Method and apparatus for performing optical character recognition (OCR) and text stitching

• US 20030169923A1
• Filed: 03/07/2002
• Published: 09/11/2003
• Est. Priority Date: 03/07/2002
• Status: Active Grant

• Current Assignee: Marvell International Technology, Ltd. (Marvell Technology Group Limited)
• Original Assignee: Marvell International Technology, Ltd. (Marvell Technology Group Limited)
• Inventors: Butterworth, Mark Melvin
• Granted Patent: US 7,343,049 B2
• Time in Patent Office: Days
• US Class Current: 382/181
• CPC Class Codes: G06V 10/10 Image acquisition document image scanning and transmission H04N1/00; control of digital cameras H04N23/60
• CPC Class Codes: G06V 10/16 using multiple overlapping images; Image stitching

Abstract

A method of generating an electronic text file from a paper-based document that includes a plurality of characters includes capturing a plurality of partially overlapping digital images of the document. Optical character recognition is performed on each one of the plurality of captured digital images, thereby generating a corresponding plurality of electronic text files. Each one of the electronic text files includes a portion of the plurality of characters in the document. The plurality of electronic text files are compared with one another to identify characters that are in common between the electronic text files. The plurality of electronic text files are combined into a combined text file based on the comparison. The combined text file includes the plurality of characters in the document.

Claims

1. A method of generating an electronic text file from a paper-based document that includes a plurality of characters, the method comprising:

capturing a plurality of partially overlapping digital images of the document;

performing optical character recognition on each one of the plurality of captured digital images, and thereby generating a corresponding plurality of electronic text files, each one of the electronic text files including a portion of the plurality of characters in the document;

comparing the plurality of electronic text files with one another to identify characters that are in common between the electronic text files; and

combining the plurality of electronic text files into a combined text file based on the comparison, wherein the combined text file includes the plurality of characters in the document.

2. The method of claim 1, and further comprising:

storing order information representing the order in which the plurality of digital images were captured.

3. The method of claim 2, wherein the comparison of the plurality of text files is based on the stored order information.

4. The method of claim 1, wherein the plurality of digital images are captured with a digital camera, the method further comprising:

providing direction information indicative of the direction of movement of the digital camera during the capture of the plurality of digital images.

5. The method of claim 1, wherein the plurality of digital images are captured with a digital camera, the method further comprising:

automatically detecting direction information indicative of the direction of movement of the digital camera during the capture of the plurality of digital images.

6. The method of claim 1, wherein the plurality of digital images are captured automatically at a predefined time interval.

7. A digital camera comprising:

a lens;

an image sensor for generating a plurality of partially overlapping digital images based on optical images directed onto the image sensor by the lens, and

a controller coupled to the image sensor and configured to perform optical character recognition on the plurality of digital images, and thereby generate an electronic text file for each one of the plurality of digital images, the electronic text file for each digital image including text appearing in the digital image, the controller configured to identify overlapping text between electronic text files and stitch the text in the plurality of text files together based on the identified overlapping text.

8. The digital camera of claim 7, and further comprising:

a memory for storing order information representing the order in which the plurality of digital images were captured.

9. The digital camera of claim 7, and further comprising:

an input device for inputting direction information indicative of the direction of movement of the digital camera while the plurality of digital images are being captured.

10. The digital camera of claim 7, and further comprising:

a motion detector for automatically detecting direction information indicative of the direction of movement of the digital camera during the capture of the plurality of digital images.

11. The digital camera of claim 7, wherein the controller is configured to cause the plurality of digital images to be captured automatically at a predefined time interval.

12. An electronic device including a digital camera, the electronic device comprising:

a display screen for displaying images captured with the digital camera;

an input device for inputting information into the electronic device; and

a processor configured to perform optical character recognition on digital images captured with the digital camera and generate corresponding electronic text files, the electronic text file for each digital image including text appearing in the digital image, the controller configured to stitch the text from the electronic text files together.

13. The electronic device of claim 12, wherein the electronic device is one of a cellular telephone, a personal digital assistant device, and a laptop computer.

14. The electronic device of claim 12, and further comprising:

a memory for storing order information representing the order in which the digital images were captured.

15. The electronic device of claim 12, wherein the device is configured to allow a user to enter direction information via the input device, the direction information indicative of the direction of movement of the digital camera while the digital images are being captured.

16. The electronic device of claim 12, and further comprising:

a motion detector for automatically detecting direction information indicative of the direction of movement of the digital camera during the capture of the digital images.

17. The electronic device of claim 12, wherein the processor is configured to cause the digital images to be captured automatically at a predefined time interval.