Image capture apparatus and program

• US 8,711,230 B2
• Filed: 04/16/2009
• Issued: 04/29/2014
• Est. Priority Date: 05/16/2008
• Status: Expired due to Fees

• Current Assignee: Casio Computer Company Limited
• Original Assignee: Casio Computer Company Limited
• Inventors: Matsunaga, Kazuhisa
• Primary Examiner(s): Berhan, Ahmed A
• Application Number:
  US12/424,769
• Publication Number:
  US 20090284609A1
• Time in Patent Office: 1,839 Days
• Field of Search: 348/208.99, 348/208.1, 348/208.6, 348/208.12, 348/208.11, 348/208.4, 348/208.13, 348/208.5, 348 36- 39, 348/218.1, 348/362, 348/221.1, 396/55
• US Class Current: 348/208.13
• CPC Class Codes: H04N 23/68 for stable pick-up of the scene, e.g. compensating for camera body vibrations
• CPC Class Codes: H04N 23/6812 based on additional sensors, e.g. acceleration sensors
• CPC Class Codes: H04N 23/687 by shifting the lens or sensor position
• CPC Class Codes: H04N 25/67 applied to fixed-pattern noise, e.g. non-uniformity of response

Abstract

An image capture apparatus shifts an image sensor at each shooting initiation time in the continuous-shoot mode in the event of a camera-shake in response to a control signal which reflects an offset signal indicating pixel shifting information in a compensating signal indicating shake compensating information. Thereby, a change in the shooting range of the image sensor due to the camera-shake is mostly compensated for and the shooting range is changed by one pixel at each shooting. Thus, even in the event of a camera-shake, the distance between a feature portion of a main subject and a fixed pattern noise can be made different for each of continuously shot images. As a result, even in the event of the camera-shake, a composite image having fixed pattern noises scattered can be obtained by combining continuously shot images with reference to the feature portion.

Claims

1. An image capture apparatus comprising:

an image producing unit configured to shoot a subject a number of times successively with an image sensor to produce a plurality of images;

a compensating unit configured to change a relative position of the image producing unit and an optical axis of the image producing unit such that (i) a displacement of a shooting range of the image sensor is compensated for and (ii) the shooting range of the image sensor varies for each shooting during the successive shooting of the subject; and

a composite image forming unit configured to combine the plurality of images, having been produced with the displacement compensated for by the compensating unit, with reference to a common main subject portion in the images of the subject as a reference position for combining the images so as to create a composite image of the plurality of images having reduced fixed pattern noises.

2. The image capture apparatus according to claim 1, wherein the compensating unit includes:

a first output unit configured to detect a camera-shake and output shake compensating information to compensate for the displacement in a position of the image sensor due to the camera-shake,

a second output unit configured to output pixel shifting information to shift the position of the image sensor,

a calculation unit configured to calculate shift information of the image sensor which reflects the shake compensating information and the pixel shifting information, and

a shift controlling unit configured to shift the position of the image sensor in accordance with the shift information calculated by the calculation unit,

wherein the compensating unit is configured to change the relative position of the image producing unit and the optical axis of the image producing unit by moving the image sensor via the shift controlling unit.

3. The image capture apparatus according to claim 2, wherein the second output unit is configured to output pixel shifting information to shift the image sensor in a given direction at a first-image shooting time and to output pixel shifting information to shift the image sensor in a direction opposite to the given direction at a second-image shooting time and thereafter.

4. The image capture apparatus according to claim 3, wherein the second output unit is configured to output pixel shifting information to shift the image sensor in the given direction by a first shift amount at the first-image shooting time and to output pixel shifting information to shift the image sensor in the direction opposite to the given direction by a second shift amount smaller than the first shift amount at the second-image shooting time and thereafter.

5. The image capture apparatus according to claim 4, wherein the second output unit is configured to output the pixel shifting information only at each image shooting initiation time.

6. The image capture apparatus according to claim 2, wherein the second output unit is configured to output pixel shifting information for shifting the position of the image sensor by at least a number of pixels corresponding to a pattern width of the fixed pattern noise of the images.

7. The image capture apparatus according to claim 1, further comprising an extraction unit configured to extract respective feature portions from each common main subject portion in the images of the subject produced by the image producing unit, and

wherein the composite image forming unit is configured to combine the images with reference to the extracted feature portions extracted by the extraction unit as a reference position for combining the images to create the composite image.

8. The image capture apparatus according to claim 7, further comprising an erase unit configured to erase an image in which the main subject is not taken from among the plurality of images produced by the image producing unit, and

wherein the composite image forming unit is configured to combine the images, excluding the erased image in which the main subject is not taken, with reference to the feature portions extracted by the extraction unit as a reference position for combining the images to create the composite image.

9. The image capture apparatus according to claim 1, wherein the composite image forming unit is configured to combine the images with reference to the common main subject portion of the images of the subject so that brightness and color difference values of the composite image are average values of brightness and color difference values of the plurality of images.

10. A non-transitory computer readable recording medium having recorded thereon a computer program that is executable by a computer provided in an image capture apparatus comprising image producing means for shooting a subject successively a number of times using an image sensor to produce a plurality of images, the computer program causing the computer to execute processes comprising:

a compensating process of changing a relative position of the image producing means and an optical axis of the image producing means such that (i) a displacement of a shooting range of the image sensor is compensated for and (ii) the shooting range of the image sensor varies for each shooting during the successive shooting of the subject; and

a composite image forming process of combining the plurality of images with reference to common subject portions of the images of the subject as a reference position for combining the images, having been produced with the displacement compensated for by the compensating process, to create a composite image of the produced plurality of images having reduced fixed pattern noises.