An electronic apparatus includes: a storage and a processor. The processor is configured to: select a second pixel having a similarity to a first pixel equal to or greater than a threshold value among neighboring pixels based on a first chrominance signal of the first pixel and second chrominance signals of pixels neighboring the first pixel among a plurality of pixels included in an input image, identify index information corresponding to a pixel combination having a highest similarity to the first pixel based on a first luminance signal of the first pixel, a second luminance signal of the second pixel, and a plurality of pixel combinations with respect to the first pixel, and control the electronic apparatus to store the image by replacing a pixel value of the first pixel with the identified index information.