A method and apparatus for adjusting a color of an image, the apparatus includes a unit setting at least one adjustment region shaped as an ellipse in a color space; and a unit converting colors of pixels included in the adjustment region to other colors based on a variable set.
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What is claimed is: 1. A method of adjusting colors of an image, comprising: setting more than one adjustment regions shaped as an ellipse in a color space; and converting colors of pixels included in each adjustment region to other colors based on a variable set, wherein a coordinate point of a re
What is claimed is: 1. A method of adjusting colors of an image, comprising: setting more than one adjustment regions shaped as an ellipse in a color space; and converting colors of pixels included in each adjustment region to other colors based on a variable set, wherein a coordinate point of a reference color is set to a centroid point of the ellipse, including a coordinate point of a target color into which the reference color has to be converted, wherein a color coordinate point of a current pixel is converted into an adjusted color coordinate point using a conversion coefficient determined based on the coordinate point of the target color, the centroid point of the ellipse and a boundary of the ellipse, and wherein the converting of the colors of the pixels included in each adjustment region comprises changing color coordinates of a current pixel for each adjustment region in pixel units: determining whether a color of each pixel is included in each adjustment region using the changed color coordinates of the current pixel; calculating the conversion coefficient of the current pixel with respect to each adjustment region including the current pixel; and converting the color coordinate point of the pixel using the conversion coefficient in each adjustment region including the current pixel. 2. The method of claim 1, wherein the setting of each adjustment region comprises: setting the coordinate point of the reference color, the coordinate point of the target color into which the reference color is converted, lengths of a long-axis and a short-axis of the ellipse, and a rotation angle of the ellipse; and setting the ellipse having the coordinate point of the reference color as a centroid and including the coordinate point of the target color, to each adjustment region, the ellipse being formed by the lengths of the long-axis and the short-axis and the rotation angle of the ellipse and including the coordinate point of the target color. 3. The method of claim 2, wherein the setting of each adjustment region further comprises: determining first and second variables obtained from the rotation angle of the ellipse and third and fourth variables obtained from the lengths of the long-axis and the short-axis of the ellipse, the coordinate point of the reference color and the coordinate point of the target color as the variable set for each adjustment region. 4. The method of claim 3, wherein the first, second, third and fourth variables are calculated using the following equation: m1=cos(−θ) m2 =sin(−θ) f = 1 a 2 g = 1 b 2 wherein m1 indicates the first variable, m2 indicates the second variable, f indicates the third variable, g indicates the fourth variable, a indicates the length of the long-axis of the ellipse, b indicates the length of the short-axis of the ellipse, and θ indicates the rotation angle of the ellipse. 5. The method of claim 1, wherein the variable set is determined for each adjustment region and the variable sets are stored as a lookup table. 6. The method of claim 1, wherein the changing of color coordinates of the current pixel is performed using the following equation: [ p 1 x p 1 y ] = ( m 1 - m 2 m 2 m 1 ) ( x - x r y - y r ) = ( m 1 ( x - x r ) - m 2 ( y - y r ) m 2 ( x - x r ) + m 1 ( y - y r ) ) wherein m1=cos(−θ), and m2=sin(−θ) when a and b indicate lengths of a long-axis and a short-axis of an ellipse corresponding to a predetermined adjustment region, θ indicates a rotation angle of the ellipse, (plx, ply) indicates a changed color coordinate point, (x, y) indicates a color coordinate point of an input pixel, and (xr, yr) indicates a coordinate point of a reference color. 7. The method of claim 1, wherein the determining of whether the color of each pixel is included in each adjustment region is performed using the following equation: f×plx2+g×ply2≦1 wherein f=1/a2, and g=1/b2 when a and b indicate lengths of a long-axis and a short-axis of an ellipse corresponding to a predetermined adjustment region, θ indicates a rotation angle of the ellipse, and (plx, ply) indicates a changed color coordinate point. 8. The method of claim 1, wherein the calculating of the conversion coefficient is performed using the following equations: B = p 1 y p 1 x r = x c 2 + y c 2 = 1 + B 2 f + gB 2 α = r - P - R r = r - ( x - x r ) 2 + ( y - y r ) 2 r wherein B indicates a slope of a straight line y=Bx connecting a color coordinate point P(x, y) of the current pixel and the centroid point of an ellipse, r indicates a distance between coordinates (xr, yr) of a reference color R and an outline boundary of an adjustment region on a line passing through the color coordinate point P(x, y) of an input pixel P, (xc, yc) indicates a coordinate point of an intersection point between the straight line y=Bx and the outline boundary of the adjustment region, α indicates a conversion coefficient and f=1/a2, and g=1/b2 when a and b indicate lengths of a long-axis and a short-axis of the ellipse. 9. The method of claim 8, wherein the distance r is calculated as r=1/g when plx2=0 and the distance r is calculated as r=1/f when ply2=0. 10. The method of claim 1, wherein the converting of the color coordinate is performed using the following equation: [ x ′ y ′ ] = [ x y ] + α [ x r ′ - x r y r ′ - y r ] wherein (x′, y′) indicates a color coordinate point obtained as a color adjustment result, (x, y) indicates a color coordinate point of the current pixel, α indicates a conversion coefficient, (xr, yr) indicates reference color coordinates, and (xr′, yr′) indicates target color coordinates. 11. The method of claim 10, wherein the adjusted color coordinates (x′, y′) is set to the target color coordinates (xr′, yr′) when the color coordinate point P(x, y) of the current pixel matches the reference color coordinate point R(xr, yr). 12. The method of claim 1, wherein priorities are allocated for each adjustment region. 13. The method of claim 12, wherein the converting of the colors of the pixels further comprises if the current pixel is included in more than one adjustment region, converting the color coordinate point of the current pixel by a conversion coefficient calculated for the current pixel in an adjustment region having a highest priority. 