Imaging device and imaging device control method

• US 8,648,926 B2
• Filed: 11/18/2010
• Issued: 02/11/2014
• Est. Priority Date: 11/25/2009
• Status: Active Grant

• Current Assignee: OM Digital Solutions Corporation
• Original Assignee: Olympus Imaging Corporation (Olympus Corporation)
• Inventors: Kunishige, Keiji, Shimada, Yoshinao, Honda, Tsutomu
• Primary Examiner(s): Ye, Lin
• Assistant Examiner(s): Chon, Peter
• Application Number:
  US12/949,067
• Publication Number:
  US 20110122287A1
• Time in Patent Office: 1,181 Days
• Field of Search: 348/222.1, 348/239, 348/345, 348/346, 348/347, 348/348, 348/349, 348/350, 348/351, 348/352, 348/353, 348/354, 348/355, 348/356, 348/241, 348/294, 348/295, 348/296, 348/297
• US Class Current: 348/222.1
• CPC Class Codes: H04N 1/00114 with transmission of additional information signals for control or supervision between transmitter and receiver H04N1/32101
• CPC Class Codes: H04N 1/2112 using still video cameras
• CPC Class Codes: H04N 23/63 by using electronic viewfinders
• CPC Class Codes: H04N 23/673 based on contrast or high frequency components of image signals, e.g. hill climbing method
• CPC Class Codes: H04N 23/743 Bracketing, i.e. taking a series of images with varying exposure conditions
• CPC Class Codes: H04N 23/75 by influencing optical camera components
• CPC Class Codes: H04N 23/76 by influencing the image signals
• CPC Class Codes: H04N 25/53 Control of the integration time
• CPC Class Codes: H04N 25/531 by controlling rolling shutters in CMOS SSIS
• CPC Class Codes: H04N 9/74 for obtaining special effects H04N9/65 - H04N9/73 take precedence

Abstract

An imaging device of the present invention comprises an imaging section for photoelectrically converting a subject image, and outputting image data, an aperture control section for narrowing subject light flux at a first aperture value and a second aperture value, a shooting control section for, in response to a release instruction, imaging a first image at the first aperture value and, reading out first image data from the imaging section while simultaneously carrying out a stopping down operation to the second aperture value, imaging a second image at the second aperture value and, reading out second image data from the imaging section, and an image processing section for detecting an amount of variation in contrast value for each location in the first image data and the second image data, and carrying out processing to blur at an intensity of blurring according to the amount of variation between each location.

Claims

1. An imaging device, comprising:

an imaging section for photoelectrically converting a subject image formed by a photographing lens and outputting image data;

an aperture control section, arranged on the optical path of the photographing lens, for narrowing subject light flux at a first aperture value and a second aperture value;

a shooting control section for, in response to a release instruction, imaging a first image at the first aperture value and, after completion of imaging of the first image, reading out first image data from the imaging section while at the same time carrying out a stopping operation to the second aperture value using the aperture control section, imaging a second image at the second aperture value and, after completion of imaging of the second image, reading out second image data from the imaging section; and

an image processing section for detecting an amount of variation in contrast value for each location in the first image data and the second image data, and carrying out processing to blur at an intensity of blurring according to the amount of variation for each location in the first image data and the second image data,

wherein, the shooting control section acquires image data at the time of reset of each pixel of the imaging section before imaging of the first image, and creates the first image data by removing the image data for each pixel at the time of reset from the first image data for each pixel that has been acquired by the imaging section, after imaging of the first image, and

the aperture control section carries out a stopping operation to the first aperture value simultaneously with the imaging control section reading out image data at the time of the reset from the imaging section.

2. The imaging device of claim 1, further wherein:

the imaging section has a global shutter function.

3. The imaging device of claim 1, further wherein:

the first aperture value is a wide-open aperture value.

4. The imaging device of claim 1, further wherein:

the image processing section sets a specified evaluation pixel for first and second image data, and sets an evaluation area comprised of pixels surrounding the evaluation pixel, sums information relating to differences between data of the evaluation pixel and data of the surrounding pixels, within the evaluation area, and calculates contrast values for each of the locations.

5. The imaging device of claim 4, further wherein:

the image processing section makes a difference in contrast values at each location in the first image data and the second image data the amount of variation.

6. The imaging device of claim 1, wherein:

the image processing device executes the blurring processing for RAW image data that has been output from the imaging section, or for RGB image data resulting from processing of the RAW image data, or for YCC image data resulting from processing of the RGB image data.

7. The imaging device of claim 1, wherein:

the image processing section executes the blurring process after carrying out image expansion processing, for JPEG image data that has been generated based on image data output from the imaging section.

8. The imaging device of claim 1, further comprising:

a storage section for storing image data, and wherein the image processing section stores image data in the storage section, and stores amounts of variation in the contrast values between the first aperture value and the second aperture value, relating to blurring processing of the image data, in the storage section.

9. The imaging device of claim 8, wherein

the image processing section stores amounts of variation in the contrast values for each of R, G and B in the storage section.

10. The imaging device of claim 8, wherein

the image processing section stores image data after the blurring processing has been carried out in the storage section.

11. The imaging device of claim 10, wherein

the image processing section stores amounts of variation in the contrast values for each of R, G and B in the storage section.

12. The imaging device of claim 8, wherein

the image processing section stores RAW image data before carrying out the blurring processing in the storage section.

13. The imaging device of claim 12, wherein:

the image processing section stores amounts of variation in the contrast values for each of R, G and B in the storage section.

