Surrounding image generating apparatus and method of adjusting metering for image pickup device

• US 7,663,476 B2
• Filed: 04/27/2007
• Issued: 02/16/2010
• Est. Priority Date: 05/17/2006
• Status: Active Grant

• Current Assignee: Alpine Electronics Incorporated (Alps Alpine Co., Ltd.)
• Original Assignee: Alpine Electronics Incorporated (Alps Alpine Co., Ltd.)
• Inventors: Nomura, Tsubasa, Watanabe, Hisayuki
• Primary Examiner(s): Goins; Davetta W
• Assistant Examiner(s): Lau; Hoi C
• Application Number:
  US11/741,310
• Publication Number:
  US 20070268118A1
• Time in Patent Office: 1,026 Days
• Field of Search: 340/435, 340/436, 340/907, 340/932.2, 340/937, 348/148, 348/584, 348/149, 348/104, 348/153, 348/118, 382/104, 382/284, 382/154, 382/148
• US Class Current: 340/435
• CPC Class Codes: B60Q 9/005 using a video camera
• CPC Class Codes: B60R 1/27 providing all-round vision, e.g. using omnidirectional cameras
• CPC Class Codes: B60R 2300/102 using 360 degree surveillance camera system
• CPC Class Codes: B60R 2300/105 using multiple cameras
• CPC Class Codes: B60R 2300/302 combining image information with GPS information or vehicle data, e.g. vehicle speed, gyro, steering angle data
• CPC Class Codes: B60R 2300/303 using joined images, e.g. multiple camera images
• CPC Class Codes: B60R 2300/305 merging camera image with lines or icons
• CPC Class Codes: B60R 2300/8093 for obstacle warning
• CPC Class Codes: H04N 7/181 for receiving images from a plurality of remote sources

Abstract

A surrounding image generating apparatus changes a viewpoint of images around a vehicle, taken by multiple image pickup devices mounted at different positions along the vehicle, to generate a surrounding image of the areas around the vehicle viewed from a virtual viewpoint located above the vehicle. The surrounding image generating apparatus includes a metering area determining unit determining at least one overlapping area in which the shooting areas of the image pickup devices are overlapped with each other to be a metering area for at least part of the image pickup devices; an exposure calculating unit focusing metering on the metering area for the at least part of the image pickup devices to calculate an appropriate exposure of each of the image pickup devices; and a surrounding image generating unit generating the surrounding image by using image signals generated in accordance with the calculated exposures.

Claims

1. A surrounding image generating apparatus that changes a viewpoint of images taken by a plurality of image pickup devices mounted at different positions along a vehicle to generate a surrounding image showing areas around the vehicle as viewed from a virtual viewpoint located above the vehicle, the surrounding image generating apparatus comprising:

a metering area determining unit operable to determine at least one overlapping area in which a shooting area of at least two of the plurality of image pickup devices are overlapped with each other, the at least one overlapping area being set as a metering area that facilitates calculation of an appropriate exposure for both of the at least two of the plurality of image pickup devices;

an exposure calculating unit operable to calculate an appropriate exposure for both of the at least two of the plurality of image pickup devices on the basis of imaging signals associated with the metering area; and

a surrounding image generating unit operable to generate the surrounding image, wherein focusing of the metering on the at least one overlapping area to facilitate the calculation of the appropriate exposures for both of the at least two of the plurality of image pickup devices results in acquiring images including the at least one overlapping area taken from both of the at least two of the plurality of image pickup devices having similar luminance values in the at least one overlapping area from which the surrounding image is generated and that difference in luminance of the at least one overlapping area shown in the images acquired from both of the at least two of the plurality of image pickup devices is alleviated without pixel compensation.

2. The surrounding image generating apparatus according to claim 1, further comprising:

a traveling direction estimating unit that estimates a traveling direction of the vehicle,

wherein the metering area determining unit determines the at least one overlapping area to be in the traveling direction.

3. The surrounding image generating apparatus according to claim 2, wherein the traveling direction estimating unit estimates the traveling direction on the basis of a gear position of the vehicle.

4. The surrounding image generating apparatus according to claim 2, wherein the traveling direction estimating unit estimates the traveling direction on the basis of a gear position of the vehicle and which direction indicator is operating.

5. The surrounding image generating apparatus according to claim 1, further comprising:

an obstacle detecting unit that detects an obstacle in the vicinity of the vehicle,

wherein the metering area determining unit determines the at least one overlapping area to be in the direction toward where the obstacle is detected.

6. The surrounding image generating apparatus according to claim 5, further comprising:

a traveling direction estimating unit that estimates a traveling direction of the vehicle,

wherein the metering area determining unit determines the at least one overlapping area to also be in the traveling direction.

7. The surrounding image generating apparatus according to claim 1, wherein the metering area determining unit determines an area broader than the at least one overlapping area by a predetermined amount to be the metering area.

8. A method of adjusting metering for a plurality of image pickup devices mounted at different positions in and/or on a vehicle in order to generate a surrounding image showing areas around the vehicle as viewed from a virtual viewpoint located above the vehicle, the method comprising:

estimating a traveling direction of the vehicle;

determining at least one overlapping area for each of the plurality of image pickup devices, the at least one overlapping area comprising an overlapping shooting area in the estimated traveling direction;

focusing metering for each of the plurality of image pickup devices to the at least one overlapping area to facilitate calculation of an appropriate exposure for each of the plurality of image pickup devices; and

acquiring images of the at least one overlapping area from each of the plurality of image pickup devices with the appropriate exposure such that images of the at least one overlapping area taken from different image pickup devices have a similar luminance value and that difference in luminance of the at least one overlapping area shown in surrounding images showing the at least one overlapping area taken from different image pickup devices is alleviated without pixel compensation.

9. The method of adjusting metering according to claim 8, wherein the traveling direction is estimated on the basis of a gear position of the vehicle.

10. The method of adjusting metering according to claim 8, wherein the traveling direction is estimated on the basis of a gear position of the vehicle and which direction indicator is operating.

11. The method of adjusting metering according to claim 8, the method further comprising:

detecting an obstacle in the vicinity of the vehicle,

wherein the overlapping shooting area is also in the direction toward where the obstacle is detected.

12. The method of adjusting metering according to claim 8, wherein an area broader than the at least one overlapping area by a predetermined amount is determined to be the metering area.

13. A method of adjusting metering for a plurality of image pickup devices mounted at different positions along a vehicle in order to generate a surrounding image of the vehicle as viewed from a virtual viewpoint located above the vehicle, the method comprising:

detecting an obstacle in the vicinity of the vehicle;

determining an overlapping area for two image pickup devices, the overlapping area comprising an overlapping shooting area in the direction toward where the obstacle is detected; and

automatically focusing metering for both of the two image pickup devices on the overlapping area to facilitate the calculation of an appropriate exposure for both of the two image pickup devices on the basis of imaging signals of the overlapping area such that a luminance of the overlapping area shown in images taken from each of the two image pickup devices is similar and that difference in luminance of the overlapping area shown in surrounding images generated using the images taken from each of the two image pickup devices is alleviated without pixel compensation.

14. The method of adjusting metering according to claim 13, wherein the overlapping shooting area is also in the direction of vehicle travel.

15. The method of adjusting metering according to claim 14, wherein the direction of vehicle travel is estimated on the basis of a gear position of the vehicle.

16. The method of adjusting metering according to claim 13, wherein an area broader than the at least one overlapping area by a predetermined amount is determined to be the metering area.