avutil: add av_rescale_q_rnd() to allow different rounding

doc/APIchanges

@@ -13,6 +13,9 @@ libavutil:   2011-04-18
 
 API changes, most recent first:
 
+2012-02-xx - xxxxxxx - lavu 51.23.1 - mathematics.h
+  Add av_rescale_q_rnd()
+
 2012-02-xx - xxxxxxx - lavu 51.22.1 - pixdesc.h
   Add PIX_FMT_PSEUDOPAL flag.
 

libavutil/avutil.h

@@ -154,7 +154,7 @@
  */
 
 #define LIBAVUTIL_VERSION_MAJOR 51
-#define LIBAVUTIL_VERSION_MINOR 22
+#define LIBAVUTIL_VERSION_MINOR 23
 #define LIBAVUTIL_VERSION_MICRO  1
 
 #define LIBAVUTIL_VERSION_INT   AV_VERSION_INT(LIBAVUTIL_VERSION_MAJOR, \

libavutil/mathematics.c

@@ -130,10 +130,17 @@ int64_t av_rescale(int64_t a, int64_t b, int64_t c){
     return av_rescale_rnd(a, b, c, AV_ROUND_NEAR_INF);
 }
 
-int64_t av_rescale_q(int64_t a, AVRational bq, AVRational cq){
+int64_t av_rescale_q_rnd(int64_t a, AVRational bq, AVRational cq,
+                         enum AVRounding rnd)
+{
     int64_t b= bq.num * (int64_t)cq.den;
     int64_t c= cq.num * (int64_t)bq.den;
-    return av_rescale_rnd(a, b, c, AV_ROUND_NEAR_INF);
+    return av_rescale_rnd(a, b, c, rnd);
+}
+
+int64_t av_rescale_q(int64_t a, AVRational bq, AVRational cq)
+{
+    return av_rescale_q_rnd(a, bq, cq, AV_ROUND_NEAR_INF);
 }
 
 int av_compare_ts(int64_t ts_a, AVRational tb_a, int64_t ts_b, AVRational tb_b){

libavutil/mathematics.h

@@ -95,6 +95,12 @@ 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;
 
+/**
+ * Rescale a 64-bit integer by 2 rational numbers with specified rounding.
+ */
+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