2 * Generate a header file for hardcoded ff_cos_* tables
4 * Copyright (c) 2009 Reimar Döffinger <Reimar.Doeffinger@gmx.de>
6 * This file is part of FFmpeg.
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.
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.
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
28 #define FLOATFMT "%.18e"
29 #define FIXEDFMT "%6d"
31 static int clip_f15(int v
)
33 return v
< -32767 ? -32767 :
38 static void printval(double val
, int fixed
)
41 /* lrint() isn't always available, so round and cast manually. */
42 double new_val
= val
* (double) (1 << 15);
44 new_val
= new_val
>= 0 ? floor(new_val
+ 0.5) : ceil(new_val
- 0.5);
46 printf(" "FIXEDFMT
",", clip_f15((long int) new_val
));
48 printf(" "FLOATFMT
",", val
);
52 int main(int argc
, char *argv
[])
55 int do_sin
= argc
> 1 && !strcmp(argv
[1], "sin");
56 int fixed
= argc
> 1 && strstr(argv
[1], "fixed");
57 double (*func
)(double) = do_sin
? sin
: cos
;
59 printf("/* This file was automatically generated. */\n");
60 printf("#define FFT_FLOAT %d\n", !fixed
);
61 printf("#include \"libavcodec/%s\"\n", do_sin
? "rdft.h" : "fft.h");
62 for (i
= 4; i
<= BITS
; i
++) {
64 double freq
= 2*3.14159265358979323846/m
;
65 printf("%s(%i) = {\n ", do_sin
? "SINTABLE" : "COSTABLE", m
);
66 for (j
= 0; j
< m
/2 - 1; j
++) {
67 int idx
= j
> m
/4 ? m
/2 - j
: j
;
68 if (do_sin
&& j
>= m
/4)
70 printval(func(idx
*freq
), fixed
);
74 printval(func(do_sin
? -(m
/4 - 1)*freq
: freq
), fixed
);