/* If you define PNGAPI, e.g., with compiler option "-DPNGAPI=__stdcall",
* you may get warnings regarding the linkage of png_zalloc and png_zfree.
/* If you define PNGAPI, e.g., with compiler option "-DPNGAPI=__stdcall",
* you may get warnings regarding the linkage of png_zalloc and png_zfree.