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-rw-r--r--liba52/bit_allocate.c260
1 files changed, 260 insertions, 0 deletions
diff --git a/liba52/bit_allocate.c b/liba52/bit_allocate.c
new file mode 100644
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--- /dev/null
+++ b/liba52/bit_allocate.c
@@ -0,0 +1,260 @@
+/*
+ * bit_allocate.c
+ * Copyright (C) 2000-2001 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 bit_allocate (a52_state_t * state, a52_ba_t * ba, int bndstart,
+ int start, int end, int fastleak, int slowleak,
+ uint8_t * exp, int8_t * bap)
+{
+ 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;
+ 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->fdcycod) >> halfrate;
+ fgain = 128 + 128 * ba->fgaincod;
+ sdecay = (15 + 2 * state->sdcycod) >> halfrate;
+ sgain = slowgain[state->sgaincod];
+ dbknee = dbpbtab[state->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->floorcod];
+ snroffset = 960 - 64 * state->csnroffst - 4 * ba->fsnroffst + floor;
+ floor >>= 5;
+
+ 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);
+}
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