Automated Architectural Reconstruction Using Reference Planes under Convex Optimization

In this paper, a method for the automated reconstruction of architectures from two views of a monocular camera is proposed. While this research topic has been studied over the last few decades, we contend that a satisfactory approach has not yet been devised. Here, a new method to solve the same problem with several points of novelty is proposed. First, reference planes are automatically detected using color, straight lines, and edge/vanishing points. This approach is quite robust and fast even when different views and complicated conditions are presented. Second, the camera pose and 3D points are accurately estimated by a two-view geometry constraint in the convex optimization approach. It has been demonstrated that camera rotations are appropriately estimated, while translations induce a significant error in short baseline images. To overcome this problem, we rely only on reference planes to estimate image homography instead of using the conventional camera pose estimation method. Thus, the problem associated with short baseline images is adequately addressed. The 3D points and translation are then simultaneously triangulated. Furthermore, both the homography and 3D point triangulation are computed via the convex optimization approach. The error of back-projection and measured points is minimized in L-infinity-norm so as to overcome the local minima problem of the canonical L-2-norm method. Consequently, extremely accurate homography and point clouds can be achieved with this scheme. In addition, a robust plane fitting method is introduced to describe a scene. The corners are considered as properties of the plane in order to limit the boundary. Thus, it is necessary to find the exact corresponding corner positions by searching along the epipolar line in the second view. Finally, the texture of faces is mapped from 2D images to a 3D plane. The simulation results demonstrate the effectiveness of the proposed method for scenic images in an outdoor environment.