IMAGE PROCESSING METHOD, IMAGE PROCESSING APPARATUS, IMAGE READING APPARATUS, AND IMAGE FORMING APPARATUS

• US 20080212115A1
• Filed: 02/06/2008
• Published: 09/04/2008
• Est. Priority Date: 02/13/2007
• Status: Active Grant

• Current Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Original Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Inventors: KONISHI, Yohsuke
• Granted Patent: US 8,320,683 B2
• Time in Patent Office: Days
• US Class Current: 358/1.9
• CPC Class Codes: G06V 30/10 Character recognition
• CPC Class Codes: G06V 30/18143 Extracting features based on salient regional features, e.g. scale invariant feature transform [SIFT] keypoints
• CPC Class Codes: G06V 30/40 Document-oriented image-based pattern recognition
• CPC Class Codes: H04N 1/2166 for mass storage, e.g. in document filing systems information retrieval G06F16/00
• CPC Class Codes: H04N 1/32112 in a separate computer file, document page or paper sheet, e.g. a fax cover sheet H04N1/32122 takes precedence
• CPC Class Codes: H04N 2201/3232 of a page, copy or picture number
• CPC Class Codes: H04N 2201/3238 using a coded or compressed version of the image data itself
• CPC Class Codes: H04N 2201/3243 of type information, e.g. handwritten or text document

Abstract

When a reference image to which a document image is judged as being similar for the first time is not the first document sheet of the document type which contains this reference image, error occurrence is concluded so that the page number indicated by a counter is set to be an error occurrence position. In case that the reference image to which the document image is similar is the last document sheet of the document type, when the number of document images having been counted up by the time when this document image is judged as being similar to the reference image does not correspond with the number of reference images contained in the document type, error occurrence is concluded so that the page number indicated by a counter is set to be an error occurrence position.

Claims

1. An image processing method for judging whether an obtained document image is similar to a preliminary reference image and then, on the basis of the judgment result, performing image processing on the document image, comprising:

a step of storing a plurality of type identifiers each of which contains one or a plurality of image identifiers each for identifying each of a plurality of reference images and thereby identifies a type of a document;

a judgment step of judging whether the obtained document image is similar to a reference image;

a selection step of, when the document image is judged as being similar to a reference image in said judgment step, selecting an image identifier which identifies the reference image from among the stored image identifiers; and

a determination step of, for each type identifier which contains the image identifier selected in said selection step, determining whether the image identifier contained in the type identifier corresponds with the image identifier which identifies the reference image judged as being similar to the document image.

2. The image processing method according to claim 1, wherein

the image identifier contains an identifier which indicates whether the reference image is the first reference image contained in the document type identified by the type identifier which contains the image identifier itself, and wherein

said image processing method further comprises:

a step of, at each time when a document image is judged as being similar to a reference image, counting up the number of document images for the document images judged as being similar; and

a step of, when the first sheet is counted up, determining whether the reference image is the first reference image on the basis of the image identifier selected in said selection step;

wherein

when the reference image is determined as not being the first reference image, said determination step determines that the order of the document identified by the type identifier which contains the image identifier selected in said selection step does not correspond with the order of the document having been stored.

3. The image processing method according to claim 1, wherein

the image identifier contains an identifier which indicates whether the reference image is the last reference image contained in the document type identified by the type identifier which contains the image identifier itself, and wherein

said image processing method further comprises:

a step of, at each time when a document image is judged as being similar to a reference image, counting up the number of document images for the document images judged as being similar;

a step of, when said judgment step judges that the document image is similar to the reference image, determining whether the reference image is the last reference image on the basis of the image identifier selected in said selection step; and

a step of, when the reference image is determined as being the last reference image, determining whether the number of counted document images corresponds with the number of image identifiers contained in the type identifier which contains the image identifier selected in said selection step;

wherein

when the number of counted document images is determined as not corresponding with the number of image identifiers contained in the type identifier, said determination step determines that the order of the document identified by the type identifier which contains the image identifier selected in said selection step does not correspond with the order of the document having been stored.

