avutil/timecode: fix av_timecode_get_smpte_from_framenum with 50/60 fps

[ffmpeg] / libavutil / timecode.h

diff --git a/libavutil/timecode.h b/libavutil/timecode.h
index 37c1361bc281ad6bf52d2ae0315fe32148389847..e54b116e93b556b91c70bf6e6e05c782a5fd4262 100644 (file)
--- a/libavutil/timecode.h
+++ b/libavutil/timecode.h
@@ -62,14 +62,39 @@ int av_timecode_adjust_ntsc_framenum2(int framenum, int fps);
  * @param framenum frame number
  * @return         the SMPTE binary representation
  *
+ * See SMPTE ST 314M-2005 Sec 4.4.2.2.1 "Time code pack (TC)"
+ * the format description as follows:
+ * bits 0-5:   hours, in BCD(6bits)
+ * bits 6:     BGF1
+ * bits 7:     BGF2 (NTSC) or FIELD (PAL)
+ * bits 8-14:  minutes, in BCD(7bits)
+ * bits 15:    BGF0 (NTSC) or BGF2 (PAL)
+ * bits 16-22: seconds, in BCD(7bits)
+ * bits 23:    FIELD (NTSC) or BGF0 (PAL)
+ * bits 24-29: frames, in BCD(6bits)
+ * bits 30:    drop  frame flag (0: non drop,    1: drop)
+ * bits 31:    color frame flag (0: unsync mode, 1: sync mode)
+ * @note BCD numbers (6 or 7 bits): 4 or 5 lower bits for units, 2 higher bits for tens.
  * @note Frame number adjustment is automatically done in case of drop timecode,
  *       you do NOT have to call av_timecode_adjust_ntsc_framenum2().
  * @note The frame number is relative to tc->start.
- * @note Color frame (CF), binary group flags (BGF) and biphase mark polarity
- *       correction (PC) bits are set to zero.
+ * @note Color frame (CF) and binary group flags (BGF) bits are set to zero.
  */
 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.
  *