IMAGING APPARATUS, IMAGE PROCESSING APPARATUS, IMAGE PROCESSING METHOD, AND RECORDING MEDIUM THAT RECORDS IMAGE PROCESSING PROGRAM

• US 20190327429A1
• Filed: 07/01/2019
• Published: 10/24/2019
• Est. Priority Date: 03/09/2017
• Status: Active Grant

• Current Assignee: Olympus Corporation
• Original Assignee: Olympus Corporation
• Inventors: ONOMURA, Kenichi
• Granted Patent: US 11,102,427 B2
• Time in Patent Office: Days
• CPC Class Codes: H04N 23/10 for generating image signals from different wavelengths
• CPC Class Codes: H04N 23/60 Control of cameras or camera modules
• CPC Class Codes: H04N 23/843 Demosaicing, e.g. interpolating colour pixel values
• CPC Class Codes: H04N 25/40 Extracting pixel data from image sensors by controlling scanning circuits, e.g. by modifying the number of pixels sampled or to be sampled
• CPC Class Codes: H04N 25/704 Pixels specially adapted for focusing, e.g. phase difference pixel sets

Abstract

An imaging apparatus includes a solid-state image sensor with Bayer array structure. The imaging apparatus includes a calculation circuit, an interpolation operating circuit, and a G-step detecting circuit. The calculation circuit calculates a first value and a second value, for each predetermined image area of image data output from the solid-state image sensor. The first value is a mean value or integrated value of pixel values of first green pixels. The second value is a mean value or integrated value of pixel values of second green pixels. The interpolation operating circuit performs, for a plurality of the image areas, an interpolation operation by using a plurality of the first values and a plurality of the second values.

Claims

1. An imaging apparatus comprising a solid-state image sensor with Bayer array structure in which a first line, where red pixels and first green pixels are alternately arranged in a horizontal direction, and a second line, where blue pixels and second green pixels are alternately arranged in the horizontal direction, are alternately arranged in a vertical direction, the imaging apparatus comprising:

a calculation circuit configured to calculate a first value and a second value, for each predetermined image area of image data output from the solid-state image sensor, the first value being a mean value or integrated value of pixel values of the first green pixels, the second value being a mean value or integrated value of pixel values of the second green pixels;

an interpolation operating circuit configured to perform, for a plurality of the image areas, an interpolation operation by using the first values and the second values such that a first center of gravity represented by each of the first values and a second center of gravity represented by each of the second values match each other; and

a G-step detecting circuit configured to calculate a difference between the first value and the second value interpolated.

2. The imaging apparatus according to claim 1, wherein

the calculation circuit calculates, for two of the image areas whose positions are apart from each other by 2 pixels in each of the horizontal and vertical directions, two of the first values and two of the second values.

3. The imaging apparatus according to claim 2, wherein

the calculation circuit determines a direction to which one of the two image areas is to be shifted in accordance with a head color of the other of the two image areas.

4. The imaging apparatus according to claim 1, wherein

the calculation circuit calculates, for four of the image areas, four of the first values and four of the second values, and

from a first of the image area of the four image areas, a second of the image area is shifted by 2 pixels in the horizontal direction, a third of the image area is shifted by 2 pixels in the vertical direction, and a fourth of the image area is shifted by 2 pixels in each of the horizontal and vertical directions.

5. The imaging apparatus according to claim 1, wherein

the calculation circuit calculates the first value and the second value by excluding a different pixel, the different pixel being different from a normal first green pixel exists at a position of the first green pixel or a normal second green pixel exists at a position of the second green pixel in the image area.

6. An image processing apparatus comprising:

a calculation circuit configured to calculate a first value and a second value, for each predetermined image area of image data output from a solid-state image sensor with Bayer array structure in which a first line, where red pixels and first green pixels are alternately arranged in a horizontal direction, and a second line, where blue pixels and second green pixels are alternately arranged in the horizontal direction, are alternately arranged in a vertical direction, the first value being a mean value or integrated value of pixel values of the first green pixels and the second value being a mean value or integrated value of pixel values of the second green pixels;

an interpolation operating circuit configured to perform, for a plurality of the image areas, an interpolation operation by using a plurality of the first values and a plurality of the second values such that a first center of gravity represented by each of the first values and a second center of gravity represented by each of the second values match each other; and

a G-step detecting circuit configured to calculate a difference between the first value and the second value interpolated.

7. The image processing apparatus according to claim 6, wherein

the calculation circuit calculates, for two of the image areas whose positions are apart from each other by 2 pixels in each of the horizontal and vertical directions, two of the first values and two of the second values.

8. An image processing method comprising:

calculating a first value and a second value, for each predetermined image area of image data output from a solid-state image sensor with Bayer array structure in which a first line, where red pixels and first green pixels are alternately arranged in a horizontal direction, and a second line, where blue pixels and second green pixels are alternately arranged in the horizontal direction, are alternately arranged in a vertical direction, the first value being a mean value or integrated value of pixel values of the first green pixels and the second value being a mean value or integrated value of pixel values of the second green pixels;

performing an interpolation operation by using a plurality of the first values and a plurality of the second values calculated for a plurality of the image areas such that a first center of gravity represented by each of the first values and a second center of gravity represented by each of the seconds match each other; and

calculating a difference between the first value and the second value interpolated by the interpolation operation.

9. The image processing method according to claim 8, wherein

the calculating the first value and the second value includes calculating, for two of the image areas whose positions are apart from each other by 2 pixels in each of the horizontal and vertical directions, two of the first values and two of the second values.

10. A computer readable recording medium that records an image processing program for causing a computer to execute:

calculating a first value and a second value, for each predetermined image area of image data output from a solid-state image sensor with Bayer array structure in which a first line, where red pixels and first green pixels are alternately arranged in a horizontal direction, and a second line, where blue pixels and second green pixels are alternately arranged in the horizontal direction, are alternately arranged in a vertical direction, the first value being a mean value or integrated value of pixel values of the first green pixels and a second value being a mean value or integrated value of pixel values of the second green pixels;

performing an interpolation operation by using a plurality of the first values and a plurality of the second values calculated for a plurality of the image areas such that a first center of gravity represented by each of the plurality of the first values and a second center of gravity represented by each of the plurality of the second values match each other; and

calculating a difference between the first value and the second value interpolated by the interpolation operation.

11. The recording medium according to claim 10, wherein

the calculating the first value and the second value includes calculating, for two of the image areas whose positions are apart from each other by 2 pixels in each of the horizontal and vertical directions, two of the first values and two of the second values.