Image correction apparatus

• US 20050271295A1
• Filed: 05/12/2005
• Published: 12/08/2005
• Est. Priority Date: 05/13/2004
• Status: Active Grant

• Current Assignee: Omron Corporation
• Original Assignee: Omron Corporation
• Inventors: Yoshida, Yoko, Tabata, Naohiro
• Granted Patent: US 7,539,342 B2
• Time in Patent Office: Days
• US Class Current: 382/274
• CPC Class Codes: G06T 2207/10024 Color image
• CPC Class Codes: G06T 2207/20012 Locally adaptive
• CPC Class Codes: G06T 2207/30201 Face
• CPC Class Codes: G06T 5/002 Denoising; Smoothing noise processing or correction adapted to be used in an image pickup device containing and electronic image sensor H04N23/81, H04N25/60 - H04N25/67
• CPC Class Codes: G06T 5/008 Local, e.g. shadow enhancement
• CPC Class Codes: G06T 5/40 using histogram techniques
• CPC Class Codes: G06T 5/70 Denoising; Smoothing
• CPC Class Codes: G06T 5/94 based on local image properties, e.g. for local contrast enhancement
• CPC Class Codes: G06T 7/136 involving thresholding
• CPC Class Codes: H04N 1/6086 by scene illuminant, i.e. conditions at the time of picture capture, e.g. flash, optical filter used, evening, cloud, daylight, artificial lighting, white point measurement, colour temperature
• CPC Class Codes: H04N 1/62 Retouching, i.e. modification of isolated colours only or in isolated picture areas only
• CPC Class Codes: H04N 1/628 Memory colours, e.g. skin or sky

Abstract

An object of the invention is to provide an apparatus which performs correction only to a high-brightness portion generated in a particular region, in which a decrease in brightness is necessary, and glaze is removed or reduced. A correction process in which the brightness or the lightness is decreased is simply performed to a pixel in which the brightness or the lightness is high, but a predetermined region (for example, face, eyes, and mouth) of a subject is detected and a degree of correction of each pixel is determined based on the detection result (a position and a color of the predetermined region). Therefore, the region in which the decrease in brightness is not necessary is maintained at high brightness, and the image correction is performed only to the region in which the decrease in brightness is necessary (for example, the region in which the glaze of a skin is generated).

Claims

1. An image correction apparatus comprising:

a detection device configured to detect a predetermined region of a subject from an inputted image;

a domain determination device configured to determine a domain, where image correction is performed, based on a position of the detected predetermined region and brightness or lightness of each pixel of the inputted image; and

a correction device configured to perform image correction to the pixel included in the determined domain such that the brightness or the lightness of the pixel is decreased.

2. An image correction apparatus comprising:

a detection device configured to detect a predetermined region of a subject from an inputted image;

an intensity value computing device configured to compute an intensity value indicating how close a color component of the pixel is to a dominant color component of the detected predetermined region; and

a correction device configured to perform image correction to each pixel such that brightness or lightness of the pixel is decreased, wherein the correction device determines a degree of correction performed to each pixel based on the intensity value and the brightness or the lightness of each pixel of the inputted image.

3. An image correction apparatus according to claim 2, wherein the correction device weakens the degree of correction used to compute a color component close to the color component of the pixel of the inputted image, as the intensity value of the pixel indicates that the color component is farther away from the dominant color component of the predetermined region, and as the brightness or the lightness of the pixel has a lower value, wherein the color component close to the color component of the pixel becomes the color component of the pixel;

and

the correction device strengthens the degree of correction used to compute the color component, as the intensity value of the pixel indicates that the color component is closer to the dominant color component of the predetermined region, and as the brightness or the lightness of the pixel has a higher value, the color component in which the brightness or the lightness is decreased becomes the color component of the pixel.

4. An image correction apparatus according to claim 2, further comprising a blurring device which performs a blurring process to the inputted image,

wherein the correction device weakens the degree of correction used to compute the color component close to the color component of the pixel of the inputted image, as the intensity value of the pixel indicates that the color component is farther away from the dominant color component which of the predetermined region, and as the brightness or the lightness of the pixel has a lower value, the color component closer to the color component of the pixel becomes the color component of the pixel;

and

the correction device strengths the degree of correction to compute the color component close to the color component, as the intensity value in each pixel indicates that the color component is closer to the dominant color component of the predetermined region, and as the brightness or the lightness of the pixel has a higher value, the color component closer to the color component of the pixel becomes the color component of the pixel.

5. An image correction apparatus according to claim 4, wherein the blurring device performs the blurring process by using only the pixel having a value indicating that the intensity value is close to the dominant color component of the predetermined region.

14. An image correction apparatus as in any one of claims 2, 6, or 7, wherein the correction device obtains the degree of correction in each pixel as a numerical value, and performs the correction process based on the numerical value by performing a smoothing process to the numerical value to obtain the degree of correction for each pixel.

6. An image correction apparatus comprising:

a detection device configured to detect a predetermined region of a subject from an inputted image; and

a correction device configured to perform image correction to each pixel such that brightness or lightness of the pixel is decreased, wherein the correction device determines a degree of correction to be performed to each pixel based on a position of the detected predetermined region and the brightness or lightness of each pixel of the inputted image.

11. An image correction apparatus according to claims 6 or 7, wherein the correction device determines an estimated domain which includes a person'"'"'s face based on the position of the detected predetermine region, and performs the image correction to the pixels, included in the domain, based on the brightness or the lightness of each pixel.

12. An image correction apparatus according to claims 6 or 7, wherein the correction device determines an estimated domain where glaze is generated on the skin of a person'"'"'s face based on the position of the detected predetermined region, and performs the image correction to the pixels, included in the domain, based on the brightness or the lightness of each pixel.

