1/* 2 * Header file for hardcoded mpegaudiodec 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#ifndef MPEGAUDIO_TABLEGEN_H 24#define MPEGAUDIO_TABLEGEN_H 25 26#include <stdint.h> 27// do not use libavutil/mathematics.h since this is compiled both 28// for the host and the target and config.h is only valid for the target 29#include <math.h> 30 31#define TABLE_4_3_SIZE (8191 + 16)*4 32#if CONFIG_HARDCODED_TABLES 33#define mpegaudio_tableinit() 34#include "libavcodec/mpegaudio_tables.h" 35#else 36static int8_t table_4_3_exp[TABLE_4_3_SIZE]; 37static uint32_t table_4_3_value[TABLE_4_3_SIZE]; 38static uint32_t exp_table[512]; 39static uint32_t expval_table[512][16]; 40 41static void mpegaudio_tableinit(void) 42{ 43 int i, value, exponent; 44 for (i = 1; i < TABLE_4_3_SIZE; i++) { 45 double value = i / 4; 46 double f, fm; 47 int e, m; 48 f = value * cbrtf(value) * pow(2, (i & 3) * 0.25); 49 fm = frexp(f, &e); 50 m = (uint32_t)(fm * (1LL << 31) + 0.5); 51 e += FRAC_BITS - 31 + 5 - 100; 52 53 /* normalized to FRAC_BITS */ 54 table_4_3_value[i] = m; 55 table_4_3_exp[i] = -e; 56 } 57 for (exponent = 0; exponent < 512; exponent++) { 58 for (value = 0; value < 16; value++) { 59 double f = (double)value * cbrtf(value) * pow(2, (exponent - 400) * 0.25 + FRAC_BITS + 5); 60 expval_table[exponent][value] = llrint(f); 61 } 62 exp_table[exponent] = expval_table[exponent][1]; 63 } 64} 65#endif /* CONFIG_HARDCODED_TABLES */ 66 67#endif /* MPEGAUDIO_TABLEGEN_H */ 68