Print control method using electronic watermark information

A print control method comprising the steps of:

• receiving a print request and image data;
• generating identifying information unique to the received print order and the image data;
• embedding electronic watermark information indicating the identifying information in the image data;
• storing the image data in which the electronic watermark information has been embedded into a storage medium by associating the image data with the identifying information;
• outputting the image data in which the electronic watermark information has been embedded to a print unit;
• judging whether or not the identifying information is included in the print request received in said receiving step;
• reading image data related to the identifying information from the storage medium when it is judged that the identifying information is included and outputting the image data to the print unit;
• wherein said reprint control step transmits information related to the previous print request corresponding to the identifying information to a sender of the print request.

A print control method for a print control system having a center server and a client comprising the steps of:

• performing the following steps by the center server:
• receiving a print request and image data from the client;
• generating identifying information unique to the received print order and the image data;
• embedding electronic watermark information indicating the identifying information in the image data;
• storing the image data in which the electronic watermark information has been embedded into a storage medium by associating the image data with the identifying information;
• outputting the image data in which the electronic watermark information has been embedded to a print unit;
• judging whether or not the identifying information is included in the print request received in said receiving step;
• and
• reading image data related to the identifying information from the storage medium when it is judged that the identifying information is included and outputting the image data to the print unit and transmitting information related to the previous print request corresponding to the identifying information to the client;
• and
• performing the following steps by the client:
• extracting electronic watermark information embedded in a print;
• transmitting the extracted electronic watermark information to the center server;
• receiving information related to the previous print request corresponding to the electronic watermark information from the center server;
• displaying information related to a received print request;
• and
• transmitting a reprint request to the center server,
• wherein the reprint request is obtained by updating a content of the received print request.

A computer-readable storage medium which stores a program for causing an image processing apparatus of processing image data to be printed in accordance with a print request from an external to execute the following steps of:

• receiving a print request and image data;
• generating identifying information unique to the received print order and the image data;
• embedding electronic watermark information indicating the identifying information in the image data;
• storing the image data in which the electronic watermark information has been embedded into a storage medium by associating the image data with the identifying information;
• outputting the image data in which the electronic watermark information has been embedded to a print unit;
• judging whether or not the identifying information is included in the print request received in said receiving step;
• and
• reading image data related to the identifying information from the storage medium when it is judged that the identifying information is included and outputting the image data to the print unit,
• wherein said reprint control step transmits information related to the previous print request corresponding to the identifying information to a sender of the print request.