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.