1. A method for controlling an arithmetic codec context, comprising the steps of: (A) reading a current value indicating one of a first condition and a second condition corresponding to a current context of a plurality of predetermined contexts; (B) generating an input state matching (i) an initial state in response to said first condition and (ii) an output state in response to said second condition, wherein said initial state has a predetermined value and said output state has a value generated by said method before receiving said current context; and (C) generating a current output state by performing an arithmetic code operation on an input signal using said input state.