Speech coding system utilizing a recursive computation technique for improvement in processing speed

USRE36646E · kind E · reissue

Assignee

• Kabushiki Kaisha Toshiba · JP

Inventors

• Masami Akamine · Yokosuka, JP
• Yuji Okuda · Okazaki, JP
• Kimio Miseki · Tokyo, JP

Key dates

• Filing date: Jul 19, 1995
• Grant date: Apr 4, 2000
• Expiry date: Jul 19, 2015

Classification

• Technology area (CPC —): General

Abstract

This invention provides a novel speech coding system which recursively executes a filter-applied "Toeplitz characteristic" by causing a drive signal (i.e., an excitation signal) to be converted into a "Toeplitz matrix" when detecting a pitch period in which distortion of the input vector and the vector subsequent to the application of filter-applied computation to the drive signal vector in the pitch forecast called either "closed loop" or "compatible code book" is minimized. The vector quantization method substantially making up the speech coding system of the invention is characteristically used by the system.