Patent ID: 6892164

Claim:
An apparatus for processing a sequence of vectors x n =(x 1 , x 2 , . . . , x n ) selected from a vector value set χ to produce a Bayes mixture density on occurrence of the x n , comprising: a Bayes mixture density calculator having an input that receives a sequence of data x t and a vector value parameter u, and an output, the Bayes mixture density calculator comprising: a first calculator that calculates a probability density p(x t |u) for the sequence of data x t received at the input of the Bayes mixture density calculator; a second calculator, coupled to the first calculator, that calculates a first approximation value of a Bayes mixture density p w (x n ) on the basis of a prior distribution w(u) predetermined by the first calculator to produce the first approximation value; a third calculator, coupled to the first calculator, that calculates a second approximation value of a Bayes mixture m(x n ) on exponential fiber bundle in cooperation with the first calculator to produce the second approximation value; and a fourth calculator, coupled to the second and third calculators, that calculates (1−ε)p w (x n )+ε·m(x n ) by mixing the first approximation value of the Bayes mixture density p w (x n ) with a part of the second approximation value of the Bayes mixture m(x n ) at a rate of 1−ε:ε, where ε is a value smaller than unity, to produce the Bayes mixture density on occurrence of the x n for arithmetic coding during data compression, the Bayes mixture density being output from the Bayes mixture density calculator.