This patch comes from the Debian package.

Index: pnglite-0.1.17/pnglite.h
===================================================================
--- pnglite-0.1.17.orig/pnglite.h	2008-04-18 17:15:07.000000000 +1000
+++ pnglite-0.1.17/pnglite.h	2008-04-18 17:15:18.000000000 +1000
@@ -24,7 +24,8 @@
 	daniel.karling@gmail.com
  */
 
-
+
+#include <stdio.h>
 #ifndef _PNGLITE_H_
 #define _PNGLITE_H_