Image compensation device, image processing apparatus and methods thereof

Patent metadata

Field	Value
Publication number	US-9270867-B2
Application number	US-201113334724-A
Country	US
Kind code	B2
Filing date	Dec 22, 2011
Priority date	Apr 18, 2011
Publication date	Feb 23, 2016
Grant date	Feb 23, 2016

Abstract

An image compensating apparatus includes an input unit to receive input of an photo image, a Gaussian filtering unit to perform Gaussian filtering on the photo image, a division-map generating unit to convert the photo image on which the Gaussian filtering is performed into a color space including a plurality of color components and then generating a chromaticity division-map based on a color coordinate value in the color space, a calculating unit to calculate average chromaticity of each respective region by using the chromaticity division-map, and a compensating unit to compensate chromaticity of each respective region of the photo image by using the average chromaticity of each respective region. Accordingly, a faded image input to the input unit may effectively be compensated.

First claim

What is claimed is:

1. An image compensating apparatus comprising:
an input unit to receive input of an photo image;
a Gaussian filtering unit to perform Gaussian filtering on the photo image;
a division-map generating unit to convert the photo image on which the Gaussian filtering is performed into a color space comprising a plurality of color components and then generating a chromaticity division-map for dividing the photo image on which the Gaussian filtering is performed into regions according to chromaticity based on a color coordinate value in the color space;
a calculating unit to calculate average chromaticity of each respective region among the regions by using the chromaticity division-map; and
a compensating unit to compensate chromaticity of each respective region of the photo image by using the average chromaticity of each respective region.

2. The image compensating apparatus of claim 1 , further comprising a converting unit to convert the photo image on which the Gaussian filtering is performed into a C-M-Y color space,
wherein the division-map generating unit converts the photo image on which Gaussian filtering is performed into an L-Cyb-Crg color space, and generates the chromaticity division-map based on a Cyb-Crg color coordinate value, and
wherein the compensating unit compensates the chromaticity by using a CMY value converted by the converting unit and the average chromaticity of each respective region.

3. The image compensating apparatus of claim 2 , wherein the compensating unit compensates the photo image by using a weight obtained by converting a size of each channel in a Cyb-Crg space into a CMY value.

4. The image compensating apparatus of claim 3 , wherein the division-map generating unit checks Cyb and Crg values of each pixel,
wherein, when the Cyb value is equal to or greater than a first predetermined threshold value, the division-map generating unit determines a corresponding pixel to yellow,
wherein, when the Cyb value is less than the first predetermined threshold value, the division-map generating unit determines the corresponding pixel to blue,
wherein, when the Crg value is equal to or greater than a second predetermined threshold value, the division-map generating unit determines the corresponding pixel to red, and
wherein, when the Crg value is less than the second predetermined threshold value, the division-map generating unit determines the corresponding pixel to green.

5. The image compensating apparatus of claim 3 , further comprising:
a saturation and contrast adjusting unit to adjust saturation and contrast of an image of which chromaticity is compensated by the compensating unit.

6. The image compensating apparatus of claim 2 , wherein the calculating unit calculates average chromaticity of each CMY value according to the following equation:

I

C
,
avg

⁡

(
n
)

=

1

NP
n

⁢

∑

x
=
0

NP
n

⁢
1

-

R
⁡

(

x
,
y
,
n

)

I

M
,
avg

⁡

(
n
)

=

1

NP
n

⁢

∑

x
=
0

NP

n
⁢

⁢
1

-

G
⁡

(

x
,
y
,
n

)

I

Y
,
avg

⁡

(
n
)

=

1

NP
n

⁢

∑

x
=
0

NP
n

⁢
1

-

B
⁡

(

x
,
y
,
n

)

wherein ‘NPn’ is the number of pixels of a region ‘n’, ‘n’ is each region, and R(x,y,n), G(x,y,n), and B(x,y,n) are R, G and B values of each pixel of the region ‘n’, respectively.

7. The image compensating apparatus of claim 6 , wherein the compensating unit compensates chromaticity of each respective region of the photo image according to the following equation:

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Assignees

• Kim Kyeong-Man
• Kim Hyun-Cheol
• Cho Min-Ki
• Oh Hyun-Soo
• Song Eun-Ah
• Ha Yeong-Ho
• Kim Dae-Chul
• Kyung Wang-Jun
• Samsung Electronics Co Ltd

Inventors

• Kim Kyeong-Man
• Kim Hyun-Cheol
• Cho Min-Ki
• Oh Hyun-Soo
• Song Eun-Ah
• Ha Yeong-Ho
• Kim Dae-Chul
• Kyung Wang-Jun

Classifications

• H04N9/64

  Circuits for processing colour signals (H04N9/77 takes precedence; camera processing pipelines for processing colour signals H04N23/84) · CPC title

• H04N1/00411

  the display also being used for user input, e.g. touch screen · CPC title

• H04N1/6027

  Correction or control of colour gradation or colour contrast (H04N1/6058 takes precedence) · CPC title

• H04N1/6008

  with primary colour signals, e.g. RGB or CMY(K) · CPC title

• H04N1/6005 Primary

  with luminance or chrominance signals, e.g. LC1C2, HSL or YUV · CPC title