An accurate noise detector for image restoration

This paper proposes a new noise-detection method for restoration of images corrupted by impulsive noise. The proposed method consists of two stages. In the first stage, the pixels classified according to a new flag image are processed by different noise detectors. They are realized by using two median filters with different sizes of windows. In the second stage, each pixel once detected as an impulse in the first stage is verified by using a new system. According to the above stages, the proposed method can accurately detect the location of the impulsive noise and be effectively used as a preprocessor for noise reduction filtering. Experiments show that the proposed method can effectively detect impulsive noises in noisy images even when they are very highly corrupted.