Contour Estimation in Synthetic and Real Weld Defect Images based on Maximum Likelihood

This paper describes a novel method for automatic estimation of the contours of weld defect in radiography images. Generally, the contour detection is the first operation which we apply in the visual recognition system. Our approach can be described as a region based maximum likelihood formulation of parametric deformable contours. This formulation provides robustness against the poor image quality, and allows simultaneous estimation of the contour parameters together with other parameters of the model. Implementation is performed by a deterministic iterative algorithm with minimal user intervention. Results testify for the very good performance of the approach especially in synthetic weld defect images.

Authors:

• M. Tridi
• N. Nacereddine
• N. Oucief

Keywords:

• Contour
• gaussian
• likelihood
• rayleigh.

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