+
+#ifdef PNG_SET_USER_LIMITS_SUPPORTED
+/* this function was added to libpng 1.2.6 */
+void PNGAPI
+png_set_user_limits (png_structp png_ptr, png_uint_32 user_width_max,
+ png_uint_32 user_height_max)
+{
+ /* Images with dimensions larger than these limits will be
+ * rejected by png_set_IHDR(). To accept any PNG datastream
+ * regardless of dimensions, set both limits to 0x7ffffffL.
+ */
+ png_ptr->user_width_max = user_width_max;
+ png_ptr->user_height_max = user_height_max;
+}
+#endif /* ?PNG_SET_USER_LIMITS_SUPPORTED */
+