Patent ID: 8270486

Claim:
A method of decoding an image, the method comprising: extracting from a bitstream information that indicates an intra prediction mode applied to a current block to be decoded; and performing intra prediction on the current block according to the intra prediction mode indicated by the extracted information, wherein the intra prediction mode indicates the intra prediction for a current pixel located at a position (i,j) of the current block, where i and j are integers, the intra prediction comprising: determining one of (i) a left neighboring pixel of a first previous block adjacent to a left side of the current block and decoded prior to the current block and (ii) an up neighboring pixel of a second previous block adjacent to an upper side of the current block and decoded prior to the current block, the left neighboring pixel determined based on a shift operation as division by power of 2, j*dy>>n and the up neighboring pixel determined based on a shift operation as division by power of 2, i*dx>>m, where dx, dy, m, and n are integers; and performing the intra prediction using the determined one of the left neighboring pixel and the up neighboring pixel, wherein the current block is obtained by hierarchically splitting a maximum coding unit that is a coding unit having a maximum size based on depth information, and wherein the depth information indicates a number of times the maximum coding unit is split.