Patent ID: 6766280
Filing Date: 2004-07-20
Classification: G06F

Abstract:
An apparatus for processing a sequence of vector xn=(x1, x2, . . . , xn) selected from a vector value set &khgr;to produce a Bayes mixture density on occurrence of the xn, comprising:a Bayes mixture density calculator having an input that receives a sequence of data xt and a vector value parameter u, and an output, the Bayes mixture density calculator comprising: a first calculator that calculates, from the sequence of data xt received at the input of the Bayes mixture density calculator, a probability density p(xt|u) for the data xt on curved exponential family; a second calculator, coupled to the first calculator, that calculates a first approximation value of a Bayes mixture density pw(xn) 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(xn) on exponential family including curved exponential family 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 (1âˆ’&egr;)pw(xn)âˆ’&egr;Â·m(xn) by mixing the first approximation value of the Bayes mixture density pw(xn) with a part of the second approximation value of the Bayes mixture m(xn) at a rate of 1âˆ’&egr;:&egr;, where &egr; is a value smaller than unity, to produce the Bayes mixture density on occurrence of the xn for arithmetic coding during data compression, the Bayes mixture density being output from the Bayes mixture density calculator.