Abstract: In view of the traditional median filtering reduction method little effect on removing salt and pepper noise of image, we proposed a method of reduction based on noise analysis. According to the characteristics of salt and pepper noise changing only the pixels portion of the image values of 0 and 255, the remaining pixels not, this method determines the noise and signal points of image. For the noise points, it calculates the number of signal in the neighborhood, and then decides to use the median of some neighborhood to replace it according to the number in order to remove the salt and pepper noise points. Simulation results show that the algorithm can effectively remove salt and pepper noise and preserve the edge details of image.

Key words: noise analysis, salt and pepper noise, median filtering