On-vehicle camera calibration device

• US 6,813,371 B2
• Filed: 12/26/2000
• Issued: 11/02/2004
• Est. Priority Date: 12/24/1999
• Status: Active Grant

• Current Assignee: Aisin Seiki Co., Ltd. (Aisin Corp.)
• Original Assignee: Aisin Seiki Co., Ltd. (Aisin Corp.)
• Inventors: Kakinami, Toshiaki
• Primary Examiner(s): Mehta, Bhavesh M.
• Assistant Examiner(s): Tabatabai, Abolfazl
• Application Number:
  US09/745,807
• Publication Number:
  US 20010006554A1
• Time in Patent Office: 1,407 Days
• Field of Search: 382/100, 382/103, 382/104, 382/106, 382/107, 382/152, 382/199, 340/901, 340/902, 340/903, 340/904, 340/907, 340/438, 340/439, 340/938, 340/939, 340/988, 701/23, 701/28, 701/29, 701/36, 701/40, 701/41, 701/44, 701/70, 701/93, 701/96, 701/98, 701/116, 701/117, 701/225, 348/113, 348/149
• US Class Current: 382/104
• CPC Class Codes: G01S 11/12 using electromagnetic waves other than radio waves
• CPC Class Codes: G01S 7/4972 Alignment of sensor
• CPC Class Codes: G06T 2200/24 involving graphical user interfaces [GUIs]
• 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 on-vehicle camera calibration device is provided and a method of calibrating an on-vehicle camera easily is carried out by using a calibration indicator other than a three dimensional one. The calibration indicator makes it possible to set camera parameters to form an image on an arbitrary portion of a screen. The calibration indicator is in the form of a planar calibration indicator TB. A camera picked-up image including the calibration indicator TB is displayed on a screen on which a window is also displayed in superposed fashion. The position of the window is changed in a 2D image coordinate system. The position of the window is adjusted by manipulating an adjust button 7 so that the calibration indicator TB falls within the window. When the calibration indicator TB is placed in the window in coincident fashion, the resultant camera parameters (unknown roll θ r, tilt angle θ t, and pan angle θ p) are set as camera parameters of the camera 17.

Claims

1. A camera calibration device for calibrating an on-vehicle camera based on an object placed in an image picked up by the on-vehicle camera comprising:

a planar calibration indicator as the object;

displaying means for displaying the image including the planer calibration indicator;

window displaying means for displaying a window on the displaying means;

adjusting means for adjusting a position of the window displaying means within a coordinate of the image picked up by the on-vehicle camera; and

parameter setting means for setting camera parameters such that when the calibration indicator is within the window as a result of the adjusting by the adjusting means, the resultant camera parameters are employed as the camera parameters.

2. A camera calibration method as set forth in claim 1, wherein said parameter setting means sets camera parameters such that when at least two points of the calibration indicator are within the window as a result of the adjusting by the adjusting means, the resultant camera parameters are employed as the camera parameters.

3. A camera calibration method as set forth in claim 2, wherein said each of the two points is an end of the planar calibration indicator.

4. A camera calibration method of calibrating an on-vehicle camera based on an object placed in an image picked up by the on-vehicle camera comprising the steps of;

preparing a planar calibration indicator as the object, displaying means for displaying the image including the planer calibration indicator, window displaying means for displaying a window on the displaying means, and adjusting means for adjusting a position of the window displaying means within a coordinate of the image picked up by the on-vehicle camera;

displaying the planar calibration indicator on the displaying means;

adjusting a related position of the window so as to include the planar calibration indicator therein; and

setting camera parameters when the planar calibration indicator is located in the window.

5. A camera calibration method as set forth in claim 4, wherein the adjustment of the position relation of the window is made such that the window is rotated or shifted relative to the planar calibration indicator.

6. A camera calibration method as set forth in claim 4, wherein said setting camera parameters is when at least two points of the planar calibration indicator are located on the window.

7. A camera calibration method as set forth in claim 6, wherein said each of the two points is an end of the planar calibration indicator.

8. A calibration indicator displayed as a movable image related to vehicular travel on an on-vehicle displaying device in a superposed manner on a picked up scene image of the outside of the vehicle and is displayed and used a part of the movable images as an indicator when camera parameters are set.

9. A calibration indicator as set forth in claim 8, wherein the movable image is a forecast vehicle travel path which varies with a steering angle.