4. The image processing method according to claim 1, wherein

the image identifier contains an identifier which indicates a page number in the document type identified by the type identifier containing the image identifier itself, and wherein

said image processing method further comprises:

a step of, at each time when a document image is judged as being similar to a reference image, counting up the number of document images for the document images judged as being similar;

a step of, when said judgment step judges that the document image is similar to the reference image, detecting the page number of the reference image on the basis of the image identifier selected in said selection step; and

a step of determining whether the detected page number corresponds with the number of counted document images;

wherein

when the detected page number is determined as not corresponding with the number of counted document images, said determination step determines that the order of the document identified by the type identifier which contains the image identifier selected in said selection step does not correspond with the order of the document having been stored.

5. The image processing method according to claim 1, wherein

the image identifier contains an identifier which indicates that the image is either a front side image or a back side image of one document sheet,

said judgment step judges whether two document images obtained from the front side and the back side of the one document sheet are respectively similar to reference images, and

when said judgment step judges that the two document images are respectively similar to reference images, said selection step selects image identifiers each of which identifies the reference image from among the stored image identifiers, and wherein

said image processing method further comprises:

a step of, on the basis of the image identifier selected in said selection step, determining whether the two reference images are the front side image and the back side image of the one document sheet; and

a step of, when the two reference images are determined as being the front side image and the back side image of the one document sheet, determining whether the reference image similar to the document image obtained from the front side of the one document sheet is the front side image and whether the reference image similar to the document image obtained from the back side of the one document sheet is the back side image;

wherein

when it is determined that the reference image similar to the document image obtained from the front side of the one document sheet is the back side image and that the reference image similar to the document image obtained from the back side of the one document sheet is the front side image, said determination step determines that the order of the document identified by the type identifier which contains the image identifier selected in said selection step does not correspond with the order of the document having been stored.

6. The image processing method according to claim 5, further comprising:

a step of, when it is determined that the reference image similar to the document image obtained from the front side of the one document sheet is the back side image and that the reference image similar to the document image obtained from the back side of the one document sheet is the front side image, exchanging the front and back of the two document images.

7. The image processing method according to claim 1, further comprising:

a step of storing features as associated with an image identifier of the reference image; and

an extraction step of extracting features of the obtained document image;

wherein

on the basis of the features extracted in said extraction step and the stored features of the reference image, said judgment step judges whether the document image is similar to the reference image.

8. The image processing method according to claim 1, further comprising

a step of notifying a situation when said determination step determines that the order of the document identified by the type identifier which contains the image identifier selected in said selection step does not correspond with the order of the document having been stored.

9. An image processing apparatus for judging whether an obtained document image is similar to a preliminary reference image and then, on the basis of the judgment result, performing image processing on the document image, comprising:

a storage section for storing a plurality of type identifiers each of which contains one or a plurality of image identifiers each for identifying each of a plurality of reference images and thereby identifies a type of a document;

a judgment section for judging whether the obtained document image is similar to a reference image;

a selection section for, when said judgment section judges that the document image is similar to a reference image, selecting an image identifier which identifies the reference image from among the image identifiers stored in said storage section; and

a first determination section for, for each type identifier which contains the image identifier selected by said selection section, determining whether the image identifier contained in the type identifier corresponds with the image identifier which identifies the reference image judged as being similar to the document image.

10. The image processing apparatus according to claim 9, wherein

the image identifier contains an identifier which indicates whether the reference image is the first reference image contained in the document type identified by the type identifier which contains the image identifier itself, and wherein

said image processing apparatus further comprises:

a counting section for, at each time when a document image is judged as being similar to a reference image, counting up the number of document images judged as being similar; and

a second determination section for, when the first sheet is counted up, determining whether the reference image is the first reference image on the basis of the image identifier selected by said selection section;

wherein

when the reference image is determined as not being the first reference image, said first determination section determines that the order of the document identified by the type identifier which contains the image identifier selected by said selection section does not correspond with the order of the document having been stored.

