| 摘要 |
PROBLEM TO BE SOLVED: To reduce the coding bit rate of wideband voice signal, without sacrificing the high quality associated with the increased bandwidth. SOLUTION: A bandwidth-adaptive quantization method and apparatus is given for determining the type of acoustic signal and the type of frequency spectrum exhibited by the acoustic signal, in order to selectively delete parameter information before vector quantization. The bits that would otherwise be allocated to the deleted parameters can then be reallocated to the quantization of the remaining parameters, which results in an improvement of the perceptual quality of the synthesized acoustic signal. Alternatively, the bits that would have been allocated to the deleted parameters are dropped which results in an overall bit-rate reduction. COPYRIGHT: (C)2011,JPO&INPIT |
