ENCODING/DECODING SYSTEM UTILIZING LOCAL PROPERTIES

An encoding/decoding system for sequentially encoding input digital signals and sequentially decoding the encoded signals on the basis of the frequency of occurrence of the input digital signals, thereby improving an encoding efficiency. In a variable length encoding/decoding system, sequential lists of encoded values are used in an encoder and sequential lists of decoded values are stored in a decoder for utilizing the frequency of occurrence of the signals. In a vector quantization encoding/decoding system, the frequency of occurrence of input image signals is used to produce code books for storing vectors that are adjacent to an input vector and to form a block using the input image signals located in the same area in consecutive frames.