Recovering the 3D geometry of a purely texture-less object with generally unknown surface reflectance (e.g. non-Lambertian) is regarded as a challenging task in multi-view reconstruction. The major obstacle revolves around establishing cross-view correspondences where photometric constancy is violated. This paper proposes a simple and practical solution to overcome this challenge based on a co-located camera-light scanner device. Unlike existing solutions, we do not explicitly solve for correspondence. Instead, we argue the problem is generally well-posed by multi-view geometrical and photometric constraints, and can be solved from a small number of input views. We formulate the reconstruction task as a joint energy minimization over the surface geometry and reflectance. Despite this energy is highly non-convex, we develop an optimization algorithm that robustly recovers globally optimal shape and reflectance even from a random initialization. Extensive experiments on both simulated and real data have validated our method, and possible future extensions are discussed.
翻译:在多视图重建中,对纯无纹理的物体进行三维几何法回收,其表面反射一般不为人知(如非Lambertian),被视为一项具有挑战性的任务。主要障碍是,在光度凝固被破坏的情况下,建立交叉视图通信系统。本文件提出了克服这一挑战的简单而实用的解决办法,其依据是共用的照相机-光扫描仪设备。与现有的解决办法不同,我们没有为通信明确解决。相反,我们认为,这一问题一般都由多视图的几何和光度限制所妥善保护,可以通过少量的投入观点加以解决。我们把重建任务设计为在地表几何测量和反射上联合减少能源。尽管这种能源高度不相近,但我们还是制定了一种优化的算法,能够有力地恢复全球最佳形状,甚至从随机初始化中反射。关于模拟和真实数据的广泛实验验证了我们的方法,并讨论了未来可能的扩展。