/*
    dvb-math provides some complex fixed-point math
    operations shared between the dvb related stuff

    Copyright (C) 2006 Christoph Pfister (christophpfister@gmail.com)

    This library 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.

    This program 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 this library; if not, write to the Free Software
    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/

#ifndef DVB_MATH_H
#define DVB_MATH_H

/**
 * computes log2 of a value; the result is shifted left by 16 bits
 *
 * to use rational values you can use the following method:
 *   intlog2(value) = intlog2(value * 2^x) - x * 2^16
 *
 * example: intlog2(8) will give 3 << 16 = 3 * 2^16 = 196608
 * example: intlog2(9) will give 3 << 16 + ... = 207744 (rounded)
 * example: intlog2(1.5) = intlog2(3) - 2^16 = 38336 (rounded)
 *
 * @param value The value [ 0 gives a wrong result ]
 * @return log2(value) * 2^16
 */
extern unsigned int intlog2(unsigned int value);

/**
 * computes log10 of a value; the result is shifted left by 28 bits
 *
 * to use rational values you can use the following method:
 *   intlog10(value) = intlog10(value * 10^x) - x * 2^28
 *
 * example: intlog10(1000) will give 3 << 28 = 3 * 2^28
 *   due to the implementation intlog10(1000) might be not exactly 3 * 2^28
 *
 * look at intlog2 for similar examples
 *
 * @param value The value [ 0 gives a wrong result ]
 * @return log10(value) * 2^28
 */
extern unsigned int intlog10(unsigned int value);

#endif