--- a/Core/FileFormats/PngWriter.cpp	Wed Oct 30 11:56:28 2013 +0100
+++ b/Core/FileFormats/PngWriter.cpp	Mon Nov 04 11:19:31 2013 +0100
@@ -231,7 +231,7 @@
                              png_bytep data, 
                              png_size_t size)
   {
-    ChunkedBuffer* buffer = (ChunkedBuffer*) png_get_io_ptr(png_ptr);
+    ChunkedBuffer* buffer = reinterpret_cast<ChunkedBuffer*>(png_get_io_ptr(png_ptr));
     buffer->AddChunk(reinterpret_cast<const char*>(data), size);
   }