1 files changed, 2 insertions, 0 deletions
diff --git a/demux/timeline.h b/demux/timeline.h
index 544220358a..d4a7b39403 100644
--- a/demux/timeline.h
+++ b/demux/timeline.h
@@ -35,6 +35,8 @@ struct timeline {
     struct mp_log *log;
     struct mp_cancel *cancel;
 
+    const char *format;
+
     // main source, and all other sources (this usually only has special meaning
     // for memory management; mostly compensates for the lack of refcounting)
     struct demuxer *demuxer;