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+(*
+ * rational numbers
+ * Copyright (c) 2003 Michael Niedermayer <michaelni@gmx.at>
+ *
+ * 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 of the License, or (at your option) any later version.
+ *
+ * This library 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * This is a part of Pascal porting of ffmpeg.
+ * - Originally by Victor Zinetz for Delphi and Free Pascal on Windows.
+ * - For Mac OS X, some modifications were made by The Creative CAT, denoted as CAT
+ * in the source codes.
+ * - Changes and updates by the UltraStar Deluxe Team
+ *
+ * Conversion of libavutil/rational.h
+ * avutil version 50.43.0
+ *
+ *)
+
+unit rational;
+
+{$IFDEF FPC}
+ {$MODE DELPHI}
+ {$PACKENUM 4} (* use 4-byte enums *)
+ {$PACKRECORDS C} (* C/C++-compatible record packing *)
+{$ELSE}
+ {$MINENUMSIZE 4} (* use 4-byte enums *)
+{$ENDIF}
+
+{$I switches.inc}
+
+interface
+
+uses
+ ctypes,
+ UConfig;
+
+type
+ (*
+ * rational number numerator/denominator
+ *)
+ PAVRational = ^TAVRational;
+ TAVRational = record
+ num: cint; ///< numerator
+ den: cint; ///< denominator
+ end;
+
+ TAVRationalArray = array[0 .. (MaxInt div SizeOf(TAVRational))-1] of TAVRational;
+ PAVRationalArray = ^TAVRationalArray;
+
+(**
+ * Compare two rationals.
+ * @param a first rational
+ * @param b second rational
+ * @return 0 if a==b, 1 if a>b and -1 if a<b
+ *)
+function av_cmp_q(a: TAVRational; b: TAVRational): cint; {$IFDEF HasInline}inline;{$ENDIF}
+
+(**
+ * Convert rational to double.
+ * @param a rational to convert
+ * @return (double) a
+ *)
+function av_q2d(a: TAVRational): cdouble; {$IFDEF HasInline}inline;{$ENDIF}
+
+(**
+ * 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
+ *)
+function av_reduce(dst_num: PCint; dst_den: PCint; num: cint64; den: cint64; max: cint64): cint;
+ cdecl; external av__util;
+
+(**
+ * Multiply two rationals.
+ * @param b first rational
+ * @param c second rational
+ * @return b*c
+ *)
+function av_mul_q(b: TAVRational; c: TAVRational): TAVRational;
+ cdecl; external av__util; {av_const}
+
+(**
+ * Divide one rational by another.
+ * @param b first rational
+ * @param c second rational
+ * @return b/c
+ *)
+function av_div_q(b: TAVRational; c: TAVRational): TAVRational;
+ cdecl; external av__util; {av_const}
+
+(**
+ * Add two rationals.
+ * @param b first rational
+ * @param c second rational
+ * @return b+c
+ *)
+function av_add_q(b: TAVRational; c: TAVRational): TAVRational;
+ cdecl; external av__util; {av_const}
+
+(**
+ * Subtract one rational from another.
+ * @param b first rational
+ * @param c second rational
+ * @return b-c
+ *)
+function av_sub_q(b: TAVRational; c: TAVRational): TAVRational;
+ cdecl; external av__util; {av_const}
+
+(**
+ * 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
+ *)
+function av_d2q(d: cdouble; max: cint): TAVRational;
+ cdecl; external av__util; {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.
+ *)
+function av_nearer_q(q, q1, q2: TAVRational): cint;
+ cdecl; external av__util;
+
+(**
+ * 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
+ *)
+function av_find_nearest_q_idx(q: TAVRational; q_list: {const} PAVRationalArray): cint;
+ cdecl; external av__util;
+
+implementation
+
+function av_cmp_q (a: TAVRational; b: TAVRational): cint;
+var
+ tmp: cint64;
+begin
+ tmp := a.num * cint64(b.den) - b.num * cint64(a.den);
+
+ if (tmp <> 0) then
+ Result := (tmp shr 63) or 1
+ else
+ Result := 0
+end;
+
+function av_q2d(a: TAVRational): cdouble;
+begin
+ Result := a.num / a.den;
+end;
+
+end.