Design of Adaptive-Length Median Filter for Removing Impulse Noise

Many filters have been researched to suppress noise efficiently. However, these filters often exhibit blurring for large window sizes or insufficient noise suppression for small sizes. Median filter with adaptive length[8] was proposed, which could achieve a high degree of noise suppression and still preserve image sharpness. Because this algorithm is dependent on the type of impulse noise, i.e., positive or negative impulse noise, it needs complicated computations to remove mixed impulse noise. In this paper, we propose a developed adaptive-length median filter, which can remove mixed impulse noise effectively at a time. The experimental result shows that the designed filter can achieve the best quality among all filters considered.