| 摘要 |
PURPOSE: To provide an acoustic velocity change system with which sounds closer to the sound quality of original recorded sounds can be provided even when reproducing speed is changed. CONSTITUTION: The acoustic velocity of an input audio signal is changed based on a signal showing the prescribed change of acoustic velocity, afterwards, filtering processing is performed to this changed acoustic velocity signal, and the audio signal having increased short-time correlation is generated. This change of the input audio signal is performed by inserting a sequence before a sample corresponding to a pitch cycle into the input audio signal. As the other method, this input audio signal is changed by removing the sequence of the sample corresponding to the pitch cycle from the input audio signal. Besides, synergy and velocity change operation for voice coding is performed. The filtering processing required for velocity change operation is performed by the linear predictive filter of voice coding. The pitch cycle required for this velocity change operation is the known parameter of a voice decoding device. |
