matroskamux: Always write a tags element into seekhead

If there are only stream tags, we still want to write the
tags entry into the seekhead, so that tags can be found
quickly in the player.

Fixes https://gitlab.freedesktop.org/gstreamer/gst-plugins-good/-/issues/905

Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-good/-/merge_requests/1020>

diff --git a/gst/matroska/matroska-mux.c b/gst/matroska/matroska-mux.c
index 48f24fd..1d003b4 100644 (file)
--- a/gst/matroska/matroska-mux.c
+++ b/gst/matroska/matroska-mux.c
@@ -3593,7 +3593,7 @@ gst_matroska_mux_finish (GstMatroskaMux * mux)
     gst_ebml_write_seek (ebml, my_pos);
   }
 
-  if (tags != NULL || toc_has_tags) {
+  if (mux->tags_pos != 0 || toc_has_tags) {
     gst_ebml_replace_uint (ebml, mux->seekhead_pos + 144,
         mux->tags_pos - mux->segment_master);
   } else {