METHOD AND APPARATUS FOR ADJUSTING BRIGHTNESS OF INPUT IMAGE

1 . A method of adjusting a brightness of an input image, the method comprising:

performing brightness conversion on a brightness component value of the input image; and

compensating a chroma value of the input image based on input image information and a brightness value obtained from the brightness conversion, wherein the input image information includes a chroma component value and the brightness component value of the input image.

2 . The method of claim 1 , wherein a color space in which the brightness conversion is performed is a device dependent color space.

3 . The method of claim 2 , wherein the device dependent color space is one of a YCbCr color space, a Hue, Saturation, Value (HSV) color space, and a Hue, Saturation, Intensity (HSI) color space.

4 . The method of claim 1 , wherein when the brightness conversion is performed in a YCbCr color space, a Y component is the brightness component and Cb and Cr components are the chroma component.

5 . The method of claim 1 , wherein the performing and the compensating are performed in a device dependent color space, and

wherein a brightness component value and a chroma component value of the input image in a device independent color space are substantially the same as values obtained by converting, in the device independent color space, a brightness component value that is output after performing the brightness conversion and a chroma component value that is output after compensating the chroma value of the input image.

6 . The method of claim 1 , wherein the brightness conversion is performed by using at least one from among a predetermined parameter, characteristics of an imaging apparatus for performing the brightness conversion, and an input signal received from an external source.

7 . The method of claim 1 , wherein the brightness conversion and the chroma compensation are performed for each pixel of the input image.

8 . The method of claim 1 , further comprising, when the input image is an RGB image, performing a color space conversion on the RGB image and splitting the input image into the brightness component and the chroma component.

9 . The method of claim 1 , wherein the input image information further includes a hue component value of the input image.

10 . An apparatus for adjusting a brightness of an input image, the apparatus comprising:

a brightness conversion unit configured to perform brightness conversion on a brightness component value of the input image; and

a chroma compensation unit configured to compensate a chroma value of the input image based on input image information and a brightness value obtained from the brightness conversion, wherein the input image information includes a chroma component value and the brightness component value of the input image.

11 . The apparatus of claim 10 , wherein a color space in which the brightness conversion is performed is a device dependent color space.

12 . The apparatus of claim 11 , wherein the device dependent color space is one of a YCbCr color space, a Hue, Saturation, Value (HSV) color space, and a Hue, Saturation, Intensity (HSI) color space.

13 . The apparatus of claim 10 , wherein when the brightness conversion is performed in a YCbCr color space, a Y component is the brightness component and Cb and Cr components are the chroma component.

14 . The apparatus of claim 10 , wherein the brightness conversion and chroma compensation are performed in a device dependent color space, and

wherein a brightness component value and a chroma component value of the input image in a device independent color space are substantially the same as values obtained by converting, in the device independent color space, a brightness component value that is output after the brightness conversion and a chroma component value that is output after the chroma compensation.

15 . The apparatus of claim 10 , wherein the brightness conversion is performed by using at least one from among a predetermined parameter, characteristics of an imaging apparatus for performing the brightness conversion, and an input signal received from an external source.

16 . The apparatus of claim 10 , wherein the brightness conversion and the chroma compensation are performed for each pixel of the input image.

17 . The apparatus of claim 10 , further comprising a first color space conversion unit that when the input image is an RGB image, performs a color space conversion on the RGB image and splits the input image into the brightness component and the chroma component.

18 . The apparatus of claim 10 , wherein the input image information further includes a hue component value of the input image.

19 . A digital display device comprising the apparatus of claim 10 .

20 . A computer-readable recording medium having recorded thereon a program for executing the method of claim 1 .

21 . An apparatus for adjusting a brightness of an input image, the apparatus comprising:

a brightness conversion unit configured to perform brightness conversion on a brightness component value of the input image; and

a chroma compensation unit configured to predict a variation in a chroma component of the input image occurring during the brightness conversion based on a variation in the brightness component value of the input image and compensate the chroma component of the input image based on the predicted variation.

22 . The apparatus of claim 21 , wherein the chroma compensation unit compensates the chroma component of the input image by adding the predicted variation to the chroma component of the input image.