Patent ID: 7693707

Claim:
A voice and musical tone coding apparatus, comprising: a quadrature transformation processor that converts a voice and musical tone signal from a time component to a frequency component; an auditory masking characteristic value calculator that finds an auditory masking characteristic value from said voice and musical tone signal; and a vector quantizer that, when one of said voice and musical tone signal frequency component and elements of code vector is within an auditory masking area indicated by said auditory masking characteristic value, performs vector quantization by changing a method of calculating a distance between said voice and musical tone signal frequency component and said elements of code vector based on said auditory masking characteristic value, to a method whereby said distance is calculated by correcting said one of said voice and musical tone signal frequency component and elements of said code vector in said auditory masking area, in a direction where said distance between said voice and musical tone signal frequency component and elements of said code vector is reduced, to a boundary position in said auditory masking area.