System and method for monitoring a subject's eye

Patent metadata

Field	Value
Publication number	US-9636064-B2
Application number	US-201514859263-A
Country	US
Kind code	B2
Filing date	Sep 19, 2015
Priority date	Sep 19, 2014
Publication date	May 2, 2017
Grant date	May 2, 2017

Abstract

A system and a method for monitoring subject's eyes are disclosed. In one embodiment, spectral profiles of a frame substantially around a subject's eye are received from an image capturing device. Further, a state of the subject's eye in the frame is detected using the spectral profiles received from the image capturing device.

First claim

What is claimed is:

1. A camera system comprising:
an image capturing device configured to capture spectral profiles from a frame substantially around a subject's eye; and
an eye monitoring system communicatively connected to the image capturing device, wherein the eye monitoring system is configured to:
receive the spectral profiles of the frame from the image capturing device;
determine spectral profiles of an eye and skin including an eyelid in the received spectral profiles;
determine a number of the spectral profiles of the eye and a number of the spectral profiles of the skin including the eyelid;
determine a ratio of the number of the spectral profiles of the eye and the number of the spectral profiles of the skin including the eyelid; and
detect a state of the subject's eye in the frame using the determined ratio.

2. The system of claim 1 , wherein the eye monitoring system is configured to determine spectral profiles of at least one of a pupil, iris, or sclera in the received spectral profiles.

3. The system of claim 1 , wherein the eye monitoring system is configured to:
obtain spectral profiles of a reference frame substantially around the subject's eye;
compare the received spectral profiles of the frame with the spectral profiles of the reference frame; and
determine the spectral profiles of the eye and the skin including the eyelid in the received spectral profiles based on the comparison.

4. The system of claim 1 , wherein the eye monitoring system is configured to:
determine whether the ratio is greater than a predetermined threshold;
if so, detect the state of the subject's eye in the frame as an open state; and
if not, detect the state of the subject's eye in the frame as a closed state or a partially open state.

5. The system of claim 1 , wherein the eye monitoring system is configured to receive the spectral profiles of the frame from the image capturing device and to detect a state of the subject's eye in the frame using the received spectral profiles, for a number of subsequent frames substantially around the subject's eye to detect a state of the subject's eye in the number of subsequent frames.

6. The system of claim 5 , wherein the eye monitoring system is configured to generate an alert based on the state of the subject's eye in the frame and the number of subsequent frames.

7. The system of claim 5 , wherein the eye monitoring system is configured to:
determine whether the ratio of the number of the spectral profiles of the eye and the number of the spectral profiles of the skin including the eyelid is changing over the frame and the number of subsequent frames; and
detect a drowsiness state of the subject when the ratio is changing over the frame and the number of subsequent frames.

8. The system of claim 7 , wherein the eye monitoring system is configured to generate an alert upon detecting the drowsiness state of the subject.

9. The system of claim 7 , wherein the eye monitoring system is configured to detect the drowsiness state of the subject when the ratio is decreasing over the frame and the number of subsequent frames.

10. The system of claim 7 , wherein the eye monitoring system is configured to:
detect gradual drowsiness of the subject when the ratio changes gradually over the frame and the number of subsequent frames; and
detect persistent drowsiness of the subject when the ratio changes significantly over the frame and the number of subsequent frames.

11. A method for monitoring a subject's eye, comprising:
receiving spectral profiles of a frame substantially around a subject's eye from an image capturing device;
determining spectral profiles of an eye and skin including an eyelid in the received spectral profiles;
determining a number of the spectral profiles of the eye and a number of the spectral profiles of the skin including the eyelid;
determining a ratio of the number of the spectral profiles of the eye and the number of the spectral profiles of the skin including the eyelid; and
detecting a state of the subject's eye in the frame based on the determined ratio.

12. The method of claim 11 , further comprising comparing the received spectral profiles of the frame with spectral profiles of a reference frame substantially around the subject's eye, and wherein determining the spectral profiles of the eye and the skin including the eyelid in the received spectral profiles is based on the comparison.

13. The method of claim 11 , further comprising:
receiving spectral profiles of a number of subsequent frames substantially around the subject's eye; and
detecting a state of the subject's eye in the number of subsequent frames.

14. The method of claim 13 , further comprising:
determining whether the ratio of the number of the spectral profiles of the eye and the number of the spectral profiles of the skin including the eyelid is changing over the frame and the number of subsequent frames; and
detecting a drowsiness state of the subject when the ratio is changing over the frame and the number of subsequent frames.

15. The method of claim 14 , further comprising generating an alert upon detecting the drowsiness state of the subject.

16. A non-transitory computer-readable storage medium comprising instructions for monitoring a subject's eye, the instructions executable by a computing device to:
receive spectral profiles of a frame substantially around a subject's eye from an image capturing device;
determine spectral profiles of an eye and skin including an eyelid in the received spectral profiles;
determine a number of the spectral profiles of the eye and a number of the spectral profiles of the skin including the eyelid;
determine a ratio of the number of the spectral profiles of the eye and the number of the spectral profiles of the skin including the eyelid; and
detect a state of the subject's eye in the frame based on the determined ratio.

17. The non-transitory computer-readable storage medium of claim 16 , further comprising instructions executable by a computing device to compare the received spectral profiles of the frame with spectral profiles of a reference frame substantially around the subject's eye, and wherein determining the spectral profiles of the eye and the skin including the eyelid in the received spectral profiles is based on the comparison.

18. The non-transitory computer-readable storage medium of claim 16 , further comprising instructions executable by a computing device to:
receive spectral profiles of a number of subsequent frames substantially around the subject's eye; and
detect a state of the subject's eye in the number of subsequent frames.

19. The non-transitory computer-readable storage medium of claim 18 , further comprising instructions executable by a computing device to:
determine whether the ratio of the number of the spectral profiles of the eye and the number of the spectral profiles of the skin including the eyelid is changing over the frame and the number of subsequent frames; and
detect a drowsiness state of the subject when the ratio is changing over the frame and the number of subsequent frames.

20. The non-transitory computer-readable storage medium of claim 19 , further comprising instructions executable by a computing device to generate an alert upon detecting the drowsiness state of the subject.

Assignees

• Imec India Private Ltd
• Imec Vzw

Inventors

• Perugupalli Prasanth
• Kumar Nath Sumit

Classifications

• G06V10/60

  relating to illumination properties, e.g. using a reflectance or lighting model · CPC title

• B60W2050/143

  Alarm means · CPC title

• A61B3/14

  Arrangements specially adapted for eye photography · CPC title

• B60W2040/0827

  due to sleepiness · CPC title

• A61B5/18 Primary

  for vehicle drivers {or machine operators} · CPC title