GdkPixbuf, and
callback will be called. gtkClipboardRequestImage(object, callback, user.data = NULL)objectcallbackuser.datacallback.pixbuf parameter to callback will contain the resulting
GdkPixbuf if the request succeeded, or NULL if it failed. This
could happen for various reasons, in particular if the clipboard
was empty or if the contents of the clipboard could not be
converted into an image.
Since 2.6