adding ffmpeg specific version

1 files changed, 72 insertions, 0 deletions

diff --git a/ffmpeg1/libavcodec/mpegaudio_tablegen.h b/ffmpeg1/libavcodec/mpegaudio_tablegen.h
new file mode 100644
index 0000000..6c15d3c
--- /dev/null
+++ b/ffmpeg1/libavcodec/mpegaudio_tablegen.h
@@ -0,0 +1,72 @@
+/*
+ * Header file for hardcoded mpegaudiodec tables
+ *
+ * Copyright (c) 2009 Reimar Döffinger <Reimar.Doeffinger@gmx.de>
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#ifndef AVCODEC_MPEGAUDIO_TABLEGEN_H
+#define AVCODEC_MPEGAUDIO_TABLEGEN_H
+
+#include <stdint.h>
+#include <math.h>
+
+#define TABLE_4_3_SIZE (8191 + 16)*4
+#if CONFIG_HARDCODED_TABLES
+#define mpegaudio_tableinit()
+#include "libavcodec/mpegaudio_tables.h"
+#else
+static int8_t   table_4_3_exp[TABLE_4_3_SIZE];
+static uint32_t table_4_3_value[TABLE_4_3_SIZE];
+static uint32_t exp_table_fixed[512];
+static uint32_t expval_table_fixed[512][16];
+static float exp_table_float[512];
+static float expval_table_float[512][16];
+
+#define FRAC_BITS 23
+#define IMDCT_SCALAR 1.759
+
+static void mpegaudio_tableinit(void)
+{
+    int i, value, exponent;
+    for (i = 1; i < TABLE_4_3_SIZE; i++) {
+        double value = i / 4;
+        double f, fm;
+        int e, m;
+        f  = value / IMDCT_SCALAR * cbrtf(value) * pow(2, (i & 3) * 0.25);
+        fm = frexp(f, &e);
+        m  = (uint32_t)(fm * (1LL << 31) + 0.5);
+        e += FRAC_BITS - 31 + 5 - 100;
+
+        /* normalized to FRAC_BITS */
+        table_4_3_value[i] =  m;
+        table_4_3_exp[i]   = -e;
+    }
+    for (exponent = 0; exponent < 512; exponent++) {
+        for (value = 0; value < 16; value++) {
+            double f = (double)value * cbrtf(value) * pow(2, (exponent - 400) * 0.25 + FRAC_BITS + 5) / IMDCT_SCALAR;
+            expval_table_fixed[exponent][value] = llrint(f);
+            expval_table_float[exponent][value] = f;
+        }
+        exp_table_fixed[exponent] = expval_table_fixed[exponent][1];
+        exp_table_float[exponent] = expval_table_float[exponent][1];
+    }
+}
+#endif /* CONFIG_HARDCODED_TABLES */
+
+#endif /* AVCODEC_MPEGAUDIO_TABLEGEN_H */