/* * 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> #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) { /* lrint() isn't always available, so round and cast manually. */ double new_val = val * (double) (1 << 15); new_val = new_val >= 0 ? floor(new_val + 0.5) : ceil(new_val - 0.5); printf(" "FIXEDFMT",", clip_f15((long int) new_val)); } 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 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; }