Patent ID: 7848923

Claim:
A non-transitory digital multimedia storage device for storing the method of converting a dimension of a vector for vector quantization comprising the steps of: extracting a specific parameter having the pitch period from the input speech signal and then generating a vector of a dimension that varies according to the pitch period; dividing an entire frequency domain of the generated vector of the variable dimension into at least two frequency domains; and converting the vector of the variable dimension into vectors of mutually different fixed dimensions according to the divided frequency domains, wherein in the converting the vector of the variable dimension, when the entire frequency domain of the generated vector of the variable dimension is divided into a low frequency domain and a high frequency domain, vectors of a variable dimension corresponding to the low frequency domain are converted into a vector of a maximum fixed dimension, and vectors of a variable dimension corresponding to the high frequency domain are converted into a vector of a lower fixed dimension, wherein in the step of converting the vector of the variable dimension, when the entire frequency domain of the generated vector of the variable dimension is divided into the low frequency domain f Low and the high frequency domain f High , vectors of a variable dimension are respectively converted into vectors of fixed dimensions by the following formula: L = M Low = f Low f BW × M max , ⁢ K = M High = f High f BW × M fix wherein L and M Low are a fixed dimension of the low frequency domain, K and M high are a fixed dimension of the high frequency domain, f BW is a bandwidth of the input signal, M(max) is a maximum of the variable dimension, and M fix is a specific fixed value of a fixed dimension.