1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
|
/*
* Generate a header file for hardcoded ff_cos_* tables
*
* Copyright (c) 2009 Reimar Döffinger <Reimar.Doeffinger@gmx.de>
*
* This file is part of Libav.
*
* 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.
*
* 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 Libav; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include <stdio.h>
#include <string.h>
#include <math.h>
#ifndef M_PI
#define M_PI 3.14159265358979323846
#endif
#define BITS 16
#define FLOATFMT "%.18e"
#define FIXEDFMT "%6d"
static int clip_f15(int v)
{
return v < -32767 ? -32767 :
v > 32767 ? 32767 :
v;
}
static void printval(double val, int fixed)
{
if (fixed)
printf(" "FIXEDFMT",", clip_f15(lrint(val * (double)(1<<15))));
else
printf(" "FLOATFMT",", val);
}
int main(int argc, char *argv[])
{
int i, j;
int do_sin = argc > 1 && !strcmp(argv[1], "sin");
int fixed = argc > 1 && strstr(argv[1], "fixed");
double (*func)(double) = do_sin ? sin : cos;
printf("/* This file was automatically generated. */\n");
printf("#define CONFIG_FFT_FLOAT %d\n", !fixed);
printf("#include \"libavcodec/%s\"\n", do_sin ? "rdft.h" : "fft.h");
for (i = 4; i <= BITS; i++) {
int m = 1 << i;
double freq = 2*M_PI/m;
printf("%s(%i) = {\n ", do_sin ? "SINTABLE" : "COSTABLE", m);
for (j = 0; j < m/2 - 1; j++) {
int idx = j > m/4 ? m/2 - j : j;
if (do_sin && j >= m/4)
idx = m/4 - j;
printval(func(idx*freq), fixed);
if ((j & 3) == 3)
printf("\n ");
}
printval(func(do_sin ? -(m/4 - 1)*freq : freq), fixed);
printf("\n};\n");
}
return 0;
}
|
