lavc/h264: create AVFrame side data from H.264 timecodes

Create SMPTE ST 12-1 timecodes based on H.264 SEI picture timing
info.

For framerates > 30 FPS, the field flag is used in conjunction with
pairs of frames which contain the same frame timestamp in S12M.
Ensure the field is properly set per the spec.

2 files changed, 9 insertions, 0 deletions

diff --git a/libavutil/frame.c b/libavutil/frame.c
index 4460325a9b..92626dccf2 100644
--- a/libavutil/frame.c
+++ b/libavutil/frame.c
@@ -831,6 +831,7 @@ const char *av_frame_side_data_name(enum AVFrameSideDataType type)
     case AV_FRAME_DATA_MASTERING_DISPLAY_METADATA:  return "Mastering display metadata";
     case AV_FRAME_DATA_CONTENT_LIGHT_LEVEL:         return "Content light level metadata";
     case AV_FRAME_DATA_GOP_TIMECODE:                return "GOP timecode";
+    case AV_FRAME_DATA_S12M_TIMECODE:               return "SMPTE 12-1 timecode";
     case AV_FRAME_DATA_SPHERICAL:                   return "Spherical Mapping";
     case AV_FRAME_DATA_ICC_PROFILE:                 return "ICC profile";
 #if FF_API_FRAME_QP
diff --git a/libavutil/frame.h b/libavutil/frame.h
index 9d57d6ce66..e2a292980f 100644
--- a/libavutil/frame.h
+++ b/libavutil/frame.h
@@ -158,6 +158,14 @@ enum AVFrameSideDataType {
      */
     AV_FRAME_DATA_QP_TABLE_DATA,
 #endif
+
+    /**
+     * Timecode which conforms to SMPTE ST 12-1. The data is an array of 4 uint32_t
+     * where the first uint32_t describes how many (1-3) of the other timecodes are used.
+     * The timecode format is described in the av_timecode_get_smpte_from_framenum()
+     * function in libavutil/timecode.c.
+     */
+    AV_FRAME_DATA_S12M_TIMECODE,
 };
 
 enum AVActiveFormatDescription {