Abstract: Aimed at the accurate segmentation of medical digital image of tongue, this study proposed a tongue segmentation algorithm based on bacteria foraging optimization algorithm (BFOA) and Snake active contour model. Firstly, information entropy threshold method and Kapur algorithm are combined to improve BFOA, and then the improved BFOA is used to get the optimal threshold value, then binarize the tongue image. Secondly, the key contour points of the tongue coating are extracted according to the symmetry. Finally, the B-spline interpolation is performed by using the key points to obtain the closed B-spline curve as the initial contour of the Snake model, by which the external contour of the tongue edge is accurately extracted. The results show that the proposed algorithm can improve the accuracy of tongue segmentation and reduce human-computer interaction.

Key words:  tongue segmentation, bacteria foraging optimization algorithm, Snake model, key points extraction, B-spline curve