba, int bndstart,
- int start, int end, int fastleak, int slowleak,
- expbap_t * expbap)
-{
- static int slowgain[4] = {0x540, 0x4d8, 0x478, 0x410};
- static int dbpbtab[4] = {0xc00, 0x500, 0x300, 0x100};
- static int floortab[8] = {0x910, 0x950, 0x990, 0x9d0,
- 0xa10, 0xa90, 0xb10, 0x1400};
-
- int i, j;
- uint8_t * exp;
- int8_t * bap;
- int fdecay, fgain, sdecay, sgain, dbknee, floor, snroffset;
- int psd, mask;
- int8_t * deltba;
- int * hth;
- int halfrate;
-
- halfrate = state->halfrate;
- fdecay = (63 + 20 * ((state->bai >> 7) & 3)) >> halfrate; /* fdcycod */
- fgain = 128 + 128 * (ba->bai & 7); /* fgaincod */
- sdecay = (15 + 2 * (state->bai >> 9)) >> halfrate; /* sdcycod */
- sgain = slowgain[(state->bai >> 5) & 3]; /* sgaincod */
- dbknee = dbpbtab[(state->bai >> 3) & 3]; /* dbpbcod */
- hth = hthtab[state->fscod];
- /*
- * if there is no delta bit allocation, make deltba point to an area
- * known to contain zeroes. baptab+156 here.
- */
- deltba = (ba->deltbae == DELTA_BIT_NONE) ? baptab + 156 : ba->deltba;
- floor = floortab[state->bai & 7]; /* floorcod */
- snroffset = 960 - 64 * state->csnroffst - 4 * (ba->bai >> 3) + floor;
- floor >>= 5;
-
- exp = expbap->exp;
- bap = expbap->bap;
-
- i = bndstart;
- j = start;
- if (start == 0) { /* not the coupling channel */
- int lowcomp;
-
- lowcomp = 0;
- j = end - 1;
- do {
- if (i < j) {
- if (exp[i+1] == exp[i] - 2)
- lowcomp = 384;
- else if (lowcomp && (exp[i+1] > exp[i]))
- lowcomp -= 64;
- }
- psd = 128 * exp[i];
- mask = psd + fgain + lowcomp;
- COMPUTE_MASK ();
- bap[i] = (baptab+156)[mask + 4 * exp[i]];
- i++;
- } while ((i < 3) || ((i < 7) && (exp[i] > exp[i-1])));
- fastleak = psd + fgain;
- slowleak = psd + sgain;
-
- while (i < 7) {
- if (i < j) {
- if (exp[i+1] == exp[i] - 2)
- lowcomp = 384;
- else if (lowcomp && (exp[i+1] > exp[i]))
- lowcomp -= 64;
- }
- psd = 128 * exp[i];
- UPDATE_LEAK ();
- mask = ((fastleak + lowcomp < slowleak) ?
- fastleak + lowcomp : slowleak);
- COMPUTE_MASK ();
- bap[i] = (baptab+156)[mask + 4 * exp[i]];
- i++;
- }
-
- if (end == 7) /* lfe channel */
- return;
-
- do {
- if (exp[i+1] == exp[i] - 2)
- lowcomp = 320;
- else if (lowcomp && (exp[i+1] > exp[i]))
- lowcomp -= 64;
- psd = 128 * exp[i];
- UPDATE_LEAK ();
- mask = ((fastleak + lowcomp < slowleak) ?
- fastleak + lowcomp : slowleak);
- COMPUTE_MASK ();
- bap[i] = (baptab+156)[mask + 4 * exp[i]];
- i++;
- } while (i < 20);
-
- while (lowcomp > 128) { /* two iterations maximum */
- lowcomp -= 128;
- psd = 128 * exp[i];
- UPDATE_LEAK ();
- mask = ((fastleak + lowcomp < slowleak) ?
- fastleak + lowcomp : slowleak);
- COMPUTE_MASK ();
- bap[i] = (baptab+156)[mask + 4 * exp[i]];
- i++;
- }
- j = i;
- }
-
- do {
- int startband, endband;
-
- startband = j;
- endband = ((bndtab-20)[i] < end) ? (bndtab-20)[i] : end;
- psd = 128 * exp[j++];
- while (j < endband) {
- int next, delta;
-
- next = 128 * exp[j++];
- delta = next - psd;
- switch (delta >> 9) {
- case -6: case -5: case -4: case -3: case -2:
- psd = next;
- break;
- case -1:
- psd = next + latab[(-delta) >> 1];
- break;
- case 0:
- psd += latab[delta >> 1];
- break;
- }
- }
- /* minpsd = -289 */
- UPDATE_LEAK ();
- mask = (fastleak < slowleak) ? fastleak : slowleak;
- COMPUTE_MASK ();
- i++;
- j = startband;
- do {
- /* max(mask+4*exp)=147=-(minpsd+fgain-deltba-snroffset)>>5+4*exp */
- /* min(mask+4*exp)=-156=-(sgain-deltba-snroffset)>>5 */
- bap[j] = (baptab+156)[mask + 4 * exp[j]];
- } while (++j < endband);
- } while (j < end);
-}
projects / goodguy / history.git / blobdiff