An Efficient Method of Solving the P <i>n</i> P Problem for Fisheye Cameras

Fisheye cameras, with their wide field of view, are highly beneficial for applications such as unmanned systems. Solving the perspective- n -point (P n P) problem that estimates the pose of a camera is particularly important for fisheye cameras. However, most existing P n P methods are primarily developed for pinhole cameras, with limited research focusing on fisheye cameras. This study presents an efficient method for solving the P n P problem for fisheye cameras. The proposed method introduces a mapping from a fisheye camera image to a virtual image plane based on the geometric properties of the fisheye camera. Two-dimensional reference points on the virtual plane are then employed to solve the P n P problem. Error analysis validates the effectiveness of the mapping through numerical computation. The experimental results further demonstrate that the proposed method achieves better accuracy and efficiency than the existing methods.