由于具有快速的宽视角成像特性,全向相机引起了计算机视觉界越来越多的关注。但是严重失真的图像也使得后期的处理复杂化,不便于经典的透视相机算法的应用。本文在泰勒成像模型下,推导了柱面全景图的重投影展开过程,同时进一步提出了一种新的Ⅳ面透视全景图的展开方法。这种重投影展开不依赖于精确的全向相机模型参数。两种展开全景图像中每个像素都与3维空间中的一条光线对应,方便了普通相机的外极线校正和3维重建算法的应用。模拟数据和真实图像的实验都表明该算法的有效性。
Omni-directional camera has attracted more attentions in computer vision community due to its quick wide-angle imaging. But the great distortion makes the post-processing complex, which limits the algorithm applications of classical perspective camera. This paper deduces an unwarping algorithm from arbitrary ring omni-directional image to cylinder panorama based on the Taylor model of omni-directional imaging system. And we also present an unwarping method to produce a novel kind of panorama which is composed of N perspective planer images. Both two reprojection unwarpings do not depend on a particular model or accurate parameters of omni-directional system. In the unwarped panoramas,each pixel is assigned with a light ray in the 3D space, which makes the applications of stereo rectification and 3D reconstruction simple. Finally,the experimental results with the simulations and real data illustrate the validity of the proposed method.