METHOD OF DECODING SYNTAX ELEMENT IN CONTEXT-BASED ADAPTIVE BINARY ARITHMETIC CODING DECODER AND DECODING DEVICE THEREFOR

A method and device for decoding a syntax element are provided. The method includes reading candidate context models which correspond to a syntax element to be decoded; determining a context index increment for the syntax element; selecting a candidate context model of the candidate context models according to the context index increment; and performing binary arithmetic decoding for the syntax element based on the selected candidate context model. The device includes a context model reservoir which reads and stores candidate context models corresponding to a syntax element to be decoded; an increment determining unit which determines a context index increment for the syntax element; a context model selection unit which selects a candidate context model of the candidate context models by using the context index increment; and a decoding unit which performs a binary arithmetic decoding operation for the syntax element based on the selected candidate context model.