16. The system according to claim 14 , wherein the fundamental frequency difference includes the mean difference and the variance difference of the fundamental frequencies.
14. The system according to claim 10 , wherein the means for selecting a standard speaker from a TTS database further comprises: means for selecting from the TTS database a standard speaker whose acoustic feature difference is minimal according to the fundamental frequency difference and the frequency spectrum difference between the standard voice information of the standard speaker in the TTS database and the source voice information.