System and method of enabling a cellular/wireless device with imaging capabilities to decode printed alphanumeric characters

• US 20060098874A1
• Filed: 11/04/2005
• Published: 05/11/2006
• Est. Priority Date: 11/08/2004
• Status: Active Grant

• Current Assignee: DSPV Ltd.
• Original Assignee: DSPV Ltd.
• Inventors: Lev, Zvi Haim
• Granted Patent: US 7,447,362 B2
• Time in Patent Office: Days
• US Class Current: 382/182
• CPC Class Codes: G06V 20/62 Text, e.g. of license plates, overlay texts or captions on TV images
• CPC Class Codes: G06V 30/10 Character recognition
• CPC Class Codes: G06V 30/142 using hand-held instruments; Constructional details of the instruments
• CPC Class Codes: G06V 30/1478 of characters or characters lines
• CPC Class Codes: G06V 30/166 Normalisation of pattern dimensions

Abstract

A system and method for decoding printed alphanumeric characters from images or video sequences captured by a wireless device, including the pre-processing of the image or video sequence to optimize processing in all subsequent steps, the searching of one or more grayscale images for key alphanumeric characters on a range of scales, the comparing of the values on the range of scales to a plurality of templates in order to determine the characteristics of the alphanumeric characters, the performing of additional comparisons to a plurality of templates to determine character lines, line edges, and line orientation, the processing of information from prior operations to determine the corrected scale and orientation of each line, the recognizing of the identity of each alphanumeric characters in a string of such characters, and the decoding of the entire character string in digitized alphanumeric format.

Claims

1. A method for decoding printed alphanumeric characters from images or video sequences captured by a wireless device, the method comprising:

pre-processing the image or video sequence to optimize processing in all subsequent operations;

searching one or more grayscale images for key alphanumeric characters on a range of scales;

comparing the values on said range of scales to a plurality of templates in order to determine the characteristics of the alphanumeric characters;

performing additional comparisons to a plurality of templates to determine character lines, line edges, and line orientation;

processing information from prior said pre-processing, said searching, said comparing, and said performing additional comparisons, to determine the corrected scale and orientation of each line;

recognizing the identity of each alphanumeric character in a string of such characters;

decoding the entire character string in digitized alphanumeric format.

2. The method of claim 1, wherein:

the pre-processing comprises conversion from a color scale to a grayscale, and the stitching and combining of video frames to create a single larger and higher resolution grayscale image.

3. The method of claim 1, wherein:

the pre-processing comprises JPEG artifact removal to correct for compression artifacts of image/video compression executed by the wireless device.

4. The method of claim 1, wherein:

the pre-processing comprises part making of missing image/video data to correct for missing parts in the data due to transmission errors.

5. The method of claim 1, wherein:

comparing the key alphanumeric values to a plurality of template in order to determine the characteristics of the alphanumeric characters, comprises executing a modified Normalized Cross Correlation in which multiple parts are identified in the object to be captured from the image or video sequence, each part is compared against one or more templates, and all templates for all parts are cross-correlated to determine the characteristics of each alphanumeric image captured by the wireless device.

6. The method of claim 1, wherein:

the method is conducted in a single session of communication with the wireless communication device.

7. The method of claim 6, further comprising:

application logic processing of the decoded character string in digitized alphanumeric format in order to enable additional applications.

8. The method of claim 1, wherein:

the method is conducted in multiple sessions of communication with the wireless communication device.

9. The method of claim 8, further comprising:

application logic processing of the decoded character string in digitized alphanumeric format in order to enable additional applications.

10. A system for decoding printed alphanumeric characters from images or video sequences captured by a wireless device, the system comprising:

an object to be imaged or to be captured by video sequence, that contains within it alphanumeric characters;

a wireless portable device for capturing the image video sequence, and transmitting the captured image or video sequence to a data network;

a data network for receiving the image or video sequence transmitted by the wireless portable device, and for retransmitting it to a storage server;

a storage receiver for receiving the retransmitted image or video sequence, for storing the complete image or video sequence before processing, and for retransmitting the stored image or video sequence to a processing server;

a processing server for decoding the printed alphanumeric characters from the image or video sequence, and for transmitting the decoded characters to an additional server.

11. The system of claim 10 wherein:

the wireless portable device is any device that transmits and receives on any radio communication network, that has a means for photographically capturing an image or video sequence, and that is of sufficiently small dimensions and weight that it may be transported by an unaided human being.

12. The system of claim 10 wherein:

the wireless portable device is a wireless telephone with built-in camera capability.

13. The system of claim 10, wherein:

the wireless portable device comprises a digital imaging sensor, and a communication and image/video compression module.

14. The system of claim 10, wherein:

the additional server is a wireless messaging server for receiving the decoded characters transmitted by the processing server, and for retransmitting the decoded characters to a data network.

15. The system of claim 14, further comprising:

a content/information server for receiving the decoded characters from the processing server, for further processing the decoded characters by adding additional information as necessary, for retrieving content based on the decoded characters and the additional information, and for transmitting the processed decoded characters and additional information back to the processing server.

16. A processing server within a telecommunication system for decoding printed alphanumeric characters from images or video sequences captured by a wireless device, the processing server comprising:

a server for interacting with a plurality of storage servers, a plurality of content/information servers, and a plurality of wireless messaging servers, within the telecommunication system for decoding printed alphanumeric characters from images;

the server accessing image or video sequence data sent from a data network via a storage server, the server converting the image or video sequence data into a digital sequence of decoded alphanumeric characters, and the server communicating such digital sequence to an additional server.

17. The processing server of claim 16, wherein:

the additional server is a content/information server.

18. The processing server of claim 16, wherein:

the additional server is a wireless messaging server.

19. A computer program product, comprising a computer data signal in a carrier wave having computer readable code embodied therein for causing a computer to perform a method comprising:

pre-processing an alphanumeric image or video sequence;

searching on a range of scales for key alphanumeric characters in the image or sequence;

determining appropriate image scales;

searching for character lines, line edges, and line orientations;

correcting for the scale and orientation;

recognizing the strings of alphanumeric characters;

decoding the character strings.

20. The computer program product of claim 19, further comprising:

processing application logic in order to execute various applications on the decoded character string.