1. A computer vision system for detecting and modeling features of a building in a plurality of images, comprising: at least one computer system in communication with a database of aerial imagery; and computer vision system code executed by said at last one computer system, said computer vision system code causing said computer system to: receive a plurality of images, each of said images including a view of a structure; process the plurality of images to identify a plurality of two-dimensional (2D) line segments in each image; process the plurality of 2D line segments to generate a plurality of three-dimensional (3D) line segments; process the plurality of 3D line segments to detect a contour of the structure; process the contour of the structure to infer interior roof lines from the structure; and generate a model of the roof of the structure using the detected contour and interior roof lines.