Patent ID: 7443320

Claim:
A decoding method of decoding a variable length code to a Run symbol and a Level symbol using a table in which a code number corresponds to the Run symbol and the Level symbol, the Run symbol indicating the number of consecutive coefficients each having a value of zero, and the Level symbol indicating a value of a non-zero coefficient following the Run symbol, said decoding method comprising: decoding a variable length code to a code number; determining whether the code number obtained in said decoding method belongs to one of a first range and a predetermined range; decoding the code number to a Run symbol and a Level symbol by referring to the table, when it is determined that the code number belongs to the first range; and decoding the code number to a Level symbol and then decoding a variable length code following the decoded variable length code to obtain a Run symbol, without referring to the table, when it is determined that the code number belongs to the predetermined range, wherein the first range includes code numbers that exist in the table, and the predetermined range includes code numbers that are larger than the code numbers in the first range.