--- src/celestia/imagecapture.cpp.orig	2014-04-26 16:15:37.185893050 +0200
+++ src/celestia/imagecapture.cpp	2014-04-26 16:16:56.697891627 +0200
@@ -31,6 +31,9 @@
 #include "png.h"
 #endif
 
+// Z_BEST_COMPRESSION
+#include <zlib.h>
+
 // Define png_jmpbuf() in case we are using a pre-1.0.6 version of libpng
 #ifndef png_jmpbuf
 #define png_jmpbuf(png_ptr) png_ptr->jmpbuf