Even through security information is embedded in a printed document, if the security level is changed after original data is printed, it is impossible to change the security level of a printed document. Hence, when vector data is generated from the printed document, vector data with a low security level is obtained, and that vector data can be edited and printed. Hence, a document image is read, the read image is segmented into image regions of different attributes, and pointer information embedded in each image region is extracted. An image of the image region from which no pointer information is extracted and whose vector conversion is instructed by the user is converted into vector data. A security level is set in the vector data, and the vector data set with the security level is registered in a server.