--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lib/libavutil/mathematics.h	Tue Dec 31 14:52:14 2013 +0000
@@ -0,0 +1,147 @@
+/*
+ * copyright (c) 2005-2012 Michael Niedermayer <michaelni@gmx.at>
+ *
+ * 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 2.1 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
+ */
+
+#ifndef AVUTIL_MATHEMATICS_H
+#define AVUTIL_MATHEMATICS_H
+
+#include <stdint.h>
+#include <math.h>
+#include "attributes.h"
+#include "rational.h"
+#include "intfloat.h"
+
+#ifndef M_E
+#define M_E            2.7182818284590452354   /* e */
+#endif
+#ifndef M_LN2
+#define M_LN2          0.69314718055994530942  /* log_e 2 */
+#endif
+#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            av_int2float(0x7fc00000)
+#endif
+#ifndef INFINITY
+#define INFINITY       av_int2float(0x7f800000)
+#endif
+
+/**
+ * @addtogroup lavu_math
+ * @{
+ */
+
+
+enum AVRounding {
+    AV_ROUND_ZERO     = 0, ///< Round toward zero.
+    AV_ROUND_INF      = 1, ///< Round away from zero.
+    AV_ROUND_DOWN     = 2, ///< Round toward -infinity.
+    AV_ROUND_UP       = 3, ///< Round toward +infinity.
+    AV_ROUND_NEAR_INF = 5, ///< Round to nearest and halfway cases away from zero.
+    AV_ROUND_PASS_MINMAX = 8192, ///< Flag to pass INT64_MIN/MAX through instead of rescaling, this avoids special cases for AV_NOPTS_VALUE
+};
+
+/**
+ * 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);
+
+/**
+ * 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;
+
+/**
+ * Rescale a 64-bit integer with specified rounding.
+ * A simple a*b/c isn't possible as it can overflow.
+ *
+ * @return rescaled value a, or if AV_ROUND_PASS_MINMAX is set and a is
+ *         INT64_MIN or INT64_MAX then a is passed through unchanged.
+ */
+int64_t av_rescale_rnd(int64_t a, int64_t b, int64_t c, enum AVRounding) av_const;
+
+/**
+ * Rescale a 64-bit integer by 2 rational numbers.
+ */
+int64_t av_rescale_q(int64_t a, AVRational bq, AVRational cq) av_const;
+
+/**
+ * Rescale a 64-bit integer by 2 rational numbers with specified rounding.
+ *
+ * @return rescaled value a, or if AV_ROUND_PASS_MINMAX is set and a is
+ *         INT64_MIN or INT64_MAX then a is passed through unchanged.
+ */
+int64_t av_rescale_q_rnd(int64_t a, AVRational bq, AVRational cq,
+                         enum AVRounding) 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);
+
+/**
+ * Rescale a timestamp while preserving known durations.
+ *
+ * @param in_ts Input timestamp
+ * @param in_tb Input timesbase
+ * @param fs_tb Duration and *last timebase
+ * @param duration duration till the next call
+ * @param out_tb Output timesbase
+ */
+int64_t av_rescale_delta(AVRational in_tb, int64_t in_ts,  AVRational fs_tb, int duration, int64_t *last, AVRational out_tb);
+
+/**
+ * @}
+ */
+
+#endif /* AVUTIL_MATHEMATICS_H */