SketchSnakes: sketch-line initialized Snakes for efficient interactive medical image segmentation.

We present an intuitive, fast and accurate 2D interactive segmentation method that combines a general subdivision-curve Snake possessing powerful editing capabilities, with a novel sketch-line user initialization process, and a pen input device. Using the pen (or a mouse), the Snake is quickly and precisely initialized with a few quick sketch lines drawn across the width of the target object. The smooth contour constructed using these lines is extremely close to the position and shape of the object boundary. This makes the Snake's task of snapping to the object boundary much simpler and hence more likely to succeed in noisy images with minimal user editing. We apply our Snake to the segmentation of several 2D medical images to demonstrate it's efficiency, accuracy and robustness. We also compare SketchSnakes to Adobe Photoshop's Magnetic Lasso (Adobe Systems Inc., Adobe Photoshop User Guide, 2002) as well as a recent graph-cut based image cutout tool known as Snap (Digital Film Tools LLC, Snap User Guide, 2007) in order to highlight SketchSnakes effectiveness.