A Fast and reliable switching median filter for highly corrupted images by impulse noise

In this paper, we propose a fast and reliable impulse noise filter for highly corrupted images. The median filter was once the most popular nonlinear filter for removing impulse noise because of its good denoising power and computational efficiency, but the performance are unsatisfactory when noise ratio is high. So many algorithms have been proposed to improve the filter result. Recently, a switching median filter with boundary discriminative noise detection (BDND) was proposed, it is very effective and outperforms all previously proposed median-based filters, but it´s very time-consuming in calculation. The proposed filter use similar scheme as in BDND, it is also very effective and much more efficient than BDND. The proposed method use a new powerful and efficient noise detection method to determine if current pixel has been corrupted by noise, if it´s corrupted, a variable window median filter is used to attenuate impulse noise, while those uncorrupted pixels are remain unchanged. Results from computer simulations are used to demonstrate pleasing performance of our proposed method.