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#define BITS 16 28#define FLOATFMT "%.18e" 29#define FIXEDFMT "%6d" 30 31static int clip_f15(int v) 32{ 33 return v < -32767 ? -32767 : 34 v > 32767 ? 32767 : 35 v; 36} 37 38static void printval(double val, int fixed) 39{ 40 if (fixed) { 41 /* lrint() isn't always available, so round and cast manually. */ 42 double new_val = val * (double) (1 << 15); 43 44 new_val = new_val >= 0 ? floor(new_val + 0.5) : ceil(new_val - 0.5); 45 46 printf(" "FIXEDFMT",", clip_f15((long int) new_val)); 47 } else { 48 printf(" "FLOATFMT",", val); 49 } 50} 51 52int main(int argc, char *argv[]) 53{ 54 int i, j; 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; 58 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++) { 63 int m = 1 << 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) 69 idx = m/4 - j; 70 printval(func(idx*freq), fixed); 71 if ((j & 3) == 3) 72 printf("\n "); 73 } 74 printval(func(do_sin ? -(m/4 - 1)*freq : freq), fixed); 75 printf("\n};\n"); 76 } 77 return 0; 78} 79