iface->get_n_pages = ps_document_get_n_pages;
iface->get_page_size = ps_document_get_page_size;
iface->render_pixbuf = ps_document_render_pixbuf;
iface->get_n_pages = ps_document_get_n_pages;
iface->get_page_size = ps_document_get_page_size;
iface->render_pixbuf = ps_document_render_pixbuf;