Patent ID: 8208570
Filing Date: 2012-06-26
Classification: G10L

Abstract:
1. A spectrum coding apparatus comprising: an acquisition section that acquires a first spectrum which frequency k is in a band of 0≦k<Fl; an acquisition section that acquires a second spectrum which frequency k is in a band of 0≦k<FH; a normalization section that generates a normalized first spectrum by dividing the first spectrum by a spectrum envelope of the first spectrum; an estimation section that estimates a shape of said second spectrum in a band of FL≦k<FH by the following expression: where S(k) in 0≦k<FL is the normalized first spectrum, S(k) in FL≦k<FH is an estimated second spectrum, and T is a pitch coefficient; and a coding section that codes a pitch coefficient minimizing a distortion between a shape of the estimated second spectrum and the shape of said second spectrum in the band of FL ≦k<FH.