High Density Salt and Pepper Noise Reduction in Color Images

An improved decision based unsymmetrical trimmed median filter algorithm for denoising the color images that are highly corrupted by salt and pepper noise is proposed in this paper. The proposed algorithm replaces the noisy pixel by trimmed median value when other pixel values, 0’s and 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. This algorithm also finds out the effect of varying window size on denoised image. In the result, it is concluded that 3x3 window size is best for removal of noise at higher density. This proposed algorithm shows better results than the existing Standard Median Filter (SMF) and Decision Based Algorithms (DBA)