@@ -136,6 +136,14 @@ int64_t av_rescale_q(int64_t a, AVRational bq, AVRational cq){

     return av_rescale_rnd(a, b, c, AV_ROUND_NEAR_INF);

 }

+int av_compare_ts(int64_t ts_a, AVRational tb_a, int64_t ts_b, AVRational tb_b){

+    int64_t a= tb_a.num * (int64_t)tb_b.den;

+    int64_t b= tb_b.num * (int64_t)tb_a.den;

+    if (av_rescale_rnd(ts_a, a, b, AV_ROUND_DOWN) < ts_b) return -1;

+    if (av_rescale_rnd(ts_b, b, a, AV_ROUND_DOWN) < ts_a) return  1;

+    return 0;

+}

+

 #ifdef TEST

 #include "integer.h"

 #undef printf

@@ -80,4 +80,13 @@ int64_t av_rescale_rnd(int64_t a, int64_t b, int64_t c, enum AVRounding) av_cons

  */

 int64_t av_rescale_q(int64_t a, AVRational bq, AVRational cq) av_const;

+/**

+ * Compares 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.

+ * @returns -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);

+

+

 #endif /* AVUTIL_MATHEMATICS_H */