“…For road extraction from satellite and aerial images, a variety of methods have been proposed, using cues Email addresses: e-mail: aboyko@cs.princeton.edu (Aleksey Boyko), e-mail: funk@cs.princeton.edu (Thomas Funkhouser) based mainly on color, monochromatic intensity and texture patterns (Fortier et al, 1999;Mena, 2003). For example, common algorithmic strategies include region growing (Amo et al, 2006;Bicego et al, 2003;Hu et al, 2007;Mena and Malpica, 2005;Tesser and Pavlidis, 2000), segmentation and clustering (Ferchichi and Wang, 2005;Wan et al, 2007), machine learning (Butenuth et al, 2003;Yager and Sowmya, 2003), multi-scale extraction and refinement (Baumgartner and Hinz, 2000;Heipke et al, 1995;Mayer et al, 1998;Steger, 1998), and active contours (Laptev et al, 2000;Peng et al, 2008).…”