11. The image processing apparatus according to claim 9, wherein

the image identifier contains an identifier which indicates whether the reference image is the last reference image contained in the document type identified by the type identifier which contains the image identifier itself, and wherein

said image processing apparatus further comprises:

a counting section for, at each time when a document image is judged as being similar to a reference image, counting up the number of document images judged as being similar;

a third determination section for, when said judgment section judges that the document image is similar to the reference image, determining whether the reference image is the last reference image on the basis of the image identifier selected by said selection section; and

a fourth determination section for, when the reference image is determined as being the last reference image, determining whether the number of counted document images corresponds with the number of image identifiers contained in the type identifier which contains the image identifier selected by said selection section;

wherein

when the number of counted document images is determined as not corresponding with the number of image identifiers contained in the type identifier, said first determination section determines that the order of the document identified by the type identifier which contains the image identifier selected by said selection section does not correspond with the order of the document having been stored.

12. The image processing apparatus according to claim 9, wherein

the image identifier contains an identifier which indicates a page number in the document type identified by the type identifier containing the image identifier itself, and wherein

said image processing apparatus further comprises:

a counting section for, at each time when a document image is judged as being similar to a reference image, counting up the number of document images judged as being similar;

a detecting section for, when said judgment section judges that the document image is similar to the reference image, detecting the page number of the reference image on the basis of the image identifier selected by said selection section; and

a fifth determination section for determining whether the detected page number corresponds with the number of counted document images;

wherein

when the detected page number is determined as not corresponding with the number of counted document images, said first determination section determines that the order of the document identified by the type identifier which contains the image identifier selected by said selection section does not correspond with the order of the document having been stored.

13. The image processing apparatus according to claim 9, wherein

the image identifier contains an identifier which indicates that the image is either a front side image or a back side image of one document sheet,

said judgment section judges whether two document images obtained from the front side and the back side of the one document sheet are respectively similar to reference images, and

when said judgment section judges that the two document images are respectively similar to reference images, said selection section selects image identifiers each of which identifies the reference image from among the image identifiers stored in said storage section, and wherein

said image processing apparatus further comprises:

a sixth determination section for, on the basis of the image identifier selected by said selection section, determining whether the two reference images are the front side image and the back side image of the one document sheet; and

a seventh determination section for, when the two reference images are determined as being the front side image and the back side image of the one document sheet, determining whether the reference image similar to the document image obtained from the front side of the one document sheet is the front side image and whether the reference image similar to the document image obtained from the back side of the one document sheet is the back side image;

wherein

when it is determined that the reference image similar to the document image obtained from the front side of the one document sheet is the back side image and that the reference image similar to the document image obtained from the back side of the one document sheet is the front side image, said first determination section determines that the order of the document identified by the type identifier which contains the image identifier selected by said selection section does not correspond with the order of the document having been stored.

14. The image processing apparatus according to claim 13, further comprising:

an exchange section for, when it is determined that the reference image similar to the document image obtained from the front side of the one document sheet is the back side image and that the reference image similar to the document image obtained from the back side of the one document sheet is the front side image, exchanging the front and back of the two document images.

15. The image processing apparatus according to claim 9, wherein

said storage section stores features as associated with an image identifier of the reference image, and wherein

said image processing apparatus further comprises

an extraction section for extracting features of the obtained document image, wherein

on the basis of the features extracted by said extraction section and the features of the reference image stored in said storage section, said judgment section judges whether the document image is similar to the reference image.

16. The image processing apparatus according to claim 9, further comprising

a notification section for notifying a situation when said first determination section determines that the order of the document identified by the type identifier which contains the image identifier selected by said selection section does not correspond with the order of the document having been stored.

17. An image reading apparatus comprising:

an image input apparatus for reading a document image; and

an image processing apparatus according to claim 9;

wherein

said image processing apparatus processes the document image read by said image input apparatus.

18. An image forming apparatus comprising:

an image processing apparatus according to claim 9; and

an image output apparatus for forming an output image on the basis of the document image processed by said image processing apparatus.

19. A computer-readable memory product which stores a computer program for causing a computer to judge whether an inputted document image is similar to a reference image stored in advance and then, on the basis of the judgment result, perform image processing on the document image, wherein

the computer program comprises steps of:

causing the computer to judge whether the inputted document image is similar to any one of a plurality of reference images;

when a document image is judged as being similar to a reference image, causing the computer to select an image identifier which identifies the reference image from among a plurality of image identifiers each for identifying a reference image; and

causing the computer, for each type identifier containing the selected image identifier, to determine whether the image identifier contained in the type identifier corresponds with the image identifier which identifies the reference image judged as being similar to the document image.