Image-taking apparatus and image processing method

• US 20050195295A1
• Filed: 03/02/2005
• Published: 09/08/2005
• Est. Priority Date: 03/03/2004
• Status: Active Grant

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Kawai, Takashi
• Granted Patent: US 7,834,907 B2
• Time in Patent Office: Days
• US Class Current: 348/239
• CPC Class Codes: H04N 23/60 Control of cameras or camera modules
• CPC Class Codes: H04N 23/681 Motion detection
• CPC Class Codes: H04N 23/698 for achieving an enlarged field of view, e.g. panoramic image capture
• CPC Class Codes: H04N 5/2628 Alteration of picture size, shape, position or orientation, e.g. zooming, rotation, rolling, perspective, translation

Abstract

The object is to enable correction of image shift while reducing image quality deterioration as far as possible, in an image taking apparatus for converting a fisheye image to perspectively projected image. The image taking apparatus is capable of taking a first image in accordance with a first projection method and comprises: an image taking element for photoelectrically converting the first image; conversion means for converting an image in a conversion area in the first image acquired with the image taking element to a second image which is in accordance with a second projection method different from the first projection method; and vibration detection means for acquiring information about vibration of the image taking apparatus; wherein the conversion means changes the size of the conversion area based on the vibration information. The image taking apparatus comprises: an image taking element 102 for photoelectrically converting a fisheye image formed by a fisheye optical system; conversion means 114 for performing a process of projection conversion from fisheye image data acquired by the image taking element to perspectively projected image data; shaking detection means 110 for acquiring information about vibration; and image shift correction means 117 for shifting an area in the perspectively projected image data, which is to be outputted, based on the vibration information. The conversion means changes the size of the (conversion area in the fisheye image data, for which the projection conversion process is to be performed, based on the vibration means.

Claims

1. An image taking apparatus capable of taking a first image in accordance with a first projection method, the image taking apparatus comprising:

an image taking element for photoelectrically converting the first image;

conversion means for converting an image in a conversion area in the first image acquired with the image taking element to a second image which is in accordance with a second projection method different from the first projection method; and

vibration detection means for acquiring information about vibration of the image taking apparatus;

wherein the conversion means changes the size of the conversion area based on the vibration information.

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

image shift correction means for shifting an area in the second image, which is to be outputted, based oil the vibration information.

3. The image taking apparatus according to claim 1, wherein

the first image is a fisheye image and the second image is a perspectively projected image.

4. The image taking apparatus according to claim 1, wherein

the conversion means enlarges the conversion area as the vibration is larger.

5. The image taking apparatus according to claim 1, comprising:

zoom means for changing the zoom ratio of the first image;

wherein

the conversion means changes the size of the conversion area based on the vibration information and information about the zoom ratio.

6. The image taking apparatus according to claim 3, wherein

the conversion means reduces the conversion area as the zoom ratio is larger.

7. An image processing method comprising:

a conversion step of converting an image in a conversion area in a first image which is in accordance with a first projection method to a second image which is in accordance with a second projection method different from the first projection method; and

an detection step of acquiring information about a positional change of the first image on an image taking;

wherein

the conversion step changes the size of the conversion area based on the information about image shift.

8. The image processing method according to claim 7, further comprising:

a image shift correction step of shifting an area in the second image, which is to be outputted, based on the information about image shift.

9. The image processing method according to claim 7, wherein

the first image is a fisheye image and the second image is a perspectively projected image.

10. The image processing method according to claim 7, wherein

the conversion step enlarges the conversion area is the image shift is larger.

11. The image processing method according to claim 7, further comprising:

a zoom setting step of changing the zoom ratio of the first image;

wherein

the conversion step changes the size of the conversion area based on the information about image shift and information about the zoom ratio.

12. The image processing method according to claim 11, wherein

the conversion step reduces the conversion area as the zoom ratio is larger.

13. An image processing program for causing a computer to perform the image processing method according to claim 7.

14. An image taking apparatus capable of taking a first image in accordance with a first projection method, the image taking apparatus comprising:

an image taking element for photoelectrically converting the first image;

conversion means for converting an image in a conversion area in the first image acquired with the image talking element to a second image which is in accordance with a second projection method different from the first projection method; and

vibration detection means for acquiring information about vibration of the image taking apparatus;

wherein

the conversion means performs a reduction process for the second image at a reduction ratio corresponding to the vibration information.

15. The image taking apparatus according to claim 14, further comprising:

image shift correction means for shifting an area in the second image, which is to be outputted, based on the vibration information.

16. The image taking apparatus according to claim 14, wherein

the first image is a fisheye image and the second image is a perspectively projected image.

17. An image processing method comprising:

a conversion step of converting an image in a conversion area in a first image which is in accordance with a first projection method to a second image which is in accordance with a second projection method different from the first projection method; and

an image shift detection step of acquiring information about image shift in the first image;

wherein

the conversion step performs a reduction process for the second image at a reduction ratio corresponding to the vibration information.

18. The image processing method according to claim 17, further comprising:

a image shift correction step of shifting an area in the second image, which is to be outputted, based on the information about image shift.

19. The image processing method according to claim 17, wherein

the first image is a fisheye image and the second image is a perspectively projected image.

20. An image processing program for causing a computer to perform the image processing method according to claim 17.