1/*
2 * Generate a header file for hardcoded ff_cos_* tables
3 *
4 * Copyright (c) 2009 Reimar D��ffinger <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#include <stdio.h>
24#include <string.h>
25#include <math.h>
26
27#ifndef M_PI
28#define M_PI 3.14159265358979323846
29#endif
30#define BITS 16
31#define FLOATFMT "%.18e"
32
33int main(int argc, char *argv[])
34{
35    int i, j;
36    int do_sin = argc == 2 && !strcmp(argv[1], "sin");
37    double (*func)(double) = do_sin ? sin : cos;
38
39    printf("/* This file was generated by libavcodec/costablegen */\n");
40    printf("#include \"libavcodec/fft.h\"\n");
41    for (i = 4; i <= BITS; i++) {
42        int m = 1 << i;
43        double freq = 2*M_PI/m;
44        printf("%s(%i) = {\n   ", do_sin ? "SINTABLE" : "COSTABLE", m);
45        for (j = 0; j < m/2 - 1; j++) {
46            int idx = j > m/4 ? m/2 - j : j;
47            if (do_sin && j >= m/4)
48                idx = m/4 - j;
49            printf(" "FLOATFMT",", func(idx*freq));
50            if ((j & 3) == 3)
51                printf("\n   ");
52        }
53        printf(" "FLOATFMT"\n};\n", func(do_sin ? -(m/4 - 1)*freq : freq));
54    }
55    return 0;
56}
57