摘要
传统小波阈值去噪分为硬阈值去噪和软阈值去噪,而在其去噪过程中,硬阈值函数在一些不连续点处有时会产生伪吉布斯现象;软阈值函数中估计的小波系数与信号的小波信号之间存在恒定偏差。为了去除这些现象,本文提出了几种新阈值函数的改进方案。实验结果表明,新阈值函数消噪后的视觉特性较好,并且信噪比提高,均方根误差有所降低。从而说明这些方法的有效性。
The typical method of threshold in de-noising has two kinds of ways, one of them is hard one and the other is soft . In some cases, such as on the discontinuities points, the Gibbs phenomenon will exhibit when we use hard thresholding function to remove noise of signals and soft hresholding method also has disadvantages. In order to remove the shortings, some new thresholding functions are presented. The results of the experiment show that the vision of de-noising is better and the RMSE of signal has been decreased a lot while the SNR has been increased,which indicates the methods presented in this paper are effective.
出处
《电子测试》
2008年第2期18-22,共5页
Electronic Test
关键词
小波变换
阈值消噪
门限规则
wavelet transform
thresholding denoising
method of threshold
