RECOGNITION OF NUMERICAL CHARACTERS IN DIGITAL IMAGES

• US 20140328541A1
• Filed: 06/11/2014
• Published: 11/06/2014
• Est. Priority Date: 08/30/2010
• Status: Active Grant

• Current Assignee: Alibaba Group Holding Ltd.
• Original Assignee: Alibaba Group Holding Ltd.
• Inventors: Sun, Xiang
• Granted Patent: US 8,958,643 B2
• Time in Patent Office: Days
• US Class Current: 382/181
• CPC Class Codes: G06V 30/10 Character recognition
• CPC Class Codes: G06V 30/18076 by analysing connectivity, e.g. edge linking, connected component analysis or slices
• CPC Class Codes: G06V 30/32 Digital ink

Abstract

Recognition of numerical characters is disclosed, including: extracting a subimage from a received image comprising information pertaining to a plurality of numerical characters, wherein the extracted subimage is associated with one of the plurality of numerical characters; and performing recognition based at least in part on a set of topological information associated with the subimage, including: processing the subimage to obtain the set of topological information associated with the subimage; comparing the set of topological information associated with the subimage with a preset set of stored topological information; determining that in the event that the set of topological information associated with the subimage matches the preset set of stored topological information, the subimage is associated with a recognized numerical character associated with the preset set of stored topological information.

Claims

1. A system, comprising:

a processor configured to;

extract a subimage from a received image comprising information pertaining to a plurality of numerical characters, wherein the extracted subimage is associated with one of the plurality of numerical characters;

perform recognition based at least in part on a set of topological information associated with the subimage, including;

process the subimage to obtain the set of topological information associated with the subimage, wherein the processing of the subimage includes;

obtain the set of topological information by extracting one or more vertices and one or more edges associated with the subimage;

determine whether a closed ring associated with at least a portion of the one or more vertices and at least a portion of the one or more edges exists; and

in the event that the closed ring exists, add a location of a point representing the closed ring to the set of topological information;

compare the set of topological information associated with the subimage with a preset set of stored topological information;

determine that in the event that the set of topological information associated with the subimage matches the preset set of stored topological information, the subimage is associated with a recognized numerical character associated with the preset set of stored topological information; and

a memory coupled to the processor and configured to provide the processor with instructions.

2. The system of claim 1, wherein the processor is further configured to refine the subimage.

3. The system of claim 2, wherein to refine the subimage includes to apply image degradation to the subimage.

4. The system of claim 1, wherein the preset set of stored topological information is stored in a database.

5. The system of claim 1, wherein the processor is further configured to display the recognized numerical character.

6. The system of claim 1, wherein the recognized numerical character is one of the following:

0, 1, 2, 3, 4, 5, 6, 7, 8, or 9.

7. A method, comprising:

extracting a subimage from a received image comprising information pertaining to a plurality of numerical characters, wherein the extracted subimage is associated with one of the plurality of numerical characters; and

performing recognition based at least in part on a set of topological information associated with the subimage, including;

processing the subimage to obtain the set of topological information associated with the subimage, wherein the processing of the subimage includes;

obtaining the set of topological information by extracting one or more vertices and one or more edges associated with the subimage;

determining whether a closed ring associated with at least a portion of the one or more vertices and at least a portion of the one or more edges exists; and

in the event that the closed ring exists, adding a location of a point representing the closed ring to the set of topological information;

comparing the set of topological information associated with the subimage with a preset set of stored topological information;

determining that in the event that the set of topological information associated with the subimage matches the preset set of stored topological information, the subimage is associated with a recognized numerical character associated with the preset set of stored topological information.

8. The method of claim 7, further comprising refining the subimage.

9. The method of claim 8, wherein refining the subimage includes applying image degradation to the subimage.

10. The method of claim 7, wherein the preset set of stored topological information is stored in a database.

11. The method of claim 7, further comprising displaying the recognized numerical character.

12. The method of claim 7, wherein the recognized numerical character is one of the following:

0, 1, 2, 3, 4, 5, 6, 7, 8, or 9.

13. A computer program product, the computer program product being embodied in a tangible non-transitory computer readable storage medium and comprising computer instructions for:

extracting a subimage from a received image comprising information pertaining to a plurality of numerical characters, wherein the extracted subimage is associated with one of the plurality of numerical characters; and

performing recognition based at least in part on a set of topological information associated with the subimage, including;

processing the subimage to obtain the set of topological information associated with the subimage, wherein the processing of the subimage includes;

obtaining the set of topological information by extracting one or more vertices and one or more edges associated with the subimage; and

determining whether a closed ring associated with at least a portion of the one or more vertices and at least a portion of the one or more edges exists;

in the event that the closed ring exists, adding a location of a point representing the closed ring to the set of topological information;

comparing the set of topological information associated with the subimage with a preset set of stored topological information;

determining that in the event that the set of topological information associated with the subimage matches the preset set of stored topological information, the subimage is associated with a recognized numerical character associated with the preset set of stored topological information.

14. The computer program product of claim 13, further comprising refining the subimage.

15. The computer program product of claim 14, wherein refining the subimage includes applying image degradation to the subimage.

16. The computer program product of claim 13, wherein the preset set of stored topological information is stored in a database.

17. The computer program product of claim 13, further comprising displaying the recognized numerical character.

18. The computer program product of claim 13, wherein the recognized numerical character is one of the following:

0, 1, 2, 3, 4, 5, 6, 7, 8, or 9.