Patent ID: 8619858

Claim:
A method of determining an intra prediction mode of a coding unit of a current picture, the method comprising: splitting a luminance component of the current picture into at least one luminance component coding unit based on a maximum coding unit that is a coding unit in which the current picture is encoded having a maximum size, and a depth that indicates hierarchical split information of the maximum coding unit; determining an intra prediction mode of the at least one luminance component coding unit; comparing costs of applying to a chrominance component coding unit candidate intra prediction modes of the chrominance component coding unit and the intra prediction mode of the at least one luminance component coding unit; and determining an intra prediction mode of the chrominance component coding unit from among the candidate prediction modes of the chrominance component coding unit and the determined intra prediction mode of the at least one luminance component coding unit having a minimum cost, based on a result of the comparing, wherein the intra prediction is performed by using an extension line having an angle of tan âˆ’1 (dy/dx) based on a pixel in the luminance component coding unit, wherein dx and dy are integers.