14. The imaging device of claim 1, further comprising:

a display section for carrying out live view display based on the image data output from the imaging section; and

a second diaphragm section arranged close to a diaphragm controlled by the diaphragm control section, wherein the exposure control section changes between the first aperture value and the second aperture value using the second diaphragm section during live view display, and the image processing section carries out the blurring processing based on the image data acquired by the imaging section, while the display section carries out live view display based on image data that has been subjected to the blurring processing.

15. The imaging device of claim 1, wherein:

an image sensor of the imaging section is comprised of photoelectric conversion elements corresponding to each pixel, and a charge accumulation section, wherein the exposure control section controls exposure time when taking the first image and the second image by controlling accumulation time of the charge accumulation section.

16. The imaging device of claim 1, wherein the release instruction is a caused by a user pressing a release button to cause a second release switch to be turned on.

17. An imaging device, comprising:

an imaging section for photoelectrically converting a subject image formed by a photographing lens and outputting image data;

an aperture control section, arranged on the optical path of the photographing lens, for narrowing subject light flux at a first aperture value and a second aperture value;

a shooting control section for, in response to a release instruction, imaging a first image at the first aperture value and, after completion of imaging of the first image, reading out first image data from the imaging section while at the same time carrying out a stopping down operation to the second aperture value using the aperture control section, imaging a second image at the second aperture value and, after completion of imaging of the second image, reading out second image data from the imaging section;

an image processing section for detecting an amount of variation in contrast value for each location in the first image data and the second image data, and carrying out processing to blur at an intensity of blurring according to the amount of variation for each location in the first image data and the second image data; and

a virtual aperture value setting section for setting a virtual aperture in order to adjust the blurring intensity,

wherein the image processing section calculates the blurring intensity in accordance with the amount of variation, based on a virtual aperture set by the virtual aperture value setting section.

18. The imaging device of claim 17, wherein:

the image processing section estimates a bokeh amount with the virtual aperture value in accordance with the amount of variation, and calculates blurring intensity based on the estimated bokeh amount.

19. The imaging device of claim 18, wherein:

blurring processing according to the blurring intensity is carried out for every evaluation pixel for all pixels of the first image data and the second image data.

20. An imaging device, comprising:

an imaging section for photoelectrically converting a subject image formed by a photographing lens and outputting image data;

an aperture control section, arranged on the optical path of the photographing lens, for narrowing subject light flux at a first aperture value and a second aperture value;

a shooting control section for, in response to a release instruction, imaging a first image at the first aperture value and, after completion of imaging of the first image, reading out first image data from the imaging section while at the same time carrying out a stopping down operation to the second aperture value using the aperture control section, imaging a second image at the second aperture value and, after completion of imaging of the second image, reading out second image data from the imaging section;

an image processing section for detecting an amount of variation in contrast value for each location in the first image data and the second image data, and carrying out processing to blur at an intensity of blurring according to the amount of variation for each location in the first image data and the second image data; and

a storage section for storing image data,

wherein the image processing section stores image data after the blurring processing has been carried out, and the first image data and the second image data, in the storage section, and stores file names of image files of the first image data and the second image data as identical objects with the same file name as the image file name of the image data after the blurring processing has been carried out.

21. A control method for an imaging device comprising the steps of:

carrying out imaging of a first image at a first aperture value, and reading out first image data after imaging of the first image has been completed, while simultaneously carrying out a stopping operation to drive a diaphragm from the first aperture value to a second aperture value;

carrying out imaging of a second image at the second aperture value, and reading out second image data after imaging of the second image has been completed; and

detecting an amount of variation in contrast values for each location in the first image data and the second image data, and carrying out processing to blur at an intensity of blurring according to the amount of variation between each location in the first image and the second image,

wherein, image data at the time of reset of each pixel is acquired before imaging of the first image, and the first image data for each pixel of the first image data that has been acquired by imaging of the first image is created by removing the image data for each pixel at the time of reset, and

a stopping operation to the first aperture value is carried out simultaneously with reading out of image data at the time of the reset from the imaging section.

22. An imaging device, comprising:

an imaging section for photoelectrically converting a subject image formed by a photographing lens and outputting image data;

an aperture control section, arranged on the optical path of the photographing lens, for narrowing subject light flux at a first aperture value and a second aperture value;

a shooting control section for, in response to a release instruction, imaging a first image at the first aperture value and, after completion of imaging of the first image, reading out first image data from the imaging section while at the same time carrying out a stopping operation to the second aperture value using the aperture control section, imaging a second image at the second aperture value and, after completion of imaging of the second image, reading out second image data from the imaging section; and

an image processing section for carrying out image processing for the first image data and the second image data that have been read out by the shooting control section,

wherein, the shooting control section acquires image data at the time of reset of each pixel of the imaging section before imaging of the first image, and creates the first image data by removing the image data for each pixel at the time of reset from the first image data for each pixel that has been acquired by the imaging section, after imaging of the first image, and

the aperture control section carries out a stopping operation to the first aperture value simultaneously with the imaging control section reading out image data at the time of the reset from the imaging section.

23. The imaging device of claim 22, wherein:

the image processing section detects an amount of variation in contrast values for each location in the first image data and the second image data, and carries out blurring processing an intensity of blurring according to the amount of variation between each location in the first image data and the second image data.

24. The imaging device of claim 22, wherein the release instruction is a caused by a user pressing a release button to cause a second release switch to be turned on.