An Image Denoising Method Based on Improved Wavelet Thresholding

摘要

This paper proposes an improved-threshold function aimed to enhance the de-noising performance of wavelet thresholding method. Firstly, the theory of wavelet transforms and characteristic of soft-threshold function and hard- threshold function was introduced. Then, an improved-threshold function was proposed. The new method overcomes the discontinuous in hard threshold de-noising method and reduces the permanent bias in soft threshold de-noising method. Last, the improved-threshold algorithm, soft-threshold algorithm, hard-threshold algorithm, disperse wavelet transform (DWT) and wiener filtering are used to reduce the noise in the same image. The experiment result show that the improved- threshold algorithm can get a better denoising effect than the traditional soft and hard thresholding de-noising algorithms.