unit ffm.rational;

{$i ffmpeg.inc}

interface

/// *
// * rational numbers
// * Copyright (c) 2003 Michael Niedermayer <michaelni@gmx.at>
// *
// * This file is part of ffm.
// *
// * 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
// */
//
/// **
// * @file
// * rational numbers
// * @author Michael Niedermayer <michaelni@gmx.at>
// */
//
// #ifndef AVUTIL_RATIONAL_H
// #define AVUTIL_RATIONAL_H
//
// #include <stdint.h>
// #include <limits.h>
// #include "attributes.h"
//
/// **
// * @addtogroup lavu_math
// * @{
// */
type
  (*
    * rational number numerator/denominator
  *)
  pAVRational = ^TAVRational;

  TAVRational = {packed} record
    num: Integer;
    /// < numerator
    den: Integer;
    /// < denominator
  end;

  /// **
  // * Compare two rationals.
  // * @param a first rational
  // * @param b second rational
  // * @return 0 if a==b, 1 if a>b, -1 if a<b, and INT_MIN if one of the
  // * values is of the form 0/0
  // */
  // static inline int av_cmp_q(AVRational a, AVRational b){
  // const int64_t tmp= a.num * (int64_t)b.den - b.num * (int64_t)a.den;
  //
  // if(tmp) return (int)((tmp ^ a.den ^ b.den)>>63)|1;
  // else if(b.den && a.den) return 0;
  // else if(a.num && b.num) return (a.num>>31) - (b.num>>31);
  // else                    return INT_MIN;
  // }
  //
  /// **
  // * Convert rational to double.
  // * @param a rational to convert
  // * @return (double) a
  // */
  // static inline double av_q2d(AVRational a){
  // return a.num / (double) a.den;
  // }
  //
  /// **
  // * Reduce a fraction.
  // * This is useful for framerate calculations.
  // * @param dst_num destination numerator
  // * @param dst_den destination denominator
  // * @param num source numerator
  // * @param den source denominator
  // * @param max the maximum allowed for dst_num & dst_den
  // * @return 1 if exact, 0 otherwise
  // */
  // int av_reduce(int *dst_num, int *dst_den, int64_t num, int64_t den, int64_t max);
  //
  /// **
  // * Multiply two rationals.
  // * @param b first rational
  // * @param c second rational
  // * @return b*c
  // */
  // AVRational av_mul_q(AVRational b, AVRational c) av_const;
  //
  /// **
  // * Divide one rational by another.
  // * @param b first rational
  // * @param c second rational
  // * @return b/c
  // */
  // AVRational av_div_q(AVRational b, AVRational c) av_const;
  //
  /// **
  // * Add two rationals.
  // * @param b first rational
  // * @param c second rational
  // * @return b+c
  // */
  // AVRational av_add_q(AVRational b, AVRational c) av_const;
  //
  /// **
  // * Subtract one rational from another.
  // * @param b first rational
  // * @param c second rational
  // * @return b-c
  // */
  // AVRational av_sub_q(AVRational b, AVRational c) av_const;
  //
  /// **
  // * Invert a rational.
  // * @param q value
  // * @return 1 / q
  // */
  // static av_always_inline AVRational av_inv_q(AVRational q)
  // {
  // AVRational r = { q.den, q.num };
  // return r;
  // }
  //
  /// **
  // * Convert a double precision floating point number to a rational.
  // * inf is expressed as {1,0} or {-1,0} depending on the sign.
  // *
  // * @param d double to convert
  // * @param max the maximum allowed numerator and denominator
  // * @return (AVRational) d
  // */
  // AVRational av_d2q(double d, int max) av_const;
  //
  /// **
  // * @return 1 if q1 is nearer to q than q2, -1 if q2 is nearer
  // * than q1, 0 if they have the same distance.
  // */
  // int av_nearer_q(AVRational q, AVRational q1, AVRational q2);
  //
  /// **
  // * Find the nearest value in q_list to q.
  // * @param q_list an array of rationals terminated by {0, 0}
  // * @return the index of the nearest value found in the array
  // */
  // int av_find_nearest_q_idx(AVRational q, const AVRational* q_list);
  //
  /// **
  // * @}
  // */

implementation

end.