13. An image correction apparatus according to claims 6 or 7, wherein the correction device estimates a position of eyes and/or mouth based on the position of the detected predetermined region, and performs the image correction to the pixels in the domain, except for the eyes and/or mouth, based on the brightness or the lightness of each pixel.

7. An image correction apparatus comprising:

a detection device configured to detect a predetermined region of a subject from an inputted image;

an intensity value computing device configured to compute an intensity value indicating how close a color component of the pixel is to a dominant color component of the detected predetermined region; and

a correction device configured to perform image correction to each pixel such that brightness or lightness of the pixel is decreased, wherein the correction device determines a degree of correction to be performed to each pixel based on a position of the detected predetermined region, the intensity value, and the brightness or the lightness of each pixel of the inputted image.

8. An image correction apparatus according to claim 7, wherein the correction device weakens the degree of correction used to compute a color component close to the color component of the pixel of the inputted image, as the intensity value of the pixel indicates that the color component is farther away from the dominant color component of the predetermined region, and as the brightness or the lightness of the pixel has a lower value, wherein the color component close to the color component of the pixel becomes the color component of the pixel;

and

the correction device strengthens the degree of correction used to compute the color component, as the intensity value of the pixel indicates that the color component is closer to the dominant color component of the predetermined region, and as the brightness or the lightness of the pixel has a higher value, the color component in which the brightness or the lightness is decreased becomes the color component of the pixel.

9. An image correction apparatus according to claim 7, further comprising a blurring device which performs a blurring process to the inputted image,

wherein the correction device weakens the degree of correction used to compute the color component close to the color component of the pixel of the inputted image, as the intensity value of the pixel indicates that the color component is farther away from the dominant color component which of the predetermined region, and as the brightness or the lightness of the pixel has a lower value, the color component closer to the color component of the pixel becomes the color component of the pixel;

and

the correction device strengths the degree of correction to compute the color component close to the color component, as the intensity value in each pixel indicates that the color component is closer to the dominant color component of the predetermined region, and as the brightness or the lightness of the pixel has a higher value, the color component closer to the color component of the pixel becomes the color component of the pixel.

10. An image correction apparatus according to claim 9, wherein the blurring device performs the blurring process by using only the pixel having a value indicating that the intensity value is close to the dominant color component of the predetermined region.

15. A program which causes an information processing apparatus to execute the steps of:

detecting a predetermined region of a subject from an inputted image;

determining a domain, where image correction is performed, based on a position of the detected predetermined region and brightness or lightness of each pixel of the inputted image; and

performing image correction to the pixels included in the determined domain such that the brightness or the lightness of the pixel is decreased.

16. A program which causes an information process apparatus to execute the steps of:

detecting a predetermined region of a subject from an inputted image;

computing an intensity value indicating how close a color component of the pixel is to a dominant color component of the detected predetermined region in each pixel; and

performing image correction to each pixel such that brightness or lightness of the pixel is decreased, the performing step determining a degree of correction to be performed to each pixel based on the intensity value and the brightness or the lightness of each pixel of the inputted image.

17. A program which causes an information processing apparatus to execute the steps of:

detecting a predetermined region of a subject from an inputted image;

performing image correction to each pixel such that brightness or lightness of the pixel is decreased, the image correction performing step determining a degree of correction performed to each pixel based on a position of the detected predetermine region, the intensity value, and the brightness or the lightness of each pixel of the inputted image.

18. A program which caused an information process apparatus to execute the steps of:

detecting a predetermined region of a subject from an inputted image;

computing an intensity value indicating how close a color component of the pixel is to a dominant color component of the detected predetermined region in each pixel; and

performing image correction to each pixel such that brightness or lightness of the pixel is decreased, the image correction performing step determining a degree of correction to be performed to each pixel based on a position of the detected predetermined region, the intensity value, and the brightness or the lightness of each pixel of the inputted image.

19. An image correction method comprising:

a step in which an information processing apparatus detects a predetermined region of a subject from an inputted image;

a step in which the information processing apparatus determines a domain, where image correction is performed, based on a position of the detected predetermined region and brightness or lightness of each pixel of the inputted image; and

a step in which the information processing apparatus performs image correction to the pixels included in the determined domain such that the brightness or the lightness of the pixels is decreased.

20. An image correction method comprising:

a step in which an information processing apparatus detects a predetermined region of a subject from an inputted image;

a step in which the information processing apparatus computes an intensity value indicating how close a color component of the pixel is to a dominant color component of the detected predetermined region; and

a step in which the information processing apparatus performs image correction to each pixel such that brightness or lightness of the pixel is decreased, wherein the information processing apparatus determines a degree of correction to be performed to each pixel based on the intensity value and the brightness or lightness of each pixel of the inputted image.

21. An image correction method comprising:

a step in which an information processing apparatus detects a predetermined region of a subject from an inputted image; and

a step in which the information processing apparatus performs image correction to each pixel such that brightness or lightness of the pixel is decreased, the image correction step in which the information processing apparatus determines a degree of correction to be performed to each pixel based on a detected position of the detected predetermined region and the brightness or the lightness of each pixel of the inputted image.

22. An image correction method comprising:

a step in which an information processing apparatus detects a predetermined region of a subject from an inputted image;

a step in which the information processing apparatus computes an intensity value indicating how close a color component of the pixel is to a dominant color component of the detected predetermined region; and

a step in which the information processing apparatus performs image correction to each pixel such that brightness or lightness is decreased, wherein the information processing apparatus determines a degree of correction performed to each pixel based on a position of the detected predetermined region, the intensity value, and the brightness or the lightness of each pixel of the inputted image.