| 1 | /* |
| 2 | * Generate a header file for hardcoded ff_cos_* tables |
| 3 | * |
| 4 | * Copyright (c) 2009 Reimar Döffinger <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 | |
| 31 | static int clip_f15(int v) |
| 32 | { |
| 33 | return v < -32767 ? -32767 : |
| 34 | v > 32767 ? 32767 : |
| 35 | v; |
| 36 | } |
| 37 | |
| 38 | static 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 | |
| 52 | int 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 | } |