High speed search method for LSP quantizer of vocoder

摘要

PURPOSE: A high speed searching method for an LSP quantization apparatus of a sound coder is provided to reduce a searching calculating amount by reducing a searching target code vector range. CONSTITUTION: An optimal arranging location with respect to each code book is determined(S10). An arranging order of the predetermined number of cod vector in each code book is substituted by a new code book arranged according to an element value of a predetermined reference row(S20). An element value of a reference row of the arranged code book is compared with previous and next elements values of a corresponding row of target vector to determine a searching range(S30). An error calculating amount of which is much is obtained to determine an optimal code vector(S40).