说明：  小波阈值去噪，比较了软阈值，硬阈值及当今各种阈值计算方法和阈值函数处理方法的性能，通过信噪比及均方差的比较，得出各种的算法的优劣。
(Wavelet threshold denoising compared soft threshold and hard threshold and the current method of calculating the various thresholds and thresholds approach the performance of function, through the signal to noise ratio and mean square deviation of the comparison, the various algorithms advantages and disadvantages.)