说明：  均匀量化和非均匀量化在性能上存在着显著的差异，这种差异可以用信号通过量化器后的量躁比来反映出来。本程序用曲线表示了理论和实际两个方面下两种量化的量躁比。从而可观察他们的性能上的差别。
(There are significant differences with the function between Uniform quantization and non-uniform quantization ,which can be quantified by SNR from the quantizer.This program use the curves to denote the SNR of theory and practical signal.Then we can observe the performance of the differences.)