Image synthesis display method and apparatus for vehicle camera

• US 20020196340A1
• Filed: 04/23/2002
• Published: 12/26/2002
• Est. Priority Date: 04/24/2001
• Status: Active Grant

• Current Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Inventors: Suzuki, Makoto, Kato, Koichi, Fujita, Yukio, Hirama, Yuichi
• Granted Patent: US 7,139,412 B2
• Time in Patent Office: Days
• US Class Current: 348/148
• CPC Class Codes: B60R 1/00 Optical viewing arrangements; Real-time viewing arrangements for drivers or passengers using optical image capturing systems, e.g. cameras or video systems specially adapted for use in or on vehicles
• CPC Class Codes: B60R 1/26 to the rear of the vehicle
• CPC Class Codes: B60R 2300/105 using multiple cameras
• CPC Class Codes: B60R 2300/303 using joined images, e.g. multiple camera images
• CPC Class Codes: B60R 2300/607 from a bird's eye viewpoint
• CPC Class Codes: G06T 2207/30252 Vehicle exterior; Vicinity of vehicle
• CPC Class Codes: G06T 3/4038 Image mosaicing, e.g. composing plane images from plane sub-images
• CPC Class Codes: G06T 7/30 Determination of transform parameters for the alignment of images, i.e. image registration
• CPC Class Codes: H04N 7/181 for receiving images from a plurality of remote sources

Abstract

When multiple cameras (CAM1) to (CAM8) for shooting the periphery of a local vehicle are mounted on the vehicle, and when obtained camera images are to be synthesized to display a synthesized image on the screen of a display device (16), the pixel data for the camera images constituting the synthesized image are compensated for, so that differences in the pixel data for adjacent camera images is reduced. For example, the pixel data are corrected so their values equal the average values of the pixel data for the adjacent camera images. Therefore, an easily viewed image, produced by synthesizing the images obtained by the multiple vehicle cameras, can be displayed on the monitor device (16).

Claims

1. An image synthesis display method for a vehicle camera comprising the steps of:

synthesizing images obtained by a plurality of vehicle cameras shooting the periphery of a local vehicle;

displaying a synthesized image on the screen of a display device,

wherein the synthesized image of the plurality of vehicle cameras is displayed on the screen by performing a compensation to reduce differences between pixel data of the adjacent camera images of the plurality of vehicle cameras.

2. The image synthesis display method according to claim 1, wherein the compensation to reduce differences is performed to each equalize average value of pixel data of the adjacent camera images of the plurality of vehicle cameras.

3. The image synthesis display method according to claim 2, wherein the average values are obtained by using the entire pixel data of at least one of said adjacent camera images.

4. An image synthesis display method according to claim 2, wherein the average values are obtained by using pixel data of a vicinity of the local vehicle in the entire pixel data of at least one of the adjacent camera images.

5. The image synthesis display method according to claim 2, wherein the average values are obtained by using the pixel data of the overlapping shooting regions of the adjacent camera images.

6. The image synthesis display method according to claim 2, wherein the average values are obtained by using pixel data of the vicinity of said local vehicle in pixel data of the overlapping shooting regions of the adjacent camera images.

7. The image synthesis display method according to claim 2, wherein a flag table is prepared in correlation with pixel positions for the plurality of vehicle cameras, and the average values are obtained by using pixel data displayed at pixel positions that correspond to pixel areas written in advance in the flag table.

8. The image synthesis display method according to claim 1, wherein the values of the image data for which said differences are to be reduced represent brightness or colors.

9. The image synthesis display method according to claim 1, wherein the compensation is performed to gradually reduce differences along the time axis near a target compensation value.

10. The image synthesis display method according to claim 1,

wherein, when three or more vehicle cameras are prepared, a camera image whose average value is nearest the average value for pixel data for all the camera images is regarded as a reference image,

wherein the compensation of the image data of the adjacent camera images are performed to adjust to the average value for the reference image.

11. The image synthesis display method according to claim 1, wherein the synthesized image is a synthesized image by synthesizing images of which a view point is changed.

12. An image synthesis display apparatus for a vehicle camera, wherein images obtained by a plurality of vehicle cameras shooting a periphery of a local vehicle are synthesized and the synthesized image is displayed on the screen of a display device, comprising:

compensation means which carrying out an image synthesis display method according to claim 1.