Panasonic Corporation

Panasonic Intellectual Property Management Co., Ltd.

Yuya Shigenobu

Takeshi Furuta

Satoshi Yamaguchi

Nobuo Higaki

Kozo Kimura

Yoshiyuki Wada

Takahiro Kageyama

Masaki Minami

Motokazu Ozawa

An arithmetic decoding device includes a calculating unit that calculates candidates for split information using probability information, the split information indicating a boundary between a first value range and a second value range in range information, the probability information indicating whether a next item of binary data takes the first or second value, and the range information indicating a possible range of positional information obtained from a stream; a selecting unit that selects the split information corresponding to the range information from among the candidates; and a generating unit that generates the binary data according to which range of the range information divided at the split information includes the positional information and generates a next piece of the range information and a next piece of the positional information using the generated binary data. A process of the calculating unit and that of the generating unit are pipelined.

Arithmetic decoding device, image decoding apparatus and arithmetic decoding method

A variable-length code decoding apparatus that decodes a bitstream includes: a storage unit that stores a variable-length code table; a bitstream cutout unit that outputs a bit string of a fixed length; a reference unit that outputs decoded data and a code length with reference to the storage unit; a determination unit that determines whether a bit string of the fixed length is accumulated; a determination unit that determines whether a bit string of a length that is shorter than the fixed length is accumulated; and a selection unit that selects one of the determination results from the determination units. The bitstream cutout unit sets a starting bit based on the selected determination result, and the selection unit switches the selection of the determination results from the determination units.

Variable-length code decoding apparatus and method

A variable length code decoding apparatus according to the present invention includes: an extracting unit which extracts a bit string from a beginning of a bit stream; a first storage unit for storing a plurality of code words in which one piece of data has been 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 have been coded, and decoded data and code lengths respectively corresponding to the code words; a first judging unit which judges whether one of the code words stored in the first storage unit is included in the extracted bit string, and, when judged as being included, outputs the decoded data and the code length of the code word; and a second judging unit which judges whether a code word stored in the second storage unit is included in the extracted bit string, and when judged as being included, outputs the decoded data and the code length of the code word, wherein the extracting unit extracts the bit string to be decoded next in the same cycle as a cycle in which the judgment was made by the first judging unit, and extracts the bit string to be decoded next in a cycle following the cycle in which the judgment was made by the second judging unit.

Variable length code decoding apparatus and method with variation in timing of extracting bit string to be decoded depending on code word

Growing community of inventors

Nara, Japan

Yuya Shigenobu