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authorgiraffedata <giraffedata@9d0c8265-081b-0410-96cb-a4ca84ce46f8>2016-09-26 16:47:30 +0000
committergiraffedata <giraffedata@9d0c8265-081b-0410-96cb-a4ca84ce46f8>2016-09-26 16:47:30 +0000
commitd211a02b3c636e19d6029700acb42c7a47da3dbc (patch)
tree1b429f1b9542e46b5bd0f64f05c315808b8283da /converter
parent3e9e37b8c06f462ab4eb055109b73ca5a76fd47c (diff)
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git-svn-id: http://svn.code.sf.net/p/netpbm/code/trunk@2822 9d0c8265-081b-0410-96cb-a4ca84ce46f8
Diffstat (limited to 'converter')
-rw-r--r--converter/other/pngx.h4
1 files changed, 4 insertions, 0 deletions
diff --git a/converter/other/pngx.h b/converter/other/pngx.h
index cabb0663..008081eb 100644
--- a/converter/other/pngx.h
+++ b/converter/other/pngx.h
@@ -2,6 +2,10 @@
 #define PNGX_H_INCLUDED
 
 #include <png.h>
+    /* This includes the Zlib interface header file zlib.h because libpng uses
+       libz and some of the Zlib interface, e.g. the Z_DEFLATED constant,
+       is part of the libpng interface.
+    */
 #include "pm_c_util.h"
 
 /* pngx is designed to be an extension of the PNG library to make using