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/*
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 * copyright (c) 2005 Michael Niedermayer <michaelni@gmx.at>
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 *
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 * This file is part of FFmpeg.
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 *
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 * FFmpeg is free software; you can redistribute it and/or
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 * modify it under the terms of the GNU Lesser General Public
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 * License as published by the Free Software Foundation; either
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 * version 2.1 of the License, or (at your option) any later version.
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 *
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 * FFmpeg is distributed in the hope that it will be useful,
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 * but WITHOUT ANY WARRANTY; without even the implied warranty of
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 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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 * Lesser General Public License for more details.
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 *
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 * You should have received a copy of the GNU Lesser General Public
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 * License along with FFmpeg; if not, write to the Free Software
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 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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 */
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#ifndef FFMPEG_MATHEMATICS_H
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#define FFMPEG_MATHEMATICS_H
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#include <stdint.h>
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#include <math.h>
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#include "rational.h"
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#ifndef M_E
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#define M_E            2.7182818284590452354   /* e */
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#endif
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#ifndef M_LN2
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#define M_LN2          0.69314718055994530942  /* log_e 2 */
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#endif
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#ifndef M_LN10
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#define M_LN10         2.30258509299404568402  /* log_e 10 */
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#endif
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#ifndef M_SQRT1_2
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#define M_SQRT1_2      0.70710678118654752440  /* 1/sqrt(2) */
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#endif
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enum AVRounding {
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    AV_ROUND_ZERO     = 0, ///< round toward zero
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    AV_ROUND_INF      = 1, ///< round away from zero
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    AV_ROUND_DOWN     = 2, ///< round toward -infinity
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    AV_ROUND_UP       = 3, ///< round toward +infinity
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    AV_ROUND_NEAR_INF = 5, ///< round to nearest and halfway cases away from zero
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};
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/**
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 * rescale a 64bit integer with rounding to nearest.
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 * a simple a*b/c isn't possible as it can overflow
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 */
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int64_t av_rescale(int64_t a, int64_t b, int64_t c) av_const;
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/**
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 * rescale a 64bit integer with specified rounding.
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 * a simple a*b/c isn't possible as it can overflow
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 */
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int64_t av_rescale_rnd(int64_t a, int64_t b, int64_t c, enum AVRounding) av_const;
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/**
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 * rescale a 64bit integer by 2 rational numbers.
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 */
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int64_t av_rescale_q(int64_t a, AVRational bq, AVRational cq) av_const;
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#endif /* FFMPEG_MATHEMATICS_H */