avutil/timecode: add function av_timecode_get_smpte()

Signed-off-by: Limin Wang <lance.lmwang@gmail.com>

libavutil/timecode.h

@@ -70,6 +70,19 @@ int av_timecode_adjust_ntsc_framenum2(int framenum, int fps);
  */
 uint32_t av_timecode_get_smpte_from_framenum(const AVTimecode *tc, int framenum);
 
+/**
+ * Convert sei info to SMPTE 12M binary representation.
+ *
+ * @param rate     frame rate in rational form
+ * @param drop     drop flag
+ * @param hh       hour
+ * @param mm       minute
+ * @param ss       second
+ * @param ff       frame number
+ * @return         the SMPTE binary representation
+ */
+uint32_t av_timecode_get_smpte(AVRational rate, int drop, int hh, int mm, int ss, int ff);
+
 /**
  * Load timecode string in buf.
  *