diff --git a/test/video_source.h b/test/video_source.h
index 8739dda..ade323e 100644
--- a/test/video_source.h
+++ b/test/video_source.h
@@ -11,6 +11,7 @@
 #define TEST_VIDEO_SOURCE_H_
 
 #if defined(_WIN32)
+#undef NOMINMAX
 #define NOMINMAX
 #define WIN32_LEAN_AND_MEAN
 #include <windows.h>