The X-ray image from direct digital radiography system is captured in non-uniform and low illumination conditions
and is blurred by noise. A new enhancing method is proposed on the basis of rough set theory and human visual system(HREM). The grays of the original image are stretched
and then the stretched image is used to generate two new images(edge-detail image and smooth image)using the rough set theory and the human visual system. The edge-detail and smooth images are enhanced by the exponential transform and histogram equalization
respectively. Finally
the two enhanced images are overlapped into one image
and the random impulse noise in the overlapped image is reduced. Experimental results show that the HREM method can suppress noise while preserving edge and detail element
and enhance visual effect effectively.
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references
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