Hartley Richard, Kang Sing Bing
Department of Information Engineering, Australian National University and National ICT Australia, ACT 0200, Australia.
IEEE Trans Pattern Anal Mach Intell. 2007 Aug;29(8):1309-21. doi: 10.1109/TPAMI.2007.1147.
We propose a method of simultaneously calibrating the radial distortion function of a camera and the other internal calibration parameters. The method relies on the use of a planar (or, alternatively, nonplanar) calibration grid which is captured in several images. In this way, the determination of the radial distortion is an easy add-on to the popular calibration method proposed by Zhang [24]. The method is entirely noniterative and, hence, is extremely rapid and immune to the problem of local minima. Our method determines the radial distortion in a parameter-free way, not relying on any particular radial distortion model. This makes it applicable to a large range of cameras from narrow-angle to fish-eye lenses. The method also computes the center of radial distortion, which, we argue, is important in obtaining optimal results. Experiments show that this point may be significantly displaced from the center of the image or the principal point of the camera.
我们提出了一种同时校准相机径向畸变函数和其他内部校准参数的方法。该方法依赖于使用在多个图像中捕获的平面（或者非平面）校准网格。通过这种方式，径向畸变的确定是对Zhang [24]提出的流行校准方法的一个简单补充。该方法完全是非迭代的，因此极其快速且不受局部最小值问题的影响。我们的方法以无参数的方式确定径向畸变，不依赖于任何特定的径向畸变模型。这使得它适用于从窄角镜头到鱼眼镜头的大范围相机。该方法还计算径向畸变中心，我们认为这对于获得最佳结果很重要。实验表明，这一点可能会明显偏离图像中心或相机的主点。
