c_gdk_pixbuf_add_alpha

Undocumented in source but is binding to C. You might be able to learn more by searching the web for its name.
__gshared extern (C)
GdkPixbuf* function(GdkPixbuf* pixbuf, int substituteColor, char r, char g, char b) c_gdk_pixbuf_add_alpha;

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