Digital signal encoding device, digital signal decoding device, digital signal arithmetic encoding method and digital signal arithmetic decoding method
In a bit stream syntax containing compressed video slice data for compressed video data of a slice structure, a slice header for compressed video slice data has attached thereto a slice start code, a register reset flag indicating whether a register value, which designates a status of a codeword occurring in an arithmetic coding process, should be reset in the next transmission unit, an initial register value which indicates a register value to be used to start arithmetic coding/decoding to build/decompose the next transmission unit, only when the register reset flag indicates that the register should not be reset.
1. A digital decoding apparatus for receiving and decoding a compression-coded digital signal received in predetermined units, comprising:
an arithmetic decoding unit for decoding the compressed digital signal received in the units according to an arithmetic coding process, wherein
said arithmetic decoding unit initializes a decoding process when decoding of a transmission unit is started, based on information multiplexed into data constituting the transmission unit and representing an arithmetic coding status.
2. The digital signal decoding apparatus according to claim 1 , wherein said arithmetic decoding unit decodes, by determining a probability of occurrence of restored symbols, based on dependence of the digital signal decoded on the signal included in one or a plurality of adjacent transmission units.
3. The digital signal decoding apparatus according to claim 1 , wherein said arithmetic decoding unit learns the probability by counting a frequency of restored symbols.
4. A digital decoding apparatus for receiving and decoding a compression-coded digital signal received in predetermined units, comprising:
an arithmetic decoding unit for decoding the compressed digital signal received in the units according to an arithmetic coding process, wherein
said arithmetic decoding unit initializes a decoding process when decoding of a transmission unit is started, based on information multiplexed into data constituting the transmission unit and representing an arithmetic coding status;
wherein the digital signal is a video signal and the transmission unit is a slice constituted by one or a plurality of macroblocks in a video frame.
5. A digital decoding apparatus for receiving and decoding a compression-coded digital signal received in predetermined units, comprising;
an arithmetic decoding unit for decoding the compressed digital signal received in the units according to an arithmetic coding process, wherein
said arithmetic decoding unit initializes a decoding process when decoding of a transmission unit is started, based on information multiplexed into data constituting the transmission unit and representing an arithmetic coding status;
wherein the digital signal is a video signal and the transmission unit is constructed by collecting coding data in a slice according to a type of the coding data.
6. The digital signal decoding apparatus according to claim 1 , wherein the digital signal is a video signal and the transmission unit is a video frame.