diff options
Diffstat (limited to 'faad2/src/libfaad/drc.c')
| -rw-r--r-- | faad2/src/libfaad/drc.c | 173 |
1 files changed, 173 insertions, 0 deletions
diff --git a/faad2/src/libfaad/drc.c b/faad2/src/libfaad/drc.c new file mode 100644 index 0000000..7a99d4a --- /dev/null +++ b/faad2/src/libfaad/drc.c @@ -0,0 +1,173 @@ +/*
+** FAAD2 - Freeware Advanced Audio (AAC) Decoder including SBR decoding
+** Copyright (C) 2003-2005 M. Bakker, Nero AG, http://www.nero.com
+**
+** This program 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.
+**
+** This program 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.
+**
+** Any non-GPL usage of this software or parts of this software is strictly
+** forbidden.
+**
+** The "appropriate copyright message" mentioned in section 2c of the GPLv2
+** must read: "Code from FAAD2 is copyright (c) Nero AG, www.nero.com"
+**
+** Commercial non-GPL licensing of this software is possible.
+** For more info contact Nero AG through Mpeg4AAClicense@nero.com.
+**
+** $Id: drc.c,v 1.28 2007/11/01 12:33:30 menno Exp $
+**/
+
+#include "common.h"
+#include "structs.h"
+
+#include <stdlib.h>
+#include <string.h>
+#include "syntax.h"
+#include "drc.h"
+
+drc_info *drc_init(real_t cut, real_t boost)
+{
+ drc_info *drc = (drc_info*)faad_malloc(sizeof(drc_info));
+ memset(drc, 0, sizeof(drc_info));
+
+ drc->ctrl1 = cut;
+ drc->ctrl2 = boost;
+
+ drc->num_bands = 1;
+ drc->band_top[0] = 1024/4 - 1;
+ drc->dyn_rng_sgn[0] = 1;
+ drc->dyn_rng_ctl[0] = 0;
+
+ return drc;
+}
+
+void drc_end(drc_info *drc)
+{
+ if (drc) faad_free(drc);
+}
+
+#ifdef FIXED_POINT
+static real_t drc_pow2_table[] =
+{
+ COEF_CONST(0.5146511183),
+ COEF_CONST(0.5297315472),
+ COEF_CONST(0.5452538663),
+ COEF_CONST(0.5612310242),
+ COEF_CONST(0.5776763484),
+ COEF_CONST(0.5946035575),
+ COEF_CONST(0.6120267717),
+ COEF_CONST(0.6299605249),
+ COEF_CONST(0.6484197773),
+ COEF_CONST(0.6674199271),
+ COEF_CONST(0.6869768237),
+ COEF_CONST(0.7071067812),
+ COEF_CONST(0.7278265914),
+ COEF_CONST(0.7491535384),
+ COEF_CONST(0.7711054127),
+ COEF_CONST(0.7937005260),
+ COEF_CONST(0.8169577266),
+ COEF_CONST(0.8408964153),
+ COEF_CONST(0.8655365610),
+ COEF_CONST(0.8908987181),
+ COEF_CONST(0.9170040432),
+ COEF_CONST(0.9438743127),
+ COEF_CONST(0.9715319412),
+ COEF_CONST(1.0000000000),
+ COEF_CONST(1.0293022366),
+ COEF_CONST(1.0594630944),
+ COEF_CONST(1.0905077327),
+ COEF_CONST(1.1224620483),
+ COEF_CONST(1.1553526969),
+ COEF_CONST(1.1892071150),
+ COEF_CONST(1.2240535433),
+ COEF_CONST(1.2599210499),
+ COEF_CONST(1.2968395547),
+ COEF_CONST(1.3348398542),
+ COEF_CONST(1.3739536475),
+ COEF_CONST(1.4142135624),
+ COEF_CONST(1.4556531828),
+ COEF_CONST(1.4983070769),
+ COEF_CONST(1.5422108254),
+ COEF_CONST(1.5874010520),
+ COEF_CONST(1.6339154532),
+ COEF_CONST(1.6817928305),
+ COEF_CONST(1.7310731220),
+ COEF_CONST(1.7817974363),
+ COEF_CONST(1.8340080864),
+ COEF_CONST(1.8877486254),
+ COEF_CONST(1.9430638823)
+};
+#endif
+
+void drc_decode(drc_info *drc, real_t *spec)
+{
+ uint16_t i, bd, top;
+#ifdef FIXED_POINT
+ int32_t exp, frac;
+#else
+ real_t factor, exp;
+#endif
+ uint16_t bottom = 0;
+
+ if (drc->num_bands == 1)
+ drc->band_top[0] = 1024/4 - 1;
+
+ for (bd = 0; bd < drc->num_bands; bd++)
+ {
+ top = 4 * (drc->band_top[bd] + 1);
+
+#ifndef FIXED_POINT
+ /* Decode DRC gain factor */
+ if (drc->dyn_rng_sgn[bd]) /* compress */
+ exp = -drc->ctrl1 * (drc->dyn_rng_ctl[bd] - (DRC_REF_LEVEL - drc->prog_ref_level))/REAL_CONST(24.0);
+ else /* boost */
+ exp = drc->ctrl2 * (drc->dyn_rng_ctl[bd] - (DRC_REF_LEVEL - drc->prog_ref_level))/REAL_CONST(24.0);
+ factor = (real_t)pow(2.0, exp);
+
+ /* Apply gain factor */
+ for (i = bottom; i < top; i++)
+ spec[i] *= factor;
+#else
+ /* Decode DRC gain factor */
+ if (drc->dyn_rng_sgn[bd]) /* compress */
+ {
+ exp = -1 * (drc->dyn_rng_ctl[bd] - (DRC_REF_LEVEL - drc->prog_ref_level))/ 24;
+ frac = -1 * (drc->dyn_rng_ctl[bd] - (DRC_REF_LEVEL - drc->prog_ref_level)) % 24;
+ } else { /* boost */
+ exp = (drc->dyn_rng_ctl[bd] - (DRC_REF_LEVEL - drc->prog_ref_level))/ 24;
+ frac = (drc->dyn_rng_ctl[bd] - (DRC_REF_LEVEL - drc->prog_ref_level)) % 24;
+ }
+
+ /* Apply gain factor */
+ if (exp < 0)
+ {
+ for (i = bottom; i < top; i++)
+ {
+ spec[i] >>= -exp;
+ if (frac)
+ spec[i] = MUL_R(spec[i],drc_pow2_table[frac+23]);
+ }
+ } else {
+ for (i = bottom; i < top; i++)
+ {
+ spec[i] <<= exp;
+ if (frac)
+ spec[i] = MUL_R(spec[i],drc_pow2_table[frac+23]);
+ }
+ }
+#endif
+
+ bottom = top;
+ }
+}
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