A method of decoding video data, the method comprising: receiving a bitstream comprising encoded video data; and obtaining, 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; 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, further comprising, for a coding unit of the current depth: determining 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, inverse-quantization is performed 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 inverse-transformation is performed the transformation units. receiving a bitstream comprising encoded video data; and obtaining, 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; 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, further comprising, for a coding unit of the current depth: determining 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, inverse-quantization is performed 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 inverse-transformation is performed the transformation units. 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, further comprising, for a coding unit of the current depth: determining 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, inverse-quantization is performed 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 inverse-transformation is performed the transformation units. determining 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, inverse-quantization is performed 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 inverse-transformation is performed the transformation units.