Abstract:

The de-noising method by threshold based on wavelet transform is only used to remove Gaussian White Noise and invalid to remove impulse noise.This paper proposes a de-noising method that combines wavelet transform based on novel threshold function and improved median filter.This method can effectively remove fixed noises of the Gaussian White Noise and impulse noise.The simulation experiment shows that combined algorithm for de-noising images of the Peak Signal-Noise Ratio and mean square error is improved over the single algorithm,and the validity of this algorithm is proved.

Key words: mixed noise;improved median filter;wavelet transformation;threshold function