| 1 | /* |
| 2 | * Header file for hardcoded AAC cube-root table |
| 3 | * |
| 4 | * Copyright (c) 2010 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 | #ifndef AVCODEC_CBRT_TABLEGEN_H |
| 24 | #define AVCODEC_CBRT_TABLEGEN_H |
| 25 | |
| 26 | #include <stdint.h> |
| 27 | #include <math.h> |
| 28 | #include "libavutil/attributes.h" |
| 29 | |
| 30 | #if CONFIG_HARDCODED_TABLES |
| 31 | #define cbrt_tableinit() |
| 32 | #include "libavcodec/cbrt_tables.h" |
| 33 | #else |
| 34 | static uint32_t cbrt_tab[1 << 13]; |
| 35 | |
| 36 | static av_cold void cbrt_tableinit(void) |
| 37 | { |
| 38 | if (!cbrt_tab[(1<<13) - 1]) { |
| 39 | int i; |
| 40 | /* cbrtf() isn't available on all systems, so we use powf(). */ |
| 41 | for (i = 0; i < 1<<13; i++) { |
| 42 | union { |
| 43 | float f; |
| 44 | uint32_t i; |
| 45 | } f; |
| 46 | f.f = pow(i, 1.0 / 3.0) * i; |
| 47 | cbrt_tab[i] = f.i; |
| 48 | } |
| 49 | } |
| 50 | } |
| 51 | #endif /* CONFIG_HARDCODED_TABLES */ |
| 52 | |
| 53 | #endif /* AVCODEC_CBRT_TABLEGEN_H */ |