An apparatus for decoding a video, the apparatus comprising: a processor which is configured for: determining at least one coding unit included in a maximum coding unit by using split information indicating whether a coding unit is split into smaller coding units, when information about a partition type indicates a symmetric partition type for a coding unit among the at least one coding unit, determining partitions by splitting at least one of a height and a width of the coding unit according to a symmetric ratio, when the information about a partition type indicates an asymmetric partition type for the coding unit among the at least one coding unit, determining partitions by splitting one of a height and a width of the coding unit according to an asymmetric ratio, and performing motion compensation using the partitions for the coding unit, characterized in that: the information about a partition type indicates whether a partition type is the symmetric partition type or the asymmetric partition type, the maximum coding unit is hierarchically split into the at least one coding unit of depths according to the split information parsed from a received bitstream, a coding unit of a current depth is one of rectangular data units split from a coding unit of an upper depth among the at least one coding unit of depths, when the split information indicates a split of the coding unit of the current depth, the coding unit of the current depth is split into coding units of a lower depth, independently from neighboring coding units, and when the split information indicates a non-split of the coding unit of the current depth, at least one prediction unit is obtained from the coding unit of the current depth, wherein the at least one prediction unit is one of the partitions, and at least one transformation unit for performing transformation is obtained from the coding unit of the current depth. determining at least one coding unit included in a maximum coding unit by using split information indicating whether a coding unit is split into smaller coding units, when information about a partition type indicates a symmetric partition type for a coding unit among the at least one coding unit, determining partitions by splitting at least one of a height and a width of the coding unit according to a symmetric ratio, when the information about a partition type indicates an asymmetric partition type for the coding unit among the at least one coding unit, determining partitions by splitting one of a height and a width of the coding unit according to an asymmetric ratio, and performing motion compensation using the partitions for the coding unit, characterized in that: the information about a partition type indicates whether a partition type is the symmetric partition type or the asymmetric partition type, the maximum coding unit is hierarchically split into the at least one coding unit of depths according to the split information parsed from a received bitstream, a coding unit of a current depth is one of rectangular data units split from a coding unit of an upper depth among the at least one coding unit of depths, when the split information indicates a split of the coding unit of the current depth, the coding unit of the current depth is split into coding units of a lower depth, independently from neighboring coding units, and when the split information indicates a non-split of the coding unit of the current depth, at least one prediction unit is obtained from the coding unit of the current depth, wherein the at least one prediction unit is one of the partitions, and at least one transformation unit for performing transformation is obtained from the coding unit of the current depth. the information about a partition type indicates whether a partition type is the symmetric partition type or the asymmetric partition type, the maximum coding unit is hierarchically split into the at least one coding unit of depths according to the split information parsed from a received bitstream, a coding unit of a current depth is one of rectangular data units split from a coding unit of an upper depth among the at least one coding unit of depths, when the split information indicates a split of the coding unit of the current depth, the coding unit of the current depth is split into coding units of a lower depth, independently from neighboring coding units, and when the split information indicates a non-split of the coding unit of the current depth, at least one prediction unit is obtained from the coding unit of the current depth, wherein the at least one prediction unit is one of the partitions, and at least one transformation unit for performing transformation is obtained from the coding unit of the current depth.