--- /dev/null
+/*
+ * 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_PI_2
+#define M_PI_2 1.57079632679489661923 /* pi/2 */
+#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
+};
+
+/**
+ * Compute the greatest common divisor of a and b.
+ *
+ * @return gcd of a and b up to sign; if a >= 0 and b >= 0, return value is >= 0;
+ * if a == 0 and b == 0, returns 0.
+ */
+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 timebase
+ * @param fs_tb Duration and *last timebase
+ * @param duration duration till the next call
+ * @param out_tb Output timebase
+ */
+int64_t av_rescale_delta(AVRational in_tb, int64_t in_ts, AVRational fs_tb, int duration, int64_t *last, AVRational out_tb);
+
+/**
+ * Add a value to a timestamp.
+ *
+ * This function guarantees that when the same value is repeatly added that
+ * no accumulation of rounding errors occurs.
+ *
+ * @param ts Input timestamp
+ * @param ts_tb Input timestamp timebase
+ * @param inc value to add to ts
+ * @param inc_tb inc timebase
+ */
+int64_t av_add_stable(AVRational ts_tb, int64_t ts, AVRational inc_tb, int64_t inc);
+
+
+ /**
+ * @}
+ */
+
+#endif /* AVUTIL_MATHEMATICS_H */
projects / rtmpclient.git / blobdiff