METHOD AND APPARATUS FOR DETECTING TARGET OBJECT IN BLIND AREA OF VEHICLE

• US 20150339533A1
• Filed: 03/02/2015
• Published: 11/26/2015
• Est. Priority Date: 05/22/2014
• Status: Active Grant

• Current Assignee: Neusoft Reach Automotive Technology (Shanghai) Co., Ltd.
• Original Assignee: Neusoft Corporation
• Inventors: LIU, Wei, Yuan, Huai, Duan, Chengwei
• Granted Patent: US 9,904,856 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06F 18/22 Matching criteria, e.g. proximity measures
• CPC Class Codes: G06T 2207/10016 Video; Image sequence
• CPC Class Codes: G06T 2207/30261 Obstacle
• CPC Class Codes: G06T 7/74 involving reference images or patches
• 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

Abstract

A method for detecting a target object in a blind area of a vehicle is provided by embodiments of the application. The method includes: acquiring at least one frame of an image generated by shooting a blind area of a vehicle by a shooting device; extracting an image feature of an area where at least one predetermined detection gate is located in the image; and matching the image feature of the area where the predetermined detection gate is located with a matching template of the predetermined detection gate to determine a target object. An apparatus for detecting a target object in a blind area of a vehicle is further provided by embodiments of the application.

Claims

1. A method for detecting a target object in a blind area of a vehicle, comprising:

acquiring at least one frame of an image generated by shooting a blind area of a vehicle by a shooting device;

extracting an image feature of an area where at least one predetermined detection gate is located in the image; and

matching the image feature of the area where the predetermined detection gate is located with a matching template of the predetermined detection gate, to determine a target object.

2. The method according to claim 1, wherein the area where the predetermined detection gate is located comprises a complete image of the target object.

3. The method according to claim 2, wherein the area where the predetermined detection gate is located comprising the complete image of the target object comprises:

the range of the target object corresponding to the detection gate in the blind area of the vehicle meeting a requirement of;

an arctangent value of a ratio of a depth distance to a lateral distance from the target object included in the detection gate to the vehicle being equal to or less than a horizontal view angle of the shooting device, wherein the depth distance is a vertical distance from the shooting device arranged on the vehicle to a front plane of the target object, and the lateral distance is a vertical distance from a depth axis of the shooting device arranged on the vehicle to a left plane or a right plane of the target object.

4. The method according to claim 3, wherein in a case that the shooting device arranged on the vehicle is a plane camera, the arctangent value of the ratio of the depth distance to the lateral distance from the target object included in the detection gate to the vehicle being equal to or less than the horizontal view angle of the shooting device is met by meeting a requirement of:

the depth distance from the target object included in the detection gate to the vehicle being equal to or larger than

5. The method according to claim 4, wherein in a case that a pixel coordinate of a lower left corner of the detection gate comprising the complete image of the target object in the plane image is (u, v), a pixel height of the detection gate is H, a pixel width of the detection gate is W, the depth distance of the target object included in the detection gate is VerD, the lateral distance of the target object included in the detection gate is HonD, an actual height of the target object is Obj_—

3DH, and an actual width of the target object is Obj_—

3DW, the detection gate is determined by the following equations;

u=Foot_col−

Obj_pixW

v=Foot_row

W=Obj_pixW

H=Obj_pixH

wherein Foot_row is a row in the plane image corresponding to a lower edge of the front plane of the target object, which is determined by the following equation;

6. The method according to claim 3, wherein in a case that the shooting device arranged on the vehicle is a fisheye camera, a height of the fisheye camera is Cam_H, a Euclidean distance from the target object to the fisheye camera is D, a depth distance from the target object to the fisheye camera is VerD, a lateral distance from the target object to the fisheye camera is HonD, an actual height of the target object is Obj_—

3DH, an actual width of the target object is Obj_—

3DW, a parameter of a cylinder image converted from a fisheye image is ay, a pixel coordinate of a center of the cylinder image is (u0, v0), a pixel width of the fisheye image is imgW, a pixel height of the fisheye image is imgH, a pixel coordinate of a lower left corner of the detection gate comprising the complete image of the target object in the cylinder image is (u, v), a pixel height of the detection gate is H, and a pixel width of the detection gate is W, the detection gate is determined by the following equations;

u=Foot_col−

Obj_pixW

v=Foot_row

W=Obj_pixW

H=Obj_pixH

wherein Foot_row is a row in the cylinder image corresponding to a lower edge of the front plane of the target object, which is determined by the following equation;

7. The method according to claim 1, wherein the number of the at least one predetermined detection gate is 2n×

m, wherein n is the number of the detection gates corresponding to the target objects which have same lateral distances and different depth distances on one side of the vehicle, and m is the number of the detection gates corresponding to the target objects which have same depth distances and different lateral distances on one side of the vehicle, wherein n and m are natural numbers larger than or equal to 1.

8. The method according to claim 2, wherein the number of the at least one predetermined detection gate is 2n×

m, wherein n is the number of the detection gates corresponding to the target objects which have same lateral distances and different depth distances on one side of the vehicle, and m is the number of the detection gates corresponding to the target objects which have same depth distances and different lateral distances on one side of the vehicle, wherein n and m are natural numbers larger than or equal to 1.

