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