timecodestamper: Validate LTC timestamps before trying to use them

There's no point in working with invalid LTC timestamps as all future
calculations will be wrong based on this, and invalid LTC timestamps can
sometimes be read via the audio input.

diff --git a/gst/timecode/gsttimecodestamper.c b/gst/timecode/gsttimecodestamper.c
index a3098a2..cd357f4 100644 (file)
--- a/gst/timecode/gsttimecodestamper.c
+++ b/gst/timecode/gsttimecodestamper.c
@@ -1089,10 +1089,17 @@ gst_timecodestamper_transform_ip (GstBaseTransform * vfilter,
         if (timecodestamper->ltc_auto_resync) {
           if (timecodestamper->ltc_internal_tc)
             gst_video_time_code_free (timecodestamper->ltc_internal_tc);
-          timecodestamper->ltc_internal_tc =
-              gst_video_time_code_copy (ltc_read_tc_ptr);
-          updated_internal = TRUE;
-          GST_INFO_OBJECT (timecodestamper, "Resynced internal LTC counter");
+          if (gst_video_time_code_is_valid (ltc_read_tc_ptr)) {
+            timecodestamper->ltc_internal_tc =
+                gst_video_time_code_copy (ltc_read_tc_ptr);
+            updated_internal = TRUE;
+            GST_INFO_OBJECT (timecodestamper, "Resynced internal LTC counter");
+          } else {
+            tc_str = gst_video_time_code_to_string (ltc_read_tc_ptr);
+            GST_INFO_OBJECT (timecodestamper, "Invalid LTC timecode %s",
+                tc_str);
+            g_free (tc_str);
+          }
         }
 
         /* And store it for the next frame in case it has more or less the