X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=libavutil%2Fmathematics.h;h=782efcca0f176d91ca6f70f38debdf09dc163c35;hb=7d9beec775b5679d1583ba2332020d9267a90156;hp=a9dfe7eccf0b4af6cc5b5b45e996d35fcf2455e1;hpb=85074d3c9388123d792995c8f98c9b5d807566b4;p=ffmpeg

diff --git a/libavutil/mathematics.h b/libavutil/mathematics.h
index a9dfe7eccf0..782efcca0f1 100644
--- a/libavutil/mathematics.h
+++ b/libavutil/mathematics.h
@@ -18,35 +18,55 @@
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
-#ifndef FFMPEG_MATHEMATICS_H
-#define FFMPEG_MATHEMATICS_H
+#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
+    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);
+
 /**
- * rescale a 64bit integer with rounding to nearest.
- * a simple a*b/c isn't possible as it can overflow
+ * 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;
 
 /**
- * rescale a 64bit integer with specified rounding.
- * a simple a*b/c isn't possible as it can overflow
+ * 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;
 
 /**
- * rescale a 64bit integer by 2 rational numbers.
+ * Rescales a 64-bit integer by 2 rational numbers.
  */
 int64_t av_rescale_q(int64_t a, AVRational bq, AVRational cq) av_const;
 
-#endif /* FFMPEG_MATHEMATICS_H */
+#endif /* AVUTIL_MATHEMATICS_H */