[1] [1] McAdams H P,Suddarth G A,Ravin C E.Histogram-directed processing of digital chest images.Invest Radiol,1986,21(2):253～259

[2] [2] Pizer S M,Amburm E P.Adaptive histogram equalization and its variations,Computer vision,graphics,and image processing,1990,39(2):355～368

[3] [3] Zimmerman J B,Pizer S M,Staab E V,et al.An evaluation of the effectiveness of adaptive histogram equalization for contrast emhancement.IEEE Trans Med Imaging,1988 7(2):304～312

[4] [4] Fahnestock D,Schowengerdt A.Spatial variant contrast enhancement using local range midification.Optical Engineering,1983,22(3):378～381

[8] [8] Paw lak Z.Rough set:theoretical aspects of reasoning about data.Now ow iejska 15/19,Poland:Warsaw,1990:219～225