Random-valued Impulse Noise Reduction in Color Image by Using Switching Vector Median Filter with MST-based Noise Detector

This paper describes the noise reduction performance of a switching vector median filter with a random-valued impulse noise detector for color images. As a random-valued impulse noise detector, a minimum spanning tree (MST)-based method is employed. In the switching vector median filter, the impulse noise detector is employed before filtering, and the detection result is used to judge whether a pixel should be filtered or not. By applying the method to color images, it is expected that the random-valued impulse noise is reduced pointedly while preserving detailed structures such as thin line, sharp corner, and so on. Through some experiments, for color images, the effectiveness of the combination of the switching vector median filter with the MST-based randomvalued impulse noise detector is verified. Particularly, the present method is compared to some powerful switching vector median filters which had been proposed so far from a view point that the impulse noise reduction while preserving edges and details of an image is realized or not.