diff --git a/src/zm_event.h b/src/zm_event.h
index 3b6caa470..83dccf84c 100644
--- a/src/zm_event.h
+++ b/src/zm_event.h
@@ -53,6 +53,8 @@ protected:
 	static int		sd;
 
 protected:
+    typedef enum { NORMAL, BULK, ALARM } FrameType;
+
 	struct PreAlarmData
 	{
 		Image *image;