FORWARD COLLISION WARNING TRAP AND PEDESTRIAN ADVANCED WARNING SYSTEM

• US 20120140076A1
• Filed: 12/07/2011
• Published: 06/07/2012
• Est. Priority Date: 12/07/2010
• Status: Active Grant

• Current Assignee: MobilEye Vision Technologies Ltd. (Intel Corporation)
• Original Assignee: MobilEye Vision Technologies Ltd. (Intel Corporation)
• Inventors: Gurman, Amiad, Stein, Gideon, ROSENBAUM, Dan
• Granted Patent: US 9,251,708 B2
• Time in Patent Office: Days
• US Class Current: 348/148
• CPC Class Codes: G06T 2207/10016 Video; Image sequence
• CPC Class Codes: G06T 2207/30261 Obstacle
• CPC Class Codes: G06T 7/246 using feature-based methods, e.g. the tracking of corners or segments
• CPC Class Codes: G06V 20/58 Recognition of moving objects or obstacles, e.g. vehicles or pedestrians; Recognition of traffic objects, e.g. traffic signs, traffic lights or roads
• CPC Class Codes: G08G 1/165 for passive traffic, e.g. including static obstacles, trees
• CPC Class Codes: G08G 1/166 for active traffic, e.g. moving vehicles, pedestrians, bikes

Abstract

A method for providing a forward collision warning using a camera mountable in a motor vehicle. The method acquires multiple image frames at known time intervals. A patch may be selected in at least one of the image frames. Optical flow may be tracked between the image frames of multiple image points of the patch. Based on the fit of the image points to a model, a time-to collision (TTC) may be determined if a collision is expected. The image points may be fit to a road surface model and a portion of the image points is modeled to be imaged from a road surface. A collision is not expected based on the fir of the image points to the road surface model.

Claims

1. A method for providing a forward collision warning using a camera mountable in a motor vehicle, the method comprising:

acquiring a plurality of image frames at known time intervals;

selecting a patch in at least one of the image frames;

tracking optical flow between the image frames of a plurality of image points of said patch;

fitting the image points to at least one model; and

based on the fit of the image points to said at least one model, determining a time-to-collision (TTC) if a collision is expected.

2. The method of claim 1, further comprising:

fitting the image points to a road surface model, wherein at least a portion of the image points is modeled to be imaged from a road surface;

determining a collision is not expected based on the fit of the image points to the model.

3. The method of claim 1, further comprising:

fitting the image points to a vertical surface model, wherein at least a portion of the image points is modeled to be imaged from a vertical object; and

determining the TTC based on the fit of the image points to the vertical surface model.

4. The method of claim 3, further comprising:

detecting in the image frames a candidate image of a pedestrian wherein said patch is selected to include the candidate image of the pedestrian; and

verifying the candidate image as an image of an upright pedestrian and not an object in the road surface when the best fit model is the vertical surface model.

5. The method of claim 3, further comprising:

detecting in the image frames a vertical line, wherein said patch is selected to include said vertical line;

verifying the vertical line as an image of a vertical object and not of an object in the road surface when the best fit model is the vertical surface model.

6. The method of claim 1, wherein said at least one model also includes a mixed model wherein a first portion of the image points is modeled to be imaged from a road surface and a second portion of the image points is modeled to be imaged from a substantially vertical object.

7. The method of claim of claim 1, further comprising:

issuing a warning based on said time-to-collision being less than a threshold.

8. A system including a camera and a processor mountable in a motor vehicle, the system operable to provide a forward collision warning, the system operable to:

acquire a plurality of image frames at known time intervals;

select a patch in at least one of the image frames;

track optical flow between the image frames of a plurality of image points of said patch;

fit the image points to at least one model; and

based on the fit of the image points to the at least one model, determine a time-to-collision (TTC) if a collision is expected.

9. The system of claim 8, further operable to:

fit the image points to a road surface model;

determine a collision is not expected based on the fit of the image points to the road surface model.

10. A method of providing a forward collision warning using a camera and a processor mountable in a motor vehicle, the method comprising:

acquiring a plurality of image frames at known time intervals;

selecting a patch in an image frame corresponding to where the motor vehicle will be in a predetermined time interval; and

monitoring said patch, if an object is imaged in said patch then issuing a forward collision warning.

11. The method of claim of claim 10, further comprising:

determining if said object includes a substantially vertical portion.

12. The method of claim 11, wherein said determining is performed by:

tracking optical flow between the image frames of a plurality of image points of said patch; and

fitting the image points to at least one model.

13. The method of claim 11, wherein at least a portion of the image points is modeled to be imaged from a vertical object;

and

based on the fit of the image points to said at least one model, determining a time-to-collision (TTC), if a collision is expected

14. The method of claim 11, wherein said at least one model includes a road surface model, the method further comprising:

fitting the image points to a road surface model;

determining a collision is not expected based on the fit of the image points to the road surface model.

15. The method of claim 11, further comprising:

said issuing said warning when the best fit model is a vertical surface model.

16. A system for providing a forward collision warning in a motor vehicle, the system comprising:

a camera mountable in the motor vehicle, said camera operable to acquire a plurality of image frames at known time intervals;

a processor operable to;

select a patch in an image frame corresponding to where the motor vehicle will be in a predetermined time interval;

to monitor said patch; and

if an object is imaged in said patch, then issue a forward collision warning.

17. The system of claim 16, wherein the processor is further operable to determine if said object includes a substantially vertical portion by

tracking optical flow between the image frames of a plurality of image points of the object in the patch;

fitting the image points to at least one model; and

based on the fit of the image points to said at least one model, to determine a time to collision (TTC) if a collision is expected.

18. The system of claim 16, wherein the processor is operable to issue a forward collision warning based on TTC being less than a threshold.