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5086720993
You cannot count on it being present on all systems, and you cannot include libm.h in a host tool, so just hard code a baseline implementation. Signed-off-by: Derek Buitenhuis <derek.buitenhuis@gmail.com>
79 lines
2.4 KiB
C
79 lines
2.4 KiB
C
/*
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* Generate a header file for hardcoded ff_cos_* tables
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*
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* Copyright (c) 2009 Reimar Döffinger <Reimar.Doeffinger@gmx.de>
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*
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* This file is part of FFmpeg.
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*
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* FFmpeg is free software; you can redistribute it and/or
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* modify it under the terms of the GNU Lesser General Public
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* License as published by the Free Software Foundation; either
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* version 2.1 of the License, or (at your option) any later version.
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*
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* FFmpeg is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* Lesser General Public License for more details.
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*
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* You should have received a copy of the GNU Lesser General Public
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* License along with FFmpeg; if not, write to the Free Software
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* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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*/
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#include <stdio.h>
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#include <string.h>
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#include <math.h>
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#define BITS 16
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#define FLOATFMT "%.18e"
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#define FIXEDFMT "%6d"
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static int clip_f15(int v)
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{
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return v < -32767 ? -32767 :
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v > 32767 ? 32767 :
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v;
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}
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static void printval(double val, int fixed)
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{
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if (fixed) {
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/* lrint() isn't always available, so round and cast manually. */
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double new_val = val * (double) (1 << 15);
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new_val = new_val >= 0 ? floor(new_val + 0.5) : ceil(new_val - 0.5);
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printf(" "FIXEDFMT",", clip_f15((long int) new_val));
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} else {
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printf(" "FLOATFMT",", val);
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}
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}
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int main(int argc, char *argv[])
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{
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int i, j;
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int do_sin = argc > 1 && !strcmp(argv[1], "sin");
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int fixed = argc > 1 && strstr(argv[1], "fixed");
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double (*func)(double) = do_sin ? sin : cos;
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printf("/* This file was automatically generated. */\n");
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printf("#define CONFIG_FFT_FLOAT %d\n", !fixed);
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printf("#include \"libavcodec/%s\"\n", do_sin ? "rdft.h" : "fft.h");
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for (i = 4; i <= BITS; i++) {
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int m = 1 << i;
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double freq = 2*3.14159265358979323846/m;
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printf("%s(%i) = {\n ", do_sin ? "SINTABLE" : "COSTABLE", m);
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for (j = 0; j < m/2 - 1; j++) {
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int idx = j > m/4 ? m/2 - j : j;
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if (do_sin && j >= m/4)
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idx = m/4 - j;
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printval(func(idx*freq), fixed);
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if ((j & 3) == 3)
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printf("\n ");
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}
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printval(func(do_sin ? -(m/4 - 1)*freq : freq), fixed);
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printf("\n};\n");
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}
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return 0;
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}
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