A robust active contour initialization and gradient vector flow for ultrasound image segmentation

Speckle and low contrast make ultrasound image segmentation a difficult task. This paper presents an original robust active contour energy and the corresponding quasi-automatic initialization. Both are based on the coefficient of variation gradient vector fl ow. Our approach combines anisotropic diffusion with the gradient vector fl ow field. The gradient vector fl ow is calculated from a map of the amplitudes of the coefficient of variation. This makes it more robust to speckle. The centers of divergence are calculated and used to initialize the active contour model. The method has been tested on different echocardographic images. The results presented are very encouraging.