US 7,389,227 B2
High-speed search method for LSP quantizer using split VQ and fixed codebook of G.729 speech encoder
Sang Won Kang, Kyung Ki-do (Korea, Republic of); Chang Yong Son, Seoul (Korea, Republic of); Won Il Lee, Kyung Ki-do (Korea, Republic of); Yoo Na Sung, Seoul (Korea, Republic of); Min Kyu Shim, Seoul (Korea, Republic of); and Seong Hoon Hong, Seoul (Korea, Republic of)
Assigned to C & S Technology Co., Ltd., Seoul (Korea, Republic of)
Filed on Dec. 28, 2000, as Appl. No. 9/749,782.
Claims priority of application No. 2000-1756 (KR), filed on Jan. 14, 2000; application No. 2000-9519 (KR), filed on Feb. 25, 2000; and application No. 2000-18838 (KR), filed on Apr. 11, 2000.
Prior Publication US 2001/0010038 A1, Jul. 26, 2001
Int. Cl. G10L 19/12 (2006.01)
U.S. Cl. 704—222  [704/223] 3 Claims
OG exemplary drawing
 
1. 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, the high-speed search method comprising the steps of:
rearranging a first codebook by replacing the first codebook with a new codebook in which a number of code vectors in the new codebook are arranged in an order according to an element value of a reference row of the first codebook 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,
wherein the rearranging step comprises the steps of:
selecting the reference row in the first codebook by using a plurality of voice data, and then determining an optimal arrangement position (Nm) in which an average search range is minimized; and
replacing the first codebook with the new codebook in which a number (Lm) of code vectors in the new codebook are arranged in a descending order according to the element value of a selected said reference row.