diff --git a/src/libpng/pngconf.h b/src/libpng/pngconf.h
index 0b118af42..f65665621 100644
--- a/src/libpng/pngconf.h
+++ b/src/libpng/pngconf.h
@@ -50,6 +50,15 @@
 #  include "pngusr.h"
 #endif
 
+/*
+ * Added by stephena - 2010/06/17
+ *
+ * Disable parts of the library that we know Stella will never use.
+ */
+#define PNG_NO_MNG_FEATURES
+#define PNG_NO_PROGRESSIVE_READ
+#define PNG_PROGRESSIVE_READ_NOT_SUPPORTED
+
 /*
  * If you create a private DLL you need to define in "pngusr.h" the followings:
  * #define PNG_USER_PRIVATEBUILD <Describes by whom and why this version of