天津大学学报（英文版）
天津大學學報（英文版）
천진대학학보（영문판）
TRANSACTIONS OF TIANJIN UNIVERSITY
2014年
6期
422-428
,共7页
刘会刚%孙菁%张福海%任立儒
劉會剛%孫菁%張福海%任立儒
류회강%손정%장복해%임립유
direction-based filter%impulse noise%noise detection%nonlinear filter%median filter
A direction-based adaptive switching (DBAS) filter is presented for the removal of high-density impulse noise in images. The extrema detection and 28-directional detection are employed to discriminate the pixels as noisy or noise-free. If a pixel is classified as noisy, it will be replaced by a median or a mean value within an adaptive filter window with respect to different noise densities. Simulation results show that the miss-detection ratio and false-alarm ratio are both very low even at noise level as high as 90%. At the same time, better results are obtained in terms of the qualitative and quantitative measures. The peak signal-to-noise ratios increase by nearly 1 dB compared with other existing algorithms. In addition, the computation time is around 10 s for test images with resolutions of 512′512 since the proposed approach has low complexity.
