Abstract:
:It is a big challenge to segment magnetic resonance (MR) images with intensity inhomogeneity. The widely used segmentation algorithms are region based, which mostly rely on the intensity homogeneity, and could bring inaccurate results. In this paper, we propose a novel region-based active contour model in a variational level set formulation. Based on the fact that intensities in a relatively small local region are separable, a local intensity clustering criterion function is defined. Then, the local function is integrated around the neighborhood center to formulate a global intensity criterion function, which defines the energy term to drive the evolution of the active contour locally. Simultaneously, an intensity fitting term that drives the motion of the active contour globally is added to the energy. In order to segment the image fast and accurately, we utilize a coefficient to make the segmentation adaptive. Finally, the energy is incorporated into a level set formulation with a level set regularization term, and the energy minimization is conducted by a level set evolution process. Experiments on synthetic and real MR images show the effectiveness of our method.
journal_name
Magn Reson Imagingjournal_title
Magnetic resonance imagingauthors
Liu L,Zhang Q,Wu M,Li W,Shang Fdoi
10.1016/j.mri.2012.10.010subject
Has Abstractpub_date
2013-05-01 00:00:00pages
567-74issue
4eissn
0730-725Xissn
1873-5894pii
S0730-725X(12)00409-2journal_volume
31pub_type
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