An apparatus for decoding video data, the apparatus comprising: a receiver configured to receive a bitstream comprising encoded video data; a parser configured to obtain, from the bitstream, information about a maximum size of a coding unit, split information of a coding unit, and information on a relationship between a depth of a coding unit and a quantization mode, wherein the information on said relationship indicates a quantization mode, for each depth among a plurality of depths, that indicates whether a quantization parameter delta of the respective depth is to be used; and a decoder configured to perform inverse-quantization and inverse-transformation, wherein: an image, corresponding to the encoded video data, is split into a plurality of maximum coding units using the information about a maximum size of a coding unit, a maximum coding unit, among the plurality of maximum coding units, is hierarchically split into the one or more coding units of depths including at least one of a current depth and a lower depth according to the split information, wherein for a coding unit of the current depth: the parser further determines whether the quantization parameter delta is to be used in the coding unit of the current depth, based on the information on said relationship; when the split information of the coding unit of the current depth indicates a split, the coding unit of the current depth is split into four coding units of the lower depth, independently from neighboring coding units, and when the split information of the coding unit of the current depth indicates a non-split, transformation units are obtained from the coding unit of the current depth, and the decoder performs inverse-quantization on the transformation units using the result of the determination of whether the quantization parameter delta is to be used in the coding unit of the current depth, and performs inverse-transformation on the transformation units. a receiver configured to receive a bitstream comprising encoded video data; a parser configured to obtain, from the bitstream, information about a maximum size of a coding unit, split information of a coding unit, and information on a relationship between a depth of a coding unit and a quantization mode, wherein the information on said relationship indicates a quantization mode, for each depth among a plurality of depths, that indicates whether a quantization parameter delta of the respective depth is to be used; and a decoder configured to perform inverse-quantization and inverse-transformation, wherein: an image, corresponding to the encoded video data, is split into a plurality of maximum coding units using the information about a maximum size of a coding unit, a maximum coding unit, among the plurality of maximum coding units, is hierarchically split into the one or more coding units of depths including at least one of a current depth and a lower depth according to the split information, an image, corresponding to the encoded video data, is split into a plurality of maximum coding units using the information about a maximum size of a coding unit, a maximum coding unit, among the plurality of maximum coding units, is hierarchically split into the one or more coding units of depths including at least one of a current depth and a lower depth according to the split information, wherein for a coding unit of the current depth: the parser further determines whether the quantization parameter delta is to be used in the coding unit of the current depth, based on the information on said relationship; when the split information of the coding unit of the current depth indicates a split, the coding unit of the current depth is split into four coding units of the lower depth, independently from neighboring coding units, and when the split information of the coding unit of the current depth indicates a non-split, transformation units are obtained from the coding unit of the current depth, and the decoder performs inverse-quantization on the transformation units using the result of the determination of whether the quantization parameter delta is to be used in the coding unit of the current depth, and performs inverse-transformation on the transformation units. the parser further determines whether the quantization parameter delta is to be used in the coding unit of the current depth, based on the information on said relationship; when the split information of the coding unit of the current depth indicates a split, the coding unit of the current depth is split into four coding units of the lower depth, independently from neighboring coding units, and when the split information of the coding unit of the current depth indicates a non-split, transformation units are obtained from the coding unit of the current depth, and the decoder performs inverse-quantization on the transformation units using the result of the determination of whether the quantization parameter delta is to be used in the coding unit of the current depth, and performs inverse-transformation on the transformation units.