[deb_ffmpeg.git] / ffmpeg / libavcodec / cbrt_tablegen.h

/*
 * Header file for hardcoded AAC cube-root table
 *
 * Copyright (c) 2010 Reimar Döffinger <Reimar.Doeffinger@gmx.de>
 *
 * 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_CBRT_TABLEGEN_H
#define AVCODEC_CBRT_TABLEGEN_H

#include <stdint.h>
#include <math.h>
#include "libavutil/attributes.h"

#if CONFIG_HARDCODED_TABLES
#define cbrt_tableinit()
#include "libavcodec/cbrt_tables.h"
#else
static uint32_t cbrt_tab[1 << 13];

static av_cold void cbrt_tableinit(void)
{
    if (!cbrt_tab[(1<<13) - 1]) {
        int i;
        /* cbrtf() isn't available on all systems, so we use powf(). */
        for (i = 0; i < 1<<13; i++) {
            union {
                float f;
                uint32_t i;
            } f;
            f.f = pow(i, 1.0 / 3.0) * i;
            cbrt_tab[i] = f.i;
        }
    }
}
#endif /* CONFIG_HARDCODED_TABLES */

#endif /* AVCODEC_CBRT_TABLEGEN_H */
Commit	Line	Data
2ba45a60 DM	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 */