A wavelet denoising method based on the improved threshold function

We present an improved method on the basis of wavelet threshold de-noising method. In the new method, a new threshold function is proposed, and a changeable threshold is adopted. The threshold function is continuous and has infinite rank continuous derivative, fully reflects the energy distribution of wavelet coefficients. What is more, the function expression is simple and easy to calculate, so it is suitable for various mathematical processing. The advantages of the traditional threshold methods are retained by the improved method. It is more flexible to deal with the wavelet coefficients in the process of removing the noise in the images. Experimental results show that the noise in the images can be reduced effectively by using the improved method, and it can achieve a better visual effect.