Information processing apparatus, information processing method, and computer readable storage medium

• US 7,706,568 B2
• Filed: 08/24/2006
• Issued: 04/27/2010
• Est. Priority Date: 09/08/2005
• Status: Expired due to Fees

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Yamazaki, Taeko, Hayashi, Junichi
• Primary Examiner(s): KIM, CHONG R
• Application Number:
  US11/466,869
• Publication Number:
  US 20070055885A1
• Time in Patent Office: 1,342 Days
• Field of Search: None
• US Class Current: 382/100
• CPC Class Codes: G06F 21/64 Protecting data integrity, e.g. using checksums, certificates or signatures
• CPC Class Codes: H04L 2209/68 Special signature format, e.g. XML format
• CPC Class Codes: H04L 9/3247 involving digital signatures

Abstract

A method is provided that enables verification of whether a component of original image data has been altered at the location at which the component is to be reused without newly generating a signature. More specifically, the method includes inputting first document data including a plurality of components and signature information corresponding to the components, selecting at least one component from among the components, and extracting signature information corresponding to the at least one selected component. The method further includes storing the at least one selected component and the signature information corresponding to the at least one selected component in a memory, and generating second document data by pasting the at least one stored component and the stored signature information into a document selected as a paste location.

Claims

1. A method comprising:

inputting first document data including a plurality of components and signature information corresponding to each of the components, wherein the signature information is calculated according to a digest value of a corresponding component and a private key, and wherein the plurality of components comprise at least document information and transmission information, wherein the document information comprises at least one of an attribute, layout information, character code string, and document logical construction, and wherein the transmission information comprises information required for rendering processing;

selecting at least one component from among the plurality of components;

extracting signature information corresponding to the at least one selected component;

storing the at least one selected component and the signature information corresponding to the at least one selected component separately in a memory; and

generating second document data by pasting the at least one stored component and the stored signature information,

wherein the signature information includes pointer information corresponding to the at least one selected component, and

wherein the extracting step comprises extracting the pointer information.

2. The method according to claim 1, wherein the generating step comprises:

selecting an electronic document; and

pasting the at least one stored component and the stored signature information into the selected electronic document.

3. The method according to claim 1,

wherein the first document data includes a table indicating correspondence between each of the plurality of components and the signature information corresponding to the components, and

wherein the signature information corresponding to the at least one selected component is extracted from the table.

4. An information processing apparatus comprising:

an input unit to input first document data including a plurality of components and signature information corresponding to each of the components, wherein the signature information is calculated according to a digest value of a corresponding component and a private key, and wherein the plurality of components comprise at least document information and transmission information, wherein the document information comprises at least one of an attribute, layout information, character code string, and document logical construction, and wherein the transmission information comprises information required for rendering processing;

a selecting unit to select at least one component from among the components;

an extracting unit to extract signature information corresponding to the at least one selected component;

a storing unit to store the at least one selected component and the signature information corresponding to the at least one selected component separately; and

a generating unit to generate second document data by pasting the at least one stored component and the stored signature information,

wherein the signature information includes pointer information corresponding to the at least one selected component, and

wherein the extracting step comprises extracting the pointer information.

5. The information processing apparatus according to claim 4, wherein the generating unit generates the second document data by selecting an electronic document and pasting the at least one stored component and the stored signature information into the selected electronic document.

6. The information processing apparatus according to claim 4,

wherein the first document data includes a table indicating correspondence each of the plurality of components and the signature information corresponding to the components, and

wherein the extracting unit extracts the signature information corresponding to the at least one selected component from the table.

7. A computer readable storage medium storing instructions which, when executed by a computer, causes the computer to perform operations comprising:

receiving first document data including a plurality of components and signature information corresponding to each of the components, wherein the signature information is calculated according to a digest value of a corresponding component and a private key, and wherein the plurality of components comprise at least document information and transmission information, wherein the document information comprises at least one of an attribute, layout information, character code string, and document logical construction, and wherein the transmission information comprises information required for rendering processing;

selecting at least one component from among the components;

extracting signature information corresponding to the at least one selected component;

storing the at least one selected component and the signature information corresponding to the at least one selected component separately in a memory; and

generating second document data by pasting the at least one stored component and the stored signature information,

wherein the signature information includes pointer information corresponding to the at least one selected component, and

wherein the extracting step comprises extracting the pointer information.

8. The computer readable storage medium of claim 7, wherein the generating step comprises:

selecting an electronic document; and

pasting the at least one stored component and the stored signature information into the selected electronic document.