14. The method of claim 1, wherein weights are allocated for each adjustment region. 15. The method of claim 14, wherein the converting of the colors of the pixels further comprises if the current pixel is included in more than one adjustment region, the color coordinate point of the current pixel is converted for each adjustment region using a conversion coefficient calculated for the current pixel, the weights are multiplied by the converted color coordinate points, and a vector sum operation is performed. 16. A non-transitory computer readable medium having recorded thereon a computer readable program for performing a method of adjusting colors of an image, the method comprising: setting more than one adjustment region shaped as an ellipse in a color space; and converting colors of pixels included in each adjustment region to other colors based on a variable set, wherein a coordinate point of a reference color is set to a centroid point of the ellipse, including a coordinate point of a target color into which the reference color has to be converted, wherein a color coordinate point of a current pixel is converted into an adjusted color coordinate point using a conversion coefficient determined based on the coordinate point of the target color, the centroid point of the ellipse and a boundary of the ellipse, and wherein the converting of the colors of the pixels included in each adjustment region comprises changing color coordinates of a current pixel for each adjustment region in pixel units; determining whether a color of each pixel is included in each adjustment region using the changed color coordinates of the current pixel; calculating the conversion coefficient of the current pixel with respect to each adjustment region including the current pixel; and converting the color coordinate point of the pixel using the conversion coefficient in each adjustment region including the current pixel. 17. An apparatus for adjusting colors of an image, comprising: an adjustment unit setting more than one adjustment region shaped as an ellipse in a color space; and a color converter unit converting colors of pixels included in each adjustment region to other colors based on a variable set, wherein a coordinate point of a reference color is set to a centroid point of the ellipse, including a coordinate point of a target color into which the reference color has to be converted, wherein a color coordinate point of a current pixel is converted into an adjusted color coordinate point using a conversion coefficient determined based on the coordinate point of the target color, the centroid point of the ellipse and a boundary of the ellipse, and wherein the color converter unit comprises an adjustment region information storage unit storing a variable set including a plurality of variables obtained from the lengths of the long-axis and the short-axis of the ellipse, and the rotation angle of the ellipse, the reference color coordinate point, and the target color coordinate point, for each of the adjustment regions; an adjustment object determinator determining whether a current pixel is a pixel to be adjusted by judging whether the current pixel is included in each adjustment region; and a color adjustment unit performing the color adjustment based on a color coordinate point of the current pixel and the variable set of the corresponding adjustment region if determined that the current pixel is included in each adjustment region. 18. The apparatus of claim 17, wherein in the adjustment unit, each adjustment region is set further using lengths of a long-axis and a short-axis of the ellipse, and a rotation angle of the ellipse. 19. The apparatus of claim 17, wherein the color converter unit calculates the conversion coefficient of the current pixel with respect to an adjustment region including the current pixel and converts the color coordinate point of the current pixel into the adjusted color coordinate point using the calculated conversion coefficient. 20. The apparatus of claim 17, wherein in the adjustment unit, priorities are allocated for each of the adjustment regions. 21. The apparatus of claim 20, wherein the color converter unit converts the color coordinate point of a current pixel by the conversion coefficient calculated for the current pixel in an adjustment region having a highest priority, if the current pixel is included in more than one adjustment region. 22. The apparatus of claim 17, wherein weights are allocated for each adjustment region. 23. The apparatus of claim 22, wherein the color coordinate point of a current pixel is converted for each adjustment region using the conversion coefficient calculated for the current pixel obtaining converted color coordinate points, the weights are multiplied by the converted color coordinate points, and a vector sum operation is performed, if the current pixel is included in more than one adjustment region. 24. The apparatus of claim 17, wherein the adjustment unit sets an adjustment region based on information input by a user through a user interface. 25. The apparatus of claim 17, wherein the color adjustment unit includes a switching unit, a conversion coefficient calculator and a coordinate converter. 26. The apparatus of claim 25, wherein the switching unit receives an adjustment object determination result from the adjustment object determinator and provides the current pixel to the conversion coefficient calculator. 27. The apparatus of claim 26, wherein the switching unit allows the current pixel to be color-adjusted if determined that the current pixel is a pixel to be adjusted. 28. The apparatus of claim 26, wherein the switching unit prevents the current pixel from being color-adjusted if determined that the current pixel is not a pixel to be adjusted. 29. The apparatus of claim 25, wherein the conversion coefficient calculator calculates the conversion coefficient of the current pixel in a relevant adjustment region in accordance with the variable set of each adjustment region provided by the adjustment region information storage unit. 30. The apparatus of claim 29, wherein the coordinate converter receives the conversion coefficient of the current pixel in the relevant adjustment region calculated by the conversion coefficient calculator and the variable set of the relevant adjustment region and adjusts a color of the current pixel by converting a first color coordinate point of the current pixel into a second color coordinate point.
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