Patent ID: 7728745

Claim:
A variable length code decoding apparatus which decodes a bit stream including a code word that is variable-length-coded data, said variable length code decoding apparatus comprising: an extracting unit operable to extract a bit string of at least a maximum code length of a code word used in the variable length coding, from a beginning of an undecoded bit stream; a first storage unit for storing a plurality of code words in which one piece of data is coded, and decoded data and code lengths respectively corresponding to the code words; a second storage unit for storing a plurality of code words in which two or more pieces of data are coded, and decoded data and code lengths respectively corresponding to the code words; a first judging unit operable to judge whether one of the code words stored in said first storage unit is included in the bit string extracted by said extracting unit, and, when judged as being included, to output the decoded data and the code length of the code word; and a second judging unit operable to judge whether one of the code words stored in said second storage unit is included in the bit string extracted by said extracting unit, and, when judged as being included, to output the decoded data and the code length of the code word, wherein said extracting unit is operable, when said first judging unit judges that the code word is included, to judge the beginning of the undecoded bit stream based on the code length outputted by said first judging unit, and to extract a bit string to be decoded next in the same cycle as a cycle in which the judgment was made by said first judging unit, and said extracting unit is operable, when said second judging unit judges that the code word is included, to judge the beginning of the undecoded bit stream based on the code length outputted by said second judging unit, and to extract the bit string to be decoded next in a cycle subsequent to the cycle in which the judgment was made by said second judging unit.