| 摘要 |
PURPOSE:To provide a voice coder in which signals having a low bit rate that is less than 4kbps are decoded with a high quality. CONSTITUTION:A first partial mutual correlator 403, which is the statistical code book retrieval section of a CELP type voice coder, computes the partial mutual correlation of a long term prediction vector and a terminated impulse response. A second partial mutual correlator 405 computes the partial mutual correlation of an input voice and the terminated impulse response. A partial power computing section 407 computes the partial power of the terminated impulse response. A second error evaluation section executes an error evaluation using the above results so as to retrieve a pulse code vector while making it orthogonal to the long term prediction vector. |
