公开(公告)号：WO02101718A3

公开(公告)日：2003-04-10

申请号：PCT/IB0202078

申请日：2002-06-07

Applicant: NOKIA CORP ,  NOKIA INC

Inventor： HEIKKINEN ARI ,  RUOPPILA VESA ,  PIETILAE SAMULI

IPC: G10L19/09 ,  G10L19/12 ,  H03M7/30 ,  G10L11/04 ,  G10L13/02 ,  G10L13/04 ,  G10L15/20 ,  G10L19/04

CPC classification number: G10L19/08

Abstract: A method and apparatus for coding successive pitch periods (Fig. 5) of a speech signal. Based on a priori knowledge of statistical properties of successive speech periods, a shaped lattice structure is designed to cover the most probable points in the pitch space. The codebook index search starts with finding an open-loop estimate in the pitch space considering all dimensions and refining the open-loop estimate in a closed-loop search separately in each dimension based on the shaped lattice structure. The closed-loop search for the first subframe is for obtaining an absolute pitch period or a delta pitch while the closed-loop search for each of the other subframes is for obtaining a delta pitch for the respective subframe.

Abstract translation: 一种用于编码语音信号的连续音调周期（图5）的方法和装置。 基于对连续语音周期的统计特性的先验知识，设计了一种形状的格子结构来覆盖音调空间中最可能的点。 码本索引搜索开始于考虑所有维度的音调空间中的开环估计，并且基于形状的格子结构在每个维度中分开地在闭环搜索中优化开环估计。 对于第一子帧的闭环搜索用于获得绝对音调周期或增量音调，而对于每个其他子帧的闭环搜索用于获得相应子帧的增量间距。