A method of constructing a merge candidate list for video coding, comprising: constructing a merge candidate list using available spatial and temporal merge candidates, and deriving motion information using a merge index and the merge candidate list; generating a prediction block using the motion information; generating a quantization block by inverse-scanning quantized coefficient components according to a diagonal scan, inverse-quantizing the quantization block using a quantization parameter and a quantization matrix, and inverse transforming the inversely-quantized quantization block to generate a residual block; and deriving a reconstructed block using the prediction block and the residual block, wherein the spatial merge candidates are motion information of spatial merge candidate blocks, and the spatial merge candidate blocks are a left block, an above block, an above-right block, a left-below block or an above-left block of the current block, wherein the spatial merge candidate corresponding to a first prediction unit partitioned by asymmetric partitioning is set as unavailable if a current prediction unit is a second prediction unit partitioned by the asymmetric partitioning, wherein if the size of the current prediction unit is (3/2)Nx2N, the left spatial merge candidate is set as unavailable, wherein a motion vector of the temporal merge candidate is a motion vector of a temporal merge candidate block within a temporal merge candidate picture, wherein the quantization parameter is generated using a differential quantization parameter and a quantization parameter predictor, wherein the quantization parameter predictor is generated using an average of a left quantization parameter and an above quantization parameter when both of the left quantization parameter and the above quantization parameter are available, and wherein the previous quantization parameter is set as the quantization parameter predictor when both of the left quantization parameter and the above quantization parameter are not available. constructing a merge candidate list using available spatial and temporal merge candidates, and deriving motion information using a merge index and the merge candidate list; generating a prediction block using the motion information; generating a quantization block by inverse-scanning quantized coefficient components according to a diagonal scan, inverse-quantizing the quantization block using a quantization parameter and a quantization matrix, and inverse transforming the inversely-quantized quantization block to generate a residual block; and deriving a reconstructed block using the prediction block and the residual block, wherein the spatial merge candidates are motion information of spatial merge candidate blocks, and the spatial merge candidate blocks are a left block, an above block, an above-right block, a left-below block or an above-left block of the current block, wherein the spatial merge candidate corresponding to a first prediction unit partitioned by asymmetric partitioning is set as unavailable if a current prediction unit is a second prediction unit partitioned by the asymmetric partitioning, wherein if the size of the current prediction unit is (3/2)Nx2N, the left spatial merge candidate is set as unavailable, wherein a motion vector of the temporal merge candidate is a motion vector of a temporal merge candidate block within a temporal merge candidate picture, wherein the quantization parameter is generated using a differential quantization parameter and a quantization parameter predictor, wherein the quantization parameter predictor is generated using an average of a left quantization parameter and an above quantization parameter when both of the left quantization parameter and the above quantization parameter are available, and wherein the previous quantization parameter is set as the quantization parameter predictor when both of the left quantization parameter and the above quantization parameter are not available.