diff --git a/ArcFormats/ImageZBM.cs b/ArcFormats/ImageZBM.cs
index 2c32aa62..dc7c6f8b 100644
--- a/ArcFormats/ImageZBM.cs
+++ b/ArcFormats/ImageZBM.cs
@@ -24,10 +24,8 @@
 //
 
 using System;
-using System.Collections.Generic;
 using System.ComponentModel.Composition;
 using System.IO;
-using System.Runtime.InteropServices;
 using GameRes.Utility;
 
 namespace GameRes.Formats.Crowd