Method and apparatus for generating reconstructed block

A reconstructed block creating method comprising:

• decoding an intra prediction mode of a current block using an intra prediction mode group indicator, a prediction mode index and a MPM group, wherein the MPM group is generated using intra prediction modes of left and top blocks of the current block, and includes three intra prediction modes;
• constructing a prediction block using the intra prediction mode;
• inversely quantizing a received residual signal using a quantization parameter to create an inversely quantized block and inversely transforming the inversely quantized block to create a residual block;
• and
• adding the prediction block and the residual block to create a reconstructed block,
• wherein the quantization parameter is reconstructed using received information indicating a minimum quantization coding unit (CU) size and the information indicating the minimum quantization CU size is determined by a parameter transmitted from a picture parameter set,
• wherein the intra prediction mode of the current block is set equal to an intra prediction mode indicated by the prediction mode index in the MPM group when the intra prediction mode group indicator indicates the MPM group, and the intra prediction mode of the current block is determined out of intra prediction modes other than the three intra prediction modes in the MPM group using the three intra prediction modes in the MPM group and the prediction mode index when the intra prediction mode group indicator does not indicate the MPM group, and
• wherein when the intra prediction modes of the left and top blocks are not equal to each other and non-directional intra prediction modes, the MPM group includes the intra prediction modes of the left and top blocks and a vertical mode.