avfilter/vf_showinfo: display GOP timecode side data

Signed-off-by: Limin Wang <lance.lmwang@gmail.com>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

libavfilter/vf_showinfo.c

@@ -313,6 +313,12 @@ static int filter_frame(AVFilterLink *inlink, AVFrame *frame)
         case AV_FRAME_DATA_CONTENT_LIGHT_LEVEL:
             dump_content_light_metadata(ctx, sd);
             break;
+        case AV_FRAME_DATA_GOP_TIMECODE: {
+            char tcbuf[AV_TIMECODE_STR_SIZE];
+            av_timecode_make_mpeg_tc_string(tcbuf, *(int64_t *)(sd->data));
+            av_log(ctx, AV_LOG_INFO, "GOP timecode - %s", tcbuf);
+            break;
+        }
         default:
             av_log(ctx, AV_LOG_WARNING, "unknown side data type %d (%d bytes)",
                    sd->type, sd->size);