diff --git a/cam2ip.go b/cam2ip.go
index 3d3bd95..91bf202 100644
--- a/cam2ip.go
+++ b/cam2ip.go
@@ -1,3 +1,5 @@
+// +build !cv2,!cv4
+
 package main
 
 import (
diff --git a/cam2ip_cv.go b/cam2ip_cv.go
index 0a40ae6..4c209db 100644
--- a/cam2ip_cv.go
+++ b/cam2ip_cv.go
@@ -1,4 +1,4 @@
-// +build cv2,cv4
+// +build cv2 cv4
 
 package main