mpegtspacketizer: Use first group for handling reference pcr

If _set_current_pcr_offset gets called after a flushing seek, we ended
up using the current group for delta calculation ... whereas we should
be using the first group to calculate shifts.

Also add an early exit if there are no changes to apply

diff --git a/gst/mpegtsdemux/mpegtspacketizer.c b/gst/mpegtsdemux/mpegtspacketizer.c
index fe657556cec8436b4e71faa59aef8810e63dbf1d..7785711fca898977d553a3532a3a31a12ec542e8 100644 (file)
--- a/gst/mpegtsdemux/mpegtspacketizer.c
+++ b/gst/mpegtsdemux/mpegtspacketizer.c
@@ -2364,7 +2364,11 @@ mpegts_packetizer_set_current_pcr_offset (MpegTSPacketizer2 * packetizer,
 
   pcr_offset = GSTTIME_TO_PCRTIME (offset);
 
-  group = pcrtable->current->group;
+  /* Pick delta from *first* group */
+  if (pcrtable->groups)
+    group = pcrtable->groups->data;
+  else
+    group = pcrtable->current->group;
   GST_DEBUG ("Current group PCR %" GST_TIME_FORMAT " (offset %"
       G_GUINT64_FORMAT " pcr_offset %" GST_TIME_FORMAT,
       GST_TIME_ARGS (PCRTIME_TO_GSTTIME (group->first_pcr)),
@@ -2374,6 +2378,10 @@ mpegts_packetizer_set_current_pcr_offset (MpegTSPacketizer2 * packetizer,
   /* Remember the difference between previous initial pcr_offset and
    * new initial pcr_offset */
   delta = pcr_offset - group->pcr_offset;
+  if (delta == 0) {
+    GST_DEBUG ("No shift to apply");
+    return;
+  }
   GST_DEBUG ("Shifting groups by %" GST_TIME_FORMAT
       " for new initial pcr_offset %" GST_TIME_FORMAT,
       GST_TIME_ARGS (PCRTIME_TO_GSTTIME (delta)), GST_TIME_ARGS (offset));