IMAGE CODING/DECODING DEVICE AND IMAGE CODING/DECODING METHOD

PROBLEM TO BE SOLVED: To provide an image coding/decoding device which can be accessed at random, can restart decoding even when a transmission error occurs in a code sequence and can reduce an arithmetic amount and to provide an image coding and decoding method. SOLUTION: This coding and decoding device is provided with a selection section 103 that selects in-frame coding or inter-frame coding, a probability table section 111 that has a probability table with respect to each symbol of an information source sequence, an arithmetic coding section 112 that arithmetic- codes the information source sequence based on the probability table to generate a code sequence, a table update section 110 that updates the probability table in response to the frequency of appearance of the symbol and an initializing section 108 that initializes the probability table when the selection section selects the in-frame coding. Thus, since the probability table is initialized when the selection section selects the in-frame coding, an advantageous effect capable of performing random accessing in a prescribed unit and the starting of decoding from the mid-way of the code sequence.