From 150c9823e71a161e97003849cf8b2f55b21520bd Mon Sep 17 00:00:00 2001 From: Tim Redfern Date: Mon, 26 Aug 2013 15:10:18 +0100 Subject: adding ffmpeg specific version --- ffmpeg1/libavcodec/mpegaudio_tablegen.h | 72 +++++++++++++++++++++++++++++++++ 1 file changed, 72 insertions(+) create mode 100644 ffmpeg1/libavcodec/mpegaudio_tablegen.h (limited to 'ffmpeg1/libavcodec/mpegaudio_tablegen.h') diff --git a/ffmpeg1/libavcodec/mpegaudio_tablegen.h b/ffmpeg1/libavcodec/mpegaudio_tablegen.h new file mode 100644 index 0000000..6c15d3c --- /dev/null +++ b/ffmpeg1/libavcodec/mpegaudio_tablegen.h @@ -0,0 +1,72 @@ +/* + * Header file for hardcoded mpegaudiodec tables + * + * Copyright (c) 2009 Reimar Döffinger + * + * This file is part of FFmpeg. + * + * FFmpeg 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. + * + * FFmpeg 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 FFmpeg; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + */ + +#ifndef AVCODEC_MPEGAUDIO_TABLEGEN_H +#define AVCODEC_MPEGAUDIO_TABLEGEN_H + +#include +#include + +#define TABLE_4_3_SIZE (8191 + 16)*4 +#if CONFIG_HARDCODED_TABLES +#define mpegaudio_tableinit() +#include "libavcodec/mpegaudio_tables.h" +#else +static int8_t table_4_3_exp[TABLE_4_3_SIZE]; +static uint32_t table_4_3_value[TABLE_4_3_SIZE]; +static uint32_t exp_table_fixed[512]; +static uint32_t expval_table_fixed[512][16]; +static float exp_table_float[512]; +static float expval_table_float[512][16]; + +#define FRAC_BITS 23 +#define IMDCT_SCALAR 1.759 + +static void mpegaudio_tableinit(void) +{ + int i, value, exponent; + for (i = 1; i < TABLE_4_3_SIZE; i++) { + double value = i / 4; + double f, fm; + int e, m; + f = value / IMDCT_SCALAR * cbrtf(value) * pow(2, (i & 3) * 0.25); + fm = frexp(f, &e); + m = (uint32_t)(fm * (1LL << 31) + 0.5); + e += FRAC_BITS - 31 + 5 - 100; + + /* normalized to FRAC_BITS */ + table_4_3_value[i] = m; + table_4_3_exp[i] = -e; + } + for (exponent = 0; exponent < 512; exponent++) { + for (value = 0; value < 16; value++) { + double f = (double)value * cbrtf(value) * pow(2, (exponent - 400) * 0.25 + FRAC_BITS + 5) / IMDCT_SCALAR; + expval_table_fixed[exponent][value] = llrint(f); + expval_table_float[exponent][value] = f; + } + exp_table_fixed[exponent] = expval_table_fixed[exponent][1]; + exp_table_float[exponent] = expval_table_float[exponent][1]; + } +} +#endif /* CONFIG_HARDCODED_TABLES */ + +#endif /* AVCODEC_MPEGAUDIO_TABLEGEN_H */ -- cgit v1.2.3