Rename h264_idct_sse2.asm to h264_idct.asm; move inline IDCT asm from

[ffmpeg] / libavutil / rational.h

diff --git a/libavutil/rational.h b/libavutil/rational.h
index e4bfe5f7a62bae1c1fca58135bf234cc120e4cea..2dd0c2c5948e5480877bb13ca6421e7a31428794 100644 (file)
--- a/libavutil/rational.h
+++ b/libavutil/rational.h
@@ -1,34 +1,38 @@
 /*
- * Rational numbers
+ * rational numbers
  * Copyright (c) 2003 Michael Niedermayer <michaelni@gmx.at>
  *
- * This library is free software; you can redistribute it and/or
+ * 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 of the License, or (at your option) any later version.
+ * version 2.1 of the License, or (at your option) any later version.
  *
- * This library is distributed in the hope that it will be useful,
+ * 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 this library; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
- *
+ * 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.h
- * Rational numbers.
+ * @file
+ * rational numbers
  * @author Michael Niedermayer <michaelni@gmx.at>
  */
 
-#ifndef RATIONAL_H
-#define RATIONAL_H
+#ifndef AVUTIL_RATIONAL_H
+#define AVUTIL_RATIONAL_H
+
+#include <stdint.h>
+#include "attributes.h"
 
 /**
- * Rational number num/den.
+ * rational number numerator/denominator
  */
 typedef struct AVRational{
     int num; ///< numerator
@@ -36,7 +40,10 @@ typedef struct AVRational{
 } AVRational;
 
 /**
- * returns 0 if a==b, 1 if a>b and -1 if a<b.
+ * 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
  */
 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;
@@ -46,24 +53,77 @@ static inline int av_cmp_q(AVRational a, AVRational b){
 }
 
 /**
- * converts the given AVRational to a double.
+ * 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 usefull for framerate calculations
- * @param max the maximum allowed for dst_nom & dst_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_nom, int *dst_den, int64_t nom, int64_t den, int64_t max);
+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;
+
+/**
+ * Convert a double precision floating point number to a rational.
+ * @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);
 
-AVRational av_mul_q(AVRational b, AVRational c);
-AVRational av_div_q(AVRational b, AVRational c);
-AVRational av_add_q(AVRational b, AVRational c);
-AVRational av_sub_q(AVRational b, AVRational c);
-AVRational av_d2q(double d, int max);
+/**
+ * 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);
 
-#endif // RATIONAL_H
+#endif /* AVUTIL_RATIONAL_H */