Abstract:

A new algorithm of impulse noise removal is proposed based on the characters of image structure and noise. During noise detection a switching method which have two stages is adopted. The min-max operator is used first. Then further detection is conducted by using the information of structure around the pixel. The pixel is identified between noise and signal by a threshold. If it is a noise point, the value is replaced by rank ordered mean (ROM) of the filter window during noise removal. Compared with other several algorithms, the proposed algorithm can protect details of image efficiently while removing fixed valued impulse noise.

Key words: image processing, impulse noise, median filter, noise detection, noise ratio