Noise is any unwanted information that contaminates an image. Impulse noise is a special type of noise, which has many different origins. Impulse noise of salt and pepper type is typically caused by a malfunction of pixel elements in camera sensors, defective memory locations or timing errors in the scanning process. For images corrupted by salt and pepper noise, noisy pixels can take only the maximum or minimum values in the dynamic range. An important nonlinear filter that will preserve the edges and eliminate impulse noise is the middle of the standard filter (SMF). It replaces each pixel by its median value in its neighborhood and often eliminates the desirable details in the image. Specialized median filters such as the weighted median filter (WMF) were proposed to improve the performance of the median filter by giving more weight to some selected pixels in the filtering window. But they are still implemented evenly across the images regardless of the current pixel if it is noisy or noise-free. Therefore, a noise detection process to discriminate between uncorrupted pixels and damaged pixels is highly desirable. Some of the algorithms based on the decision, such as the Adaptive Median Filter (AMF). These algorithms first detect the noisy pixels and eliminate it by applying the standard medium filter or its variants. These filters are effective in eliminating low to medium density pulse noise only.