X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=libavcodec%2Fmpegaudio_tablegen.h;h=8a3e51ae60a385dba148cdcbb4eea792fcddad39;hb=9ba3fc3e3d12c9ef00dcb0222b7ea0ccb5c4a091;hp=362c30b4beb15a774adb583ce42ec84283b0b5fe;hpb=52a4a077788a02a97cdfb8ce2f3a3107615c4d7b;p=ffmpeg

diff --git a/libavcodec/mpegaudio_tablegen.h b/libavcodec/mpegaudio_tablegen.h
index 362c30b4beb..8a3e51ae60a 100644
--- a/libavcodec/mpegaudio_tablegen.h
+++ b/libavcodec/mpegaudio_tablegen.h
@@ -3,29 +3,27 @@
  *
  * Copyright (c) 2009 Reimar Döffinger <Reimar.Doeffinger@gmx.de>
  *
- * This file is part of FFmpeg.
+ * This file is part of Libav.
  *
- * FFmpeg is free software; you can redistribute it and/or
+ * Libav 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,
+ * Libav 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
+ * License along with Libav; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
-#ifndef MPEGAUDIO_TABLEGEN_H
-#define MPEGAUDIO_TABLEGEN_H
+#ifndef AVCODEC_MPEGAUDIO_TABLEGEN_H
+#define AVCODEC_MPEGAUDIO_TABLEGEN_H
 
 #include <stdint.h>
-// do not use libavutil/mathematics.h since this is compiled both
-// for the host and the target and config.h is only valid for the target
 #include <math.h>
 
 #define TABLE_4_3_SIZE (8191 + 16)*4
@@ -33,36 +31,44 @@
 #define mpegaudio_tableinit()
 #include "libavcodec/mpegaudio_tables.h"
 #else
-static int8_t  table_4_3_exp[TABLE_4_3_SIZE];
+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[512];
-static uint32_t expval_table[512][16];
+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
 
 static void mpegaudio_tableinit(void)
 {
-    int i;
-    for(i=1;i<TABLE_4_3_SIZE;i++) {
-        double value = i/4;
+    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 * cbrtf(value) * pow(2, (i&3)*0.25);
+        /* cbrtf() isn't available on all systems, so we use powf(). */
+        f  = value * powf(value, 1.0 / 3.0) * pow(2, (i & 3) * 0.25);
         fm = frexp(f, &e);
-        m = (uint32_t)(fm*(1LL<<31) + 0.5);
-        e+= FRAC_BITS - 31 + 5 - 100;
+        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;
+        table_4_3_value[i] =  m;
+        table_4_3_exp[i]   = -e;
     }
-    for(i=0; i<512*16; i++){
-        double value = i & 15;
-        int exponent= (i>>4);
-        double f= value * cbrtf(value) * pow(2, (exponent-400)*0.25 + FRAC_BITS + 5);
-        expval_table[exponent][i&15]= llrint(f);
-        if((i&15)==1)
-            exp_table[exponent]= llrint(f);
+    for (exponent = 0; exponent < 512; exponent++) {
+        for (value = 0; value < 16; value++) {
+            /* cbrtf() isn't available on all systems, so we use powf(). */
+            double f = (double)value * powf(value, 1.0 / 3.0) * pow(2, (exponent - 400) * 0.25 + FRAC_BITS + 5);
+            /* llrint() isn't always available, so round and cast manually. */
+            expval_table_fixed[exponent][value] = (long long int) (f >= 0 ? floor(f + 0.5) : ceil(f - 0.5));
+            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 /* MPEGAUDIO_TABLEGEN_H */
+#endif /* AVCODEC_MPEGAUDIO_TABLEGEN_H */