1. A method of segmenting an object in an image, the method comprising: obtaining a first image including the object; receiving an input signal on the first image; obtaining position information based on the received input signal; selecting, by a processor, at least one pixel included in the first image, based on the position information; generating, by the processor, a second image by dividing the first image into several areas, using the selected at least one pixel; and segmenting, by the processor, the object in the first image by using the first image and the second image.