Electronics and Telecommunications Research Institute

C & S Technology Co., Ltd.

Chang Yong Son

Sang Won Kang

Byung Sik Yoon

Jung Chul Lee

Seong Hoon Hong

Hyoung Jung Kim

Yoo Na Sung

Min Kyu Shim

Won Il Lee

A high-speed search method in a speech encoder using an order character of LSP (Line Spectrum Pair) parameters in an LSP parameter quantizer using SVQ (Split Vector Quantization) used in a low-speed transmission speech encoder, includes the steps of rearranging a codebook according to an element value of a reference row for determining a range of code vectors to be searched; and determining a search range by using an order character between a given target vector and an arranged code vector to obtain an optimal code vector. The method gives effects of reducing computational complexity required to search the codebook without signal distortion in quantizing the LSP parameters of the speech encoder using SVQ, and reducing computational complexity without loss of tone quality in G.729 fixed codebook search by performing candidate selection and search on the basis of the correlation value size of the pulse position index.

High-speed search method for LSP quantizer using split VQ and fixed codebook of G.729 speech encoder

A fast search method for LSP (Linear Spectrum Pair) quantization is provided. The fast search method in accordance with an embodiment of the present invention includes the following steps. A first step is obtaining a target vector and a code vector. The target vector and the code vector are converted for ordering property. A second step is generating a code book having the ordering property for sub-matrices by utilizing the target vector and the code vector. A third step is selecting a particular line for determining a search scope in the code books and sorting the code book in descending order with respect to component values of the particular line. A fourth step is determining the search scope by utilizing the ordering property of the target vector and the sorted code vectors. The fifth step is obtaining an error standard by utilizing the target vector and the code vector, and obtaining an optimal code vector by utilizing the error standard within the determined search scope.

Fast search method for LSP quantization

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Seoul, South Korea

Chang Yong Son