A method of intra prediction decoding an image, the method characterized by comprising: dividing a current picture of the image into at least one block having a predetermined size; extracting intra prediction mode of a current block from a bitstream, the intra prediction mode indicating a particular direction among a plurality of directions, the particular direction being indicated by i) dx number in a horizontal direction and a fixed number in a vertical direction, or ii) dy number in the vertical direction and the fixed number in the horizontal direction; and performing intra prediction on the current block according to the intra prediction mode, wherein the performing intra prediction comprising: determining location of neighboring pixels of the neighboring block previously reconstructed before the current block using shift operation based on a position of a current pixel and one of the dx number and the dy number indicating the particular direction, the neighboring pixels being located on a left side of the current block or an upper side of the current block, wherein: the location of the neighboring pixels located on the upper side of the current block is determined based on i * dx >> 5, where i is a position of the current pixel in the vertical direction, and dx is the dx number in the horizontal direction and >> is the bitwise shift operation, and the location of the neighboring pixels located on the left side of the current block is determined based on j * dy >> 5, where j is a position of the current pixel in the horizontal direction, and dy is the dy number in the vertical direction, wherein i) the fixed number in the vertical direction has a fixed value of 2^5 and the dx number is determined from among {32, 26, 21, 17, 13, 9, 5, 2, 0, -2, -5, -9, -13, -17, -21, -26, -32}, or ii) the fixed number in the horizontal direction has a fixed value of 2^5 and the dy number is determined from among {32, 26, 21, 17, 13, 9, 5, 2, 0, -2, -5, -9, -13, -17, -21, -26, -32} according to the intra prediction mode of the current block. dividing a current picture of the image into at least one block having a predetermined size; extracting intra prediction mode of a current block from a bitstream, the intra prediction mode indicating a particular direction among a plurality of directions, the particular direction being indicated by i) dx number in a horizontal direction and a fixed number in a vertical direction, or ii) dy number in the vertical direction and the fixed number in the horizontal direction; and performing intra prediction on the current block according to the intra prediction mode, wherein the performing intra prediction comprising: determining location of neighboring pixels of the neighboring block previously reconstructed before the current block using shift operation based on a position of a current pixel and one of the dx number and the dy number indicating the particular direction, the neighboring pixels being located on a left side of the current block or an upper side of the current block, determining location of neighboring pixels of the neighboring block previously reconstructed before the current block using shift operation based on a position of a current pixel and one of the dx number and the dy number indicating the particular direction, the neighboring pixels being located on a left side of the current block or an upper side of the current block, wherein: the location of the neighboring pixels located on the upper side of the current block is determined based on i * dx >> 5, where i is a position of the current pixel in the vertical direction, and dx is the dx number in the horizontal direction and >> is the bitwise shift operation, and the location of the neighboring pixels located on the left side of the current block is determined based on j * dy >> 5, where j is a position of the current pixel in the horizontal direction, and dy is the dy number in the vertical direction, the location of the neighboring pixels located on the upper side of the current block is determined based on i * dx >> 5, where i is a position of the current pixel in the vertical direction, and dx is the dx number in the horizontal direction and >> is the bitwise shift operation, and the location of the neighboring pixels located on the left side of the current block is determined based on j * dy >> 5, where j is a position of the current pixel in the horizontal direction, and dy is the dy number in the vertical direction, wherein i) the fixed number in the vertical direction has a fixed value of 2^5 and the dx number is determined from among {32, 26, 21, 17, 13, 9, 5, 2, 0, -2, -5, -9, -13, -17, -21, -26, -32}, or ii) the fixed number in the horizontal direction has a fixed value of 2^5 and the dy number is determined from among {32, 26, 21, 17, 13, 9, 5, 2, 0, -2, -5, -9, -13, -17, -21, -26, -32} according to the intra prediction mode of the current block. ii) the fixed number in the horizontal direction has a fixed value of 2^5 and the dy number is determined from among {32, 26, 21, 17, 13, 9, 5, 2, 0, -2, -5, -9, -13, -17, -21, -26, -32} according to the intra prediction mode of the current block.