Published By: Blue Eyes Intelligence Engineering

Abstract — Removing impulse noise from digital image is a very challenging research area in digital image processing. In recent years, technological development has significantly improved in analyzing digital images. This paper proposes a modified decision based unsymmetrical trimmed median filter algorithm for the restoration of gray scale and color images that are highly corrupted by salt-and-pepper noise from digital images, by topological approach. 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. The quality of the noise reduction in images is measured by the statistical quantity measures: Root Mean Square Error (RMSE) and Peak-Signal-to-Noise Ratio (PSNR).The proposed algorithm shows better results than the Standard Median Filter (MF)