tests/examples: Mark some variables only used within their files as static.

[ffmpeg] / libavutil / mathematics.h

diff --git a/libavutil/mathematics.h b/libavutil/mathematics.h
index cb3591051a71d534ed386912aecdac84dab4021f..0b072ebe63cfcda52b757737651ba4a1e0fab453 100644 (file)
--- a/libavutil/mathematics.h
+++ b/libavutil/mathematics.h
@@ -1,20 +1,20 @@
 /*
  * copyright (c) 2005 Michael Niedermayer <michaelni@gmx.at>
  *
- * This file is part of FFmpeg.
+ * This file is part of Libav.
  *
- * FFmpeg is free software; you can redistribute it and/or
+ * Libav 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,
+ * Libav 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
+ * License along with Libav; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
@@ -23,7 +23,7 @@
 
 #include <stdint.h>
 #include <math.h>
-#include "common.h"
+#include "attributes.h"
 #include "rational.h"
 
 #ifndef M_E
@@ -35,12 +35,21 @@
 #ifndef M_LN10
 #define M_LN10         2.30258509299404568402  /* log_e 10 */
 #endif
+#ifndef M_LOG2_10
+#define M_LOG2_10      3.32192809488736234787  /* log_2 10 */
+#endif
+#ifndef M_PHI
+#define M_PHI          1.61803398874989484820   /* phi / golden ratio */
+#endif
 #ifndef M_PI
 #define M_PI           3.14159265358979323846  /* pi */
 #endif
 #ifndef M_SQRT1_2
 #define M_SQRT1_2      0.70710678118654752440  /* 1/sqrt(2) */
 #endif
+#ifndef M_SQRT2
+#define M_SQRT2        1.41421356237309504880  /* sqrt(2) */
+#endif
 #ifndef NAN
 #define NAN            (0.0/0.0)
 #endif
@@ -48,6 +57,12 @@
 #define INFINITY       (1.0/0.0)
 #endif
 
+/**
+ * @addtogroup lavu_math
+ * @{
+ */
+
+
 enum AVRounding {
     AV_ROUND_ZERO     = 0, ///< Round toward zero.
     AV_ROUND_INF      = 1, ///< Round away from zero.
@@ -56,23 +71,52 @@ enum AVRounding {
     AV_ROUND_NEAR_INF = 5, ///< Round to nearest and halfway cases away from zero.
 };
 
+/**
+ * Return the greatest common divisor of a and b.
+ * If both a and b are 0 or either or both are <0 then behavior is
+ * undefined.
+ */
 int64_t av_const av_gcd(int64_t a, int64_t b);
 
 /**
- * Rescales a 64-bit integer with rounding to nearest.
+ * Rescale a 64-bit integer with rounding to nearest.
  * A simple a*b/c isn't possible as it can overflow.
  */
 int64_t av_rescale(int64_t a, int64_t b, int64_t c) av_const;
 
 /**
- * Rescales a 64-bit integer with specified rounding.
+ * Rescale a 64-bit integer with specified rounding.
  * A simple a*b/c isn't possible as it can overflow.
  */
 int64_t av_rescale_rnd(int64_t a, int64_t b, int64_t c, enum AVRounding) av_const;
 
 /**
- * Rescales a 64-bit integer by 2 rational numbers.
+ * Rescale a 64-bit integer by 2 rational numbers.
  */
 int64_t av_rescale_q(int64_t a, AVRational bq, AVRational cq) av_const;
 
+/**
+ * Compare 2 timestamps each in its own timebases.
+ * The result of the function is undefined if one of the timestamps
+ * is outside the int64_t range when represented in the others timebase.
+ * @return -1 if ts_a is before ts_b, 1 if ts_a is after ts_b or 0 if they represent the same position
+ */
+int av_compare_ts(int64_t ts_a, AVRational tb_a, int64_t ts_b, AVRational tb_b);
+
+/**
+ * Compare 2 integers modulo mod.
+ * That is we compare integers a and b for which only the least
+ * significant log2(mod) bits are known.
+ *
+ * @param mod must be a power of 2
+ * @return a negative value if a is smaller than b
+ *         a positive value if a is greater than b
+ *         0                if a equals          b
+ */
+int64_t av_compare_mod(uint64_t a, uint64_t b, uint64_t mod);
+
+/**
+ * @}
+ */
+
 #endif /* AVUTIL_MATHEMATICS_H */