9. The method according to claim 3, wherein the number of the at least one predetermined detection gate is 2n×

m, wherein n is the number of the detection gates corresponding to the target objects which have same lateral distances and different depth distances on one side of the vehicle, and m is the number of the detection gates corresponding to the target objects which have same depth distances and different lateral distances on one side of the vehicle, wherein n and m are natural numbers larger than or equal to 1.

10. The method according to claim 4, wherein the number of the at least one predetermined detection gate is 2n×

m, wherein n is the number of the detection gates corresponding to the target objects which have same lateral distances and different depth distances on one side of the vehicle, and m is the number of the detection gates corresponding to the target objects which have same depth distances and different lateral distances on one side of the vehicle, wherein n and m are natural numbers larger than or equal to 1.

11. The method according to claim 5, wherein the number of the at least one predetermined detection gate is 2n×

m, wherein n is the number of the detection gates corresponding to the target objects which have same lateral distances and different depth distances on one side of the vehicle, and m is the number of the detection gates corresponding to the target objects which have same depth distances and different lateral distances on one side of the vehicle, wherein n and m are natural numbers larger than or equal to 1.

12. The method according to claim 6, wherein the number of the at least one predetermined detection gate is 2n×

m, wherein n is the number of the detection gates corresponding to the target objects which have same lateral distances and different depth distances on one side of the vehicle, and m is the number of the detection gates corresponding to the target objects which have same depth distances and different lateral distances on one side of the vehicle, wherein n and m are natural numbers larger than or equal to 1.

13. The method according to claim 7, wherein differences between the lateral distances of the target objects having the same depth distances and a lane width fit normal distribution.

14. The method according to claim 7, wherein

matching templates of the detection gates corresponding to the target objects which have the same depth distances are the same, or

matching the image feature of the area where the predetermined detection gate is located with the matching template of the predetermined detection gate to determine the target object comprises:

matching the image feature of the area where the predetermined detection gate is located with the matching template of the predetermined detection gate;

determining a matching degree between the matching template of the predetermined detection gate and the image feature of the area where the predetermined detection gate is located;

judging whether the matching degree is larger than a predetermined judging threshold; and

determining that the target object corresponding to the detection gate exists if the matching degree is larger than the predetermined judging threshold.

15. An apparatus for detecting a target object in a blind area of a vehicle, comprising an image acquiring unit, a feature extracting unit and an object matching unit, wherein

the image acquiring unit is configured to acquire at least one frame of an image generated by shooting a blind area of a vehicle by a shooting device;

the feature extracting unit is configured to extract an image feature of an area where at least one predetermined detection gate is located in the image; and

the object matching unit is configured to match the image feature with a matching template of the detection gate, to determine a target object.

16. The apparatus according to claim 15, wherein the area where the predetermined detection gate is located comprises a complete image of the target object.

17. The apparatus according to claim 16, wherein the area where the predetermined detection gate is located comprising the complete image of the target object comprises:

the range of the target object corresponding to the detection gate in the blind area of the vehicle meeting a requirement of;

an arctangent value of a ratio of a depth distance to a lateral distance from the target object included in the detection gate to the vehicle being equal to or less than a horizontal view angle of the shooting device, wherein the depth distance is a vertical distance from the shooting device arranged on the vehicle to a front plane of the target object, and the lateral distance is a vertical distance from a depth axis of the shooting device arranged on the vehicle to a left plane or a right plane of the target object.

18. The apparatus according to claim 17, wherein in a case that the shooting device arranged on the vehicle is a plane camera, the arctangent value of the ratio of the depth distance to the lateral distance from the target object included in the detection gate to the vehicle being equal to or less than the horizontal view angle of the shooting device is met by meeting a requirement of:

the depth distance from the target object included in the detection gate to the vehicle being equal to or larger than

19. The apparatus according to claim 18, wherein in a case that a pixel coordinate of a lower left corner of the detection gate comprising the complete image of the target object in the plane image is (u, v), a pixel height of the detection gate is H, a pixel width of the detection gate is W, the depth distance of the target object included in the detection gate is VerD, the lateral distance of the target object included in the detection gate is HonD, an actual height of the target object is Obj_—

3DH, and an actual width of the target object is Obj_—

3DW, the detection gate is determined by the following equations;

u=Foot_col−

Obj_pixW

v=Foot_row

W=Obj_pixW

H=Obj_pixH

wherein Foot_row is a row in the plane image corresponding to a lower edge of the front plane of the target object, which is determined by the following equation;

20. The apparatus according to claim 17, wherein in a case that the shooting device arranged on the vehicle is a fisheye camera, a height of the fisheye camera is Cam_H, a Euclidean distance from the target object to the fisheye camera is D, a depth distance from the target object to the fisheye camera is VerD, a lateral distance from the target object to the fisheye camera is HonD, an actual height of the target object is Obj_—

3DH, an actual width of the target object is Obj_—

3DW, a parameter of a cylinder image converted from a fisheye image is ay, a pixel coordinate of a center of the cylinder image is (u0, v0), a pixel width of the fisheye image is imgW, a pixel height of the fisheye image is imgH, a pixel coordinate of a lower left corner of the detection gate comprising the complete image of the target object in the cylinder image is (u, v), a pixel height of the detection gate is H, and a pixel width of the detection gate is W, the detection gate is determined by the following equations;

u=Foot_col−

Obj_pixW

v=Foot_row

W=Obj_pixW

H=Obj_pixH

wherein Foot_row is a row in the cylinder image corresponding to a lower edge of the front plane of the target object, which is determined by the following equation;