Reduction of mosquito noise based on the adaptive bilateral-filter

Abstract

Compressing digital image reduces the total size of the digital image file. However, sometimes the processing and displaying of the compressed digital image may lead to “mosquito Noise”. Mosquito Noise derogates the visual effects of the compressed digital image, so in this paper, the reduction of mosquito noise based on the adaptive bilateral-filter is proposed. The gray variation of a pixel's neighborhood region can be used to judge whether the pixel is in the vicinity of the edge. By using gray variation of pixels in the detection window, bilateral-filter's spatial variances and gray variances are adjusted, so that the filtering strength can be adjusted adaptively. Strong filtering is executed for the pixels in the vicinity of the edge, and weak filtering for the pixels in the details. Flat areas are not filtered. The proposed method makes up the shortcoming that traditional reduction of the mosquito noise leads blur to the edges and details by filtering the whole image blindly. It reduces the mosquito noise maximally with details preserved, so as to avoid blurring the image when it is processed.