An evaluation of semiautomatic approaches to contour segmentation applied to fungal hyphae

Semiautomatic image analysis techniques are particularly useful in biologic al applications, which commonly generate very complex images, and offer con siderable flexibility. However, systematic study of such methods is lacking ; most research develops fully automatic algorithms. This paper describes a study to evaluate several different semiautomatic or computer-assisted app roaches to contour segmentation within the context of segmenting degraded i mages of fungal hyphae. Four different types of contour segmentation method , with varying degrees and types of user input, are outlined and applied to hyphal images. The methods are evaluated both quantitatively and qualitati vely by comparing results obtained by several test subjects segmenting simu lated images qualitatively similar to the hyphal images of interest. An act ive contour model approach, using control points, emerges as the method to be preferred to three more traditional approaches. Feedback from the image provider indicates that any of the methods described have something useful to offer for segmentation of hyphae.