Apparatus and Method for Detecting Posture of Camera Mounted on Vehicle

• US 20120314073A1
• Filed: 06/06/2012
• Published: 12/13/2012
• Est. Priority Date: 06/13/2011
• Status: Active Grant

• Current Assignee: Alpine Electronics Incorporated (Alps Alpine Co., Ltd.)
• Original Assignee: Alpine Electronics Incorporated (Alps Alpine Co., Ltd.)
• Inventors: Shimoda, Kenichi, Watanabe, Hisayuki, Hiruta, Kazuhiro
• Granted Patent: US 9,361,687 B2
• Time in Patent Office: Days
• US Class Current: 348/148
• CPC Class Codes: G06T 2207/30204 Marker
• CPC Class Codes: G06T 2207/30244 Camera pose
• CPC Class Codes: G06T 2207/30252 Vehicle exterior; Vicinity of vehicle
• CPC Class Codes: G06T 7/80 Analysis of captured images to determine intrinsic or extrinsic camera parameters, i.e. camera calibration

Abstract

An in-vehicle camera posture detecting apparatus includes a first image storing unit configured to store an image of a calibration sheet placed near the vehicle, the calibration sheet having a plurality of calibration marks, a first posture estimating unit for estimating the posture of the camera based on the first image, a second image storing unit that stores an image of the calibration sheet after movement of the vehicle, a second posture estimating unit that estimates the posture of the camera based on the second image, a sheet deviation calculating unit that calculates an amount of deviation of the calibration sheet from a predetermined position based on the estimates provided by the first and second posture estimating units, and a camera posture determining unit that determines the posture of the camera based on a posture estimated value and the calculated amount of deviation.

Claims

1. An in-vehicle camera posture detecting apparatus for detecting a positional alignment of a camera mounted on a vehicle, the apparatus comprising:

a first image storing unit configured to store, as a first image, an image of a calibration sheet placed near the vehicle and captured by the camera, the calibration sheet having a plurality of calibration marks thereon;

a first posture estimating unit configured to estimate the posture of the camera based on the first image;

a second image storing unit configured to store, as a second image, an image of the calibration sheet captured by the camera after movement of the vehicle by a predetermined distance;

a second posture estimating unit configured to estimate the posture of the camera based on the second image;

a sheet deviation calculating unit configured to calculate an amount of deviation of the calibration sheet from a predetermined position based on the estimates provided by the first and second posture estimating units; and

a camera posture determining unit configured to determine the posture of the camera based on a posture estimated value obtained by at least one of the first and second posture estimating units and the calculated amount of deviation.

2. The apparatus according to claim 1, wherein the predetermined distance by which the vehicle is moved is calculated based on the posture estimated values obtained by the first and second posture estimating units.

3. The apparatus according to claim 1, wherein the camera is installed in a default position and the sheet deviation calculating unit is configured to calculate the deviation amount based on the relationship between the default position of the camera, the estimations by the first and second posture estimating units, and the deviation amount of the calibration sheet from the predetermined position.

4. The apparatus according to claim 1, wherein the camera posture determining unit is configured to determine an actual camera angle based on the relationship between camera angles estimated by the first and second posture estimating units, the actual camera angle, and a component in a direction of rotation of the deviation amount of the calibration sheet calculated by the sheet deviation calculating unit.

5. The apparatus according to claim 1, wherein the camera posture determining unit determines the posture of the camera based on a posture estimated value obtained by the first posture estimating unit.

6. The apparatus according to claim 1, wherein the vehicle is moved in a straight line.

7. The apparatus according to claim 1, further comprising:

a display processing unit configured to display a check image on a display, the check image used to determine whether the vehicle has been moved by the predetermined distance.

8. The apparatus according to claim 7,

wherein the check image includes a marker that moves in the check image as the vehicle is moved, and an auxiliary line having a display position fixed in the check image, and

wherein the check image is displayed such that the marker coincides with the auxiliary line when the movement of the vehicle by the predetermined distance is completed.

9. The apparatus according to claim 1, further comprising:

a movement completion determining unit that determines based on images captured by the camera whether the movement of the vehicle by the predetermined distance is completed, and provides a notification on completion of the movement.

10. A method for detecting the posture of a camera mounted on a vehicle based on images of a plurality of calibration marks included in a calibration sheet placed near the vehicle, the images captured by the camera, the method comprising:

estimating, by first posture estimating component, the posture of the camera based on an image of the calibration sheet captured by the camera;

estimating, by second posture estimating component, the posture of the camera based on an image of the calibration sheet captured by the camera after movement of the vehicle by a predetermined distance;

calculating, by a sheet deviation calculating component, an amount of deviation of the calibration sheet from a predetermined position based on estimations by the first and second posture estimating components; and

determining, by the camera posture determining component, the posture of the camera based on a posture estimated value obtained by at least one of the first and second posture estimating components and the deviation amount calculated by the sheet deviation calculating component.

11. An in-vehicle camera apparatus configured to detect a posture of a camera mounted on a vehicle, the apparatus comprising:

a calibration sheet having a plurality of calibration marks thereon;

a first image storing unit configured to store a calibration sheet image captured when the calibration sheet is placed at a predetermined location relative to the vehicle;

a first posture estimating unit configured to estimate the posture of the camera based on the calibration sheet image;

a second image storing unit configured to store a displaced calibration sheet image after the vehicle has moved by a predetermined distance relative to the calibration sheet;

a second posture estimating unit configured to estimate the posture of the camera based on the displaced calibration sheet image;

a sheet deviation calculating unit configured to calculate an amount of deviation of the calibration sheet from a predetermined position based on the estimates provided by the first and second posture estimating units; and

a camera posture determining unit configured to determine the posture of the camera based on a posture estimated value obtained by at least one of the first and second posture estimating units and the calculated amount of deviation.