Patent ID: 9479784
Filing Date: 2016-10-25
CPC Classification: H04N

Claim Text:
1. A video decoding method comprising: receiving a bitstream including a transformation unit split flag indicating whether a transformation unit of a current transformation depth is split, the transformation unit being included in a coding unit; determining a context index indicating a context model among a plurality of context models based on a size of the transformation unit of the current transformation depth; obtaining the transformation unit split flag by entropy decoding the bitstream based on the context model indicated by the determined context index; and when the transformation unit split flag indicates a split of the transformation unit of the current transformation depth, splitting the transformation unit of the current transformation depth into four rectangular transformation units of a lower transformation depth, wherein: a rectangular transformation unit has a shape with a width and a height that are a same length, an image is split into a plurality of maximum coding units according to information about the maximum size of the coding unit, a current maximum coding unit among the plurality of maximum coding units is hierarchically split into one or more coding units of depths including at least one of a current depth and a lower depth according to split information, when the split information indicates a split for the current depth, a 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 indicates a non-split for the current depth, one or more transformation units are obtained from the coding unit of the current depth.