Implementation of Decision Based Algorithm for Median Filter to extract Impulse Noise

This paper presents an accurate and efficient noise detection and filtering algorithm for impulse noise removal. The algorithm includes two stages: noise detection followed by noise filtering. The proposed algorithm replaces the noisy pixel by clipping median value when other pixel values, 0’s or 255’s are present in the selected window and when all the pixel values are 0’s and 255’s then the noise pixel is replaced by mean value of all the elements present in the selected window. Even at high noise densities this algorithm gives better results in comparison with other existing approaches. The proposed algorithm is tested & compared for different grayscale images and it gives better Peak Signal-to-Noise Ratio (PSNR).