Video encoding method and apparatus and video decoding method and apparatus, based on hierarchical coded block pattern information

An apparatus for decoding video, the apparatus comprising:

• a receiver which receives a bitstream of encoded video;
• an obtainer which obtains, from the bitstream, encoded image data of a chroma component of a transformation unit included in a maximum coding unit of the current picture, information regarding a coded depth of the maximum coding unit, and hierarchical coding unit pattern information for at least one transformation depth, and determines, based on a first hierarchical coding unit pattern information regarding a chroma component of the transformation unit of a first transformation depth, whether second hierarchical coding unit pattern information regarding chroma components of four transformation units of a second transformation depth split from the transformation unit of the first transformation depth has been encoded;
• and
• a decoder which decodes the encoded image data of the chroma component of the transformation unit, based on the obtained information regarding the coded depth of the maximum coding unit and the hierarchical coding unit pattern information,
• wherein the maximum coding unit comprises the transformation unit for performing transformation on the maximum coding unit, the transformation unit is hierarchically split according to the at least one transformation depth, and the second transformation depth is lower than the first transformation depth.