--- /dev/null
+/*
+ * copyright (c) 2005 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 "common.h"
+#include "rational.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_PI
+#define M_PI 3.14159265358979323846 /* pi */
+#endif
+#ifndef M_SQRT1_2
+#define M_SQRT1_2 0.70710678118654752440 /* 1/sqrt(2) */
+#endif
+
+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.
+};
+
+int64_t av_const av_gcd(int64_t a, int64_t b);
+
+/**
+ * Rescales 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.
+ * 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.
+ */
+int64_t av_rescale_q(int64_t a, AVRational bq, AVRational cq) av_const;
+
+#endif /* AVUTIL_MATHEMATICS_H */