+ * @return (AVRational) d
+ */
+AVRational av_d2q(double d, int max) av_const;
+
+/**
+ * @return 1 if q1 is nearer to q than q2, -1 if q2 is nearer
+ * than q1, 0 if they have the same distance.
+ */
+int av_nearer_q(AVRational q, AVRational q1, AVRational q2);
+
+/**
+ * Find the nearest value in q_list to q.
+ * @param q_list an array of rationals terminated by {0, 0}
+ * @return the index of the nearest value found in the array
+ */
+int av_find_nearest_q_idx(AVRational q, const AVRational* q_list);
+
+/**
+ * @}