merge FAAD2 - the GPL AAC decoder library.

xine_decoder.c is working, but demux_qt must send some needed
initialization data. currently it's hardcoded to play my test stream, so
it's not usable yet.

CVS patchset: 2267
CVS date: 2002/07/14 23:43:01

1 files changed, 77 insertions, 0 deletions

diff --git a/src/libfaad/drc.c b/src/libfaad/drc.c
new file mode 100644
index 000000000..0da3ed110
--- /dev/null
+++ b/src/libfaad/drc.c
@@ -0,0 +1,77 @@
+/*
+** FAAD - Freeware Advanced Audio Decoder
+** Copyright (C) 2002 M. Bakker
+**  
+** 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.
+**
+** $Id: drc.c,v 1.1 2002/07/14 23:43:01 miguelfreitas Exp $
+**/
+
+#include "common.h"
+
+#include <memory.h>
+#include "syntax.h"
+#include "drc.h"
+
+void init_drc(drc_info *drc, real_t cut, real_t boost)
+{
+    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;
+}
+
+void drc_decode(drc_info *drc, real_t *spec)
+{
+    uint16_t i, bd, top;
+    real_t factor;
+    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);
+
+        /* Decode DRC gain factor */
+        if (drc->dyn_rng_sgn[bd])  /* compress */
+            factor = (real_t)exp(LN2 * (-drc->ctrl1 * drc->dyn_rng_ctl[bd]/24.0));
+        else /* boost */
+            factor = (real_t)exp(LN2 * (drc->ctrl2 * drc->dyn_rng_ctl[bd]/24.0));
+
+        /* Level alignment between different programs (if desired) */
+        /* If program reference normalization is done in the digital domain,
+           modify factor to perform normalization.
+           prog_ref_level can alternatively be passed to the system for
+           modification of the level in the analog domain. Analog level
+           modification avoids problems with reduced DAC SNR (if signal is
+           attenuated) or clipping (if signal is boosted)
+         */
+        factor = MUL(factor,
+            (real_t)exp(LN05 * ((DRC_REF_LEVEL - drc->prog_ref_level)/24.0)));
+
+        /* Apply gain factor */
+        for (i = bottom; i < top; i++)
+            spec[i] = MUL(spec[i], factor);
+
+        bottom = top;
+    }
+}