METHOD AND DEVICE FOR ENCODING INTRA PREDICTION MODE FOR IMAGE PREDICTION UNIT, AND METHOD AND DEVICE FOR DECODING INTRA PREDICTION MODE FOR IMAGE PREDICTION UNIT

摘要

An apparatus for decoding an intra prediction mode of an image, the apparatus comprising: 5 an intra prediction obtainer that obtains intra prediction mode information regarding a prediction unit of a luma component, if the intra prediction mode regarding the prediction unit of the luma component is one of a planar mode, a DC mode, a horizontal mode and a vertical mode, wherein the intra prediction mode candidate group of the chroma component includes a diagonal mode, obtains an intra prediction mode candidate group o of a chroma component, obtains intra prediction mode information regarding a prediction unit of the chroma component, and determines the intra prediction mode regarding the prediction unit of the chroma component from among a plurality of intra prediction modes which are included in the intra prediction mode group of the chroma component based on the obtained intra prediction mode information regarding the prediction unit of the 5 chroma component ; and an intra prediction performer that performs intra prediction on the prediction unit of the chroma component according to the determined intra prediction mode, wherein an intra prediction mode candidate group of the luma component includes the planar mode, the DC mode and an intra prediction mode indicating a particular .o direction among a plurality of directions, and the particular direction is indicated by using one of a dx number in a horizontal direction and a fixed number in a vertical direction, or a dy number in the vertical direction and a fixed number in the horizontal direction, wherein dx and dy are integers.