title: [Level set method reconciled with a dynamic weighting factor for B-mode ultrasound image segmentation].
abstract: OBJECTIVE
  To modify the level set method for precise and fast segmentation of B-type ultrasound image lesions.
  
  
  METHODS
  Based on the best of region level set method, entropy in the information theory was introduced into image processing to define a dynamic weighting factor that responded to the gradient change of the local gray levels to evaluate the dynamic degree of driven force on each pixel on the contour to the target and background areas. The dynamic weighting factors were reconciled into the regional level set model and led the contour to deform and move during the iterations. As lesion segmentation was classified as local segmentation of a specific area, the calculation was restrained to the local sphere abide by the contour, which greatly reduced the calculation complex.
  
  
  RESULTS
  Experiments on B-type ultrasound images showed improved results of the proposed method with a better accuracy and less time consumption compared with several current level set methods.
  
  
  CONCLUSIONS
  Level set method reconciled with dynamic weighting factor allows a better evaluation of the lesion contour pixels, and the local calculation strategy results in an enhanced segmentation efficiency.
authors.affiliation: Department of Information Technology, Southern Medical University, Guangzhou510515, China.E-mail: yiyang20110130@163.com.
authors.forename: Yi
authors.initials: Y
authors.lastname: Yang
authors.forename: Dekuang
authors.initials: D
authors.lastname: Yu
authors.forename: Hong
authors.initials: H
authors.lastname: Shen
authors.forename: Minfeng
authors.initials: M
authors.lastname: Liu
mesh_terms: D000465:Algorithms; D007091:Image Processing, Computer-Assisted; D008962:Models, Theoretical; D014463:Ultrasonography