Road region detection

Patent metadata

Field	Value
Publication number	US-10936883-B2
Application number	US-201314770087-A
Country	US
Kind code	B2
Filing date	Mar 1, 2013
Priority date	Mar 1, 2013
Publication date	Mar 2, 2021
Grant date	Mar 2, 2021

Abstract

A road region detection method is provided. The method includes: obtaining a first image captured by a camera at a first time point and a second image captured by the camera at a second time point (S101), converting the first and second images into a first top view and a second top view, respectively (S103), obtaining a movement vector matrix which substantially represents movement of a road region relative to the camera between the first and second time points (S105), and determining whether a candidate point belongs to the road region by determining whether a position change of the candidate point between the first and second top views conforms to the movement vector matrix. The accuracy and efficiency may be improved.

First claim

We claim:

1. A method for detecting road regions, comprising:
obtaining a first image captured by a camera at a first time point and a second image captured by the camera at a second time point;
converting the first image and the second image into a first top view and a second top view, respectively;
obtaining a movement vector matrix which substantially represents movement of a road region relative to the camera between the first time point and the second time point; and
determining whether a candidate point belongs to the road region by determining whether a position change of the candidate point between the first top view and the second top view conforms to the movement vector matrix.

2. The method according to claim 1 , wherein a scale of the first top view and the second top view is substantially similar to a real-world scale.

3. The method according to claim 1 , wherein the movement vector matrix is obtained by:
obtaining a rotation matrix R 1 and a translation matrix T 1 which substantially represent movement of the camera between the first time point and the second time point; and
obtaining the movement vector matrix, comprising a rotation matrix R 2 and a translation matrix T 2 , based on R 1 , T 1 , and one or more extrinsic parameters of the camera.

4. The method according to claim 3 , wherein, if the camera's pitch angle α equals to zero, then R 2 equals −R 1 , and T 2 equals −T 1 .

5. The method according to claim 3 , wherein, if the camera's pitch angle α does not equal to zero, then R 2 equals −R 1 , and T 2 equals

-

(

cos
⁢

⁢
α

0

0

0

1

0

0

0

sin
⁢

⁢
α

)

*

T
1

.

6. The method according to claim 1 , wherein the movement vector matrix is obtained by:
Identifying a group of feature points on the first top view;
tracking the feature points on the second top view; and
calculating R 2 and T 2 by solving an objective function:

arg
⁢

⁢
min

R
2

,

T
2

⁢

∑

{

I
2

⁡

(

X

T
⁢

⁢
2

,

Y

T
⁢

⁢
2

)

-

I
1

⁡

[

f
⁡

(

X

T
⁢

⁢
1

,

Y

T
⁢

⁢
1

)

]

}

2

,

where argmin defines a group of feature points of an argument for which the function Σ{I 2 (X T2 ,Y T2 )−I 1 [f(X T1 ,Y T1 )]} 2 attains a minimum value,
where I 2 (X T2 ,Y T2 ) defines a set of coordinates indicating the position of a feature point on the second top view,
where I 1 [f(X T1 ,Y T1 )] defines a set of coordinates calculated based on:

Assignees

• Harman Int Ind
• Zheng Wenming
• Zhu Haitian
• Ruan Zongcai
• Zhang Yankun

Inventors

• Zheng Wenming
• Zhu Haitian
• Ruan Zongcai
• Zhang Yankun

Classifications

• G06V20/588

  Recognition of the road, e.g. of lane markings; Recognition of the vehicle driving pattern in relation to the road · CPC title

• G06V20/56 Primary

  exterior to a vehicle by using sensors mounted on the vehicle · CPC title

• G06T7/215

  Motion-based segmentation · CPC title

• G06T2207/30244

  Camera pose · CPC title

• G06T2207/30256

  Lane; Road marking · CPC title