title: Ultrasound image enhancement using structure-based filtering.
abstract: Ultrasound images are prone to speckle noises. Speckles blur features which are essential for diagnosis and assessment. Thus despeckling is a necessity in ultrasound image processing. Linear filters can suppress speckles, but they smooth out features. Median filter based despeckling algorithms produce better results. However, they may produce artifact patterns in the resulted images and oversmooth nonuniform regions. This paper presents an innovative despeckle procedure for ultrasound images. In the proposed method, the diffusion tensor of intensity is computed at each pixel at first. Then the eigensystem of the diffusion tensor is calculated and employed to detect and classify the underlying structure. Based on the classification result, a feasible filter is selected to suppress speckles and enhance features. Test results show that the proposed despeckle method reduces speckles in uniform areas and enhances tissue boundaries and spots.
authors.affiliation: Department of Computer Science, National Taiwan Ocean University, No. 2, Peining Road, Keelung City 202, Taiwan.
authors.forename: Shyh-Kuang
authors.identifier: 0000-0002-9683-4987
authors.initials: SK
authors.lastname: Ueng
authors.affiliation: Chang-Gung Memorial Hospital, No. 222, Mai-Chin Road, Keelung City 204, Taiwan.
authors.forename: Cho-Li
authors.initials: CL
authors.lastname: Yen
authors.affiliation: Department of Computer Science, National Taiwan Ocean University, No. 2, Peining Road, Keelung City 202, Taiwan.
authors.forename: Guan-Zhi
authors.initials: GZ
authors.lastname: Chen
mesh_terms: D000465:Algorithms; D016880:Anisotropy; D016477:Artifacts; D056324:Diffusion Tensor Imaging / Q000379:methods; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D007668:Kidney / Q000000981:diagnostic imaging; D008099:Liver / Q000000981:diagnostic imaging; D016011:Normal Distribution; D012984:Software; D014463:Ultrasonography / Q000379:methods*
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