System and method of detecting eye closure based on edge lines

• US 7,253,738 B2
• Filed: 03/10/2005
• Issued: 08/07/2007
• Est. Priority Date: 03/10/2005
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Delphi Technologies, Inc. (BorgWarner Incorporated)
• Inventors: Hammoud, Riad I., Malawey, Phillip V.
• Primary Examiner(s): NGUYEN, PHUNG
• Application Number:
  US11/077,041
• Publication Number:
  US 20060204041A1
• Time in Patent Office: 880 Days
• Field of Search: 340/575, 340/573.1, 340/573, 382/107, 382/117, 348/77, 348/78, 180/272
• US Class Current: 340/575
• CPC Class Codes: G06V 40/18 Eye characteristics, e.g. of the iris
• CPC Class Codes: G08B 21/06 indicating a condition of sleep, e.g. anti-dozing alarms

Abstract

A system and method are provided for monitoring an eye to determine eye closure. The system includes a video imaging camera oriented to generate images of an eye, and a video processor for processing the images. The processor includes an edge detector for detecting edges of the eye in the image, and a line selector for generating a plurality of lines at multiple angles representative of the detected edges. The processor determines the state of eye closure, such as eye open or eye closed, based on the number of lines at selected angles. The system may be employed on a vehicle to determine the eye closure of a driver of the vehicle.

Claims

1. A system for monitoring an eye and determining eye closure, said system comprising:

a video imaging camera oriented to generate images of an eye; and

a video processor for processing the images generated with the video imaging camera, said video processor comprising an edge detector for detecting edges of the eye in the image and a line selector for selecting a plurality of lines representative of the detected edges at multiple selected angles, said processor determining a state of eye closure based on the number of said lines at selected angles.

2. The system as defined in claim 1, wherein said plurality of lines are substantially linear.

3. The system as defined in claim 1, wherein said processor determines the state of eye closure based on the number of said lines at each of a plurality of the selected angles.

4. The system as defined in claim 1, wherein said processor further determines the number of lines at each of a plurality of selected angles, and determines a state of eye closure based on the number of said lines at each of the plurality of selected angles.

5. The system as defined in claim 1, wherein said processor performs a Hough Transformation to transform the plurality of lines from Cartesian coordinates to polar space and further determines the number of lines at each of the multiple selected angles.

6. The system as defined in claim 1, wherein said detected edges comprise a gray-scale representation of pixels imaging the eye.

7. The system as defined in claim 1, wherein the system is employed in a vehicle for monitoring an eye of a driver of the vehicle.

8. A vehicle eye monitoring system for monitoring an eye of a person in a vehicle and determining eye closure, said system comprising:

a video imaging camera located on a vehicle and oriented to generate images of an eye of a person in the vehicle; and

a video processor for processing the images generated with the video imaging camera, said video processor comprising an edge detector for detecting edges of the eye in the image and a line selector for selecting a plurality of lines representative of the detected edges at multiple angles, said processor determining a state of eye closure based on the number of said lines at selected angles.

9. The system as defined in claim 8, wherein said plurality of lines are substantially linear.

10. The system as defined in claim 8, wherein said processor determines the state of eye closure based on the number of said lines at each of a plurality of the selected angles.

11. The system as defined in claim 8, wherein said processor further determines the number of lines at each of a plurality of selected angles, and determines a state of eye closure based on the number of said lines at each of the plurality of selected angles.

12. The system as defined in claim 8, wherein said line selector comprises a Hough Transformation for transforming the plurality of lines from Cartesian coordinates to polar space and further determines the number of lines at each of the multiple selected angles.

13. The system as defined in claim 8, wherein said detected edges comprise a gray-scale representation of pixels imaging the eye.

14. A method of monitoring an eye and determining eye closure, said method comprising the steps of:

arranging a video imaging camera to generate images of an eye;

generating an image of the eye;

processing the image to identify edges of the eye in the image;

generating a plurality of lines representative of the edges at multiple selected angles; and

determining an eye closure state based on the number of said lines at selected angles.

15. The method as defined in claim 14, wherein the step of generating a plurality of lines comprises generating a plurality of lines that are substantially linear.

16. The method as defined in claim 14, wherein the step of determine an eye closure state comprises determining the eye closure state based on the number of said lines at each of a plurality of the selected angles.

17. The method as defined in claim 14 further comprising the step of generating the number of lines at each of the multiple selected angles and determining an eye closure state based on the number of lines at each of the plurality of selected angles.

18. The method as defined in claim 14, wherein the step of generating a plurality of lines comprises transforming said plurality of lines from Cartesian coordinates to polar space with a Hough Transformation and determining the number of lines at each of the multiple selected angles.

19. The method as defined in claim 14, wherein said step of arranging a video imaging camera comprises arranging the video imaging camera in a vehicle to monitor the eye of the driver of the vehicle.