INFORMATION ENCODING METHOD, DECODING METHOD, COMMON MULTIPLIER ESTIMATION METHOD, DEVICE USING THESE METHODS, PROGRAM, AND RECORDING MEDIUM

摘要

An object of the present invention is to provide a method for encoding signals by separating a signal by using a common multiplier so as to improve the efficiency of compression of audio signals and a method for calculating a common multiplier of a set of numeric values including errors.

<Paragraphs id="pa02" num="0002" xmlns:base="http://www.sipo.gov.cn/XMLSchema/base">A common multiplier A, of the input signal samples x(i) in each frame is estimated. Each sample x(i) is divided by A, the quotient is rounded to the number of significant digits, and the rounded quotient y(i) is encoded. The quotient y(i) is multiplied by A and the product is subtracted from x(i) to obtain an error signal z(i), which is then encoded. The multiplier A is encoded and the code of y(i), the code of z(i), and the code of A are combined together and outputted.

<Paragraphs id="pa03" num="0003" xmlns:base="http://www.sipo.gov.cn/XMLSchema/base">To estimate the common multiplier, each numeric value is divided by a determined representative value. Irreducible fractions between the maximum positive error and the maximum negative error are obtained by dividing each numeric value by a correct representative value using rational approximation. Among the obtained irreducible fractions, the one having the smallest common denominator of the numeric values is obtained and the common denominator is corrected using the representative value to obtain a common multiplier.