1. A method of displaying an image signal in a display apparatus, the display apparatus including a plurality of pixels each having at least two sub-pixels, the method comprising: (a) detecting pixels that belong to an edge of an input image; (b) changing pixel values of the sub-pixels constituting the pixels belonging to the edge; and (c) driving a display in accordance with the new pixel values, wherein (b) includes (b1) decreasing the right sub-pixel component among the sub-pixels in a single pixel if the edge belongs to the falling edge; and (b2) decreasing the left sub-pixel component among the sub-pixels in a single pixel if the edge belongs to the rising edge, wherein the decreased right sub-pixel component in (b1) is obtained based on the right sub-pixel component in the current pixel and the right sub-pixel component in the next pixel, and the decreased left sub-pixel component in (b2) is obtained based on the left sub-pixel component in the current pixel and the left sub-pixel component in the previous pixel, wherein the right sub-pixel component (R′) in (b1) is obtained by an equation 
 R′=α×{R ( p )− R ( p+ 1)}+ R ( p+ 1) wherein R(p) and R(p+1) respectively represent the right sub-pixel component in the current pixel and the right sub-pixel component in the next pixel, and α is a constant between 0 and 1, and wherein the edge is where a difference between a pixel value of a pixel and a pixel value of a previous or next pixel exceeds a predetermined threshold value.