Title:
SPEECH ENCODING DEVICE AND RECORDING MEDIUM
Document Type and Number:
Japanese Patent JP3462958
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To compose a speech source code vector with fidelity to an input speech from a relatively small bit rate in a speech encoding system with a low bit rate of about 4kbits/sec.
SOLUTION: An adaptive code book searching circuit 17 generates an adaptive code vector, and a pitch adaptive speech source code book searching circuit 19 searches a pitch position in the adaptive code vector, and shifts the speech source code vector up to the pitch position by using the sound source code books 201-20n with a lean mode taking the horizontal axis for a distance relative to the pitch position, and searches a vector minimizing a mean-square error of the residual signals with weights. By taking a linear summation of n-pieces of speech code vectors and shifting the obtained vector up to the pitch position, a speech source code vector adaptive to the pitch position is obtained, and when a speech is coded at a low bit rate of about 4kbits/sec, a speech source vector with fidelity to an input speech can be built up in a low operation volume and a low memory capacity.
Inventors:
Takanori Yamanaka
Application Number:
JP17148496A
Publication Date:
November 05, 2003
Filing Date:
July 01, 1996
Export Citation:
Assignee:
Matsushita Electric Industrial Co., Ltd
International Classes:
G10L19/04; G10L19/08; G10L19/12; G10L25/90; H03M7/30; H04B14/04; (IPC1-7): G10L19/12; H03M7/30; H04B14/04
Domestic Patent References:
| JP792999A | ||||
| JP5265496A | ||||
| JP5281998A | ||||
| JP56200A | ||||
| JP7191700A |
Attorney, Agent or Firm:
Masahiro Kurai