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cbrt_tablegen.h
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1 /*
2  * Header file for hardcoded AAC cube-root table
3  *
4  * Copyright (c) 2010 Reimar Döffinger <Reimar.Doeffinger@gmx.de>
5  *
6  * This file is part of FFmpeg.
7  *
8  * FFmpeg is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU Lesser General Public
10  * License as published by the Free Software Foundation; either
11  * version 2.1 of the License, or (at your option) any later version.
12  *
13  * FFmpeg is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16  * Lesser General Public License for more details.
17  *
18  * You should have received a copy of the GNU Lesser General Public
19  * License along with FFmpeg; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22 
23 #ifndef AVCODEC_CBRT_TABLEGEN_H
24 #define AVCODEC_CBRT_TABLEGEN_H
25 
26 #include <stdint.h>
27 #include <math.h>
28 #include "libavutil/attributes.h"
29 #include "libavutil/intfloat.h"
30 #include "libavcodec/aac_defines.h"
31 
32 #if USE_FIXED
33 #define CBRT(x) lrint((x) * 8192)
34 #else
35 #define CBRT(x) av_float2int((float)(x))
36 #endif
37 
38 #if CONFIG_HARDCODED_TABLES
39 #if USE_FIXED
40 #define cbrt_tableinit_fixed()
41 #include "libavcodec/cbrt_fixed_tables.h"
42 #else
43 #define cbrt_tableinit()
44 #include "libavcodec/cbrt_tables.h"
45 #endif
46 #else
47 static uint32_t cbrt_tab[1 << 13];
48 
50 {
51  static double cbrt_tab_dbl[1 << 13];
52  if (!cbrt_tab[(1<<13) - 1]) {
53  int i, j, k;
54  double cbrt_val;
55 
56  for (i = 1; i < 1<<13; i++)
57  cbrt_tab_dbl[i] = 1;
58 
59  /* have to take care of non-squarefree numbers */
60  for (i = 2; i < 90; i++) {
61  if (cbrt_tab_dbl[i] == 1) {
62  cbrt_val = i * cbrt(i);
63  for (k = i; k < 1<<13; k *= i)
64  for (j = k; j < 1<<13; j += k)
65  cbrt_tab_dbl[j] *= cbrt_val;
66  }
67  }
68 
69  for (i = 91; i <= 8191; i+= 2) {
70  if (cbrt_tab_dbl[i] == 1) {
71  cbrt_val = i * cbrt(i);
72  for (j = i; j < 1<<13; j += i)
73  cbrt_tab_dbl[j] *= cbrt_val;
74  }
75  }
76 
77  for (i = 0; i < 1<<13; i++)
78  cbrt_tab[i] = CBRT(cbrt_tab_dbl[i]);
79  }
80 }
81 #endif /* CONFIG_HARDCODED_TABLES */
82 
83 #endif /* AVCODEC_CBRT_TABLEGEN_H */
Macro definitions for various function/variable attributes.
#define av_cold
Definition: attributes.h:82
#define cbrt
Definition: tablegen.h:35
#define AAC_RENAME(x)
Definition: aac_defines.h:83
typedef void(APIENTRY *FF_PFNGLACTIVETEXTUREPROC)(GLenum texture)
static uint32_t cbrt_tab[1<< 13]
Definition: cbrt_tablegen.h:47
static av_cold void AAC_RENAME() cbrt_tableinit(void)
Definition: cbrt_tablegen.h:49
#define CBRT(x)
Definition: cbrt_tablegen.h:35