1. An apparatus for improving quality of an enlarged image, comprising: a first image input unit and a second image input unit configured to output a first image and a second image, respectively, which are obtained by capturing a same subject from different positions, spaced apart by a predetermined gap; a first image processor configured to convert a resolution of the first image to a first resolution; a display configured to display the first image outputted from the first image processor; a second image processor configured to: convert a resolution of the second image to a second resolution set higher than the first resolution; when a first area to be enlarged in the displayed the first image is selected, determine a second area corresponding to the first area in the second image using a parallax between the first image converted to the first resolution and the second image converted to the second resolution and a resolution difference between the second resolution and the first resolution; and crop an image corresponding to the second area from the second image; and a controller configured to control the display to display the cropped image on the first image in an overlaying manner.