Encoding method and image signal decoding method, encoding method and information source decoding method, devices for them, their programs, and memory medium with registered program

摘要

An information source coding method for encoding a Gauss integer signal, characterized by the method of understanding the steps of: introducing a signal value sequence of the Gauss integer signal as a target (S101) decoding; transform signal values included in the input signal value sequence into integer pairs, each having two integers, arranged in the order (S102) of output; refer to each of the integer pairs as a network point in two-dimensional coordinates, and obtain integer values greater than or equal to zero by performing a two-dimensional, even-dimensional mapping in which the shorter the distance from each network point, the more small is the value assigned to the network point by the mapping (S103); and encode integer values using Golomb codes that can be used to encode an information source that follows an exponential distribution (S104), where a Golomb code code parameter is determined by computing a dispersion of the input signal values and determining the code parameter that has a value in proportion to the computed dispersion.