Calibration method of fish-eye lens imaging system applied to target detection

Abstract

The invention discloses a calibration method of a fish-eye lens imaging system applied to target detection, which comprises the step of mathematical modeling of the fish-eye lens imaging system based on an equidistant projection and the precise calibrations of the intrinsic parameters of the imaging system (including the central point O3(u,v) of an imaging surface), the distance L between the top section of the fish-eye lens and a theoretic refractive optical center plane, the radial distortion coefficient K of the fish-eye lens, an image element aspect scale factor i, the plane torsional angle gamma between a camera coordinate system and an imaging surface coordinate system, various parameter calibration methods and matched software. The method aims at the omnidirectional vision system based on the fish-eye lens, analyzes the optical structure and the imaging principle of the fish-eye lens and introduces deformation parameters so as to establish the physical model of the fish-eye lens imaging system and then deduce the mathematical model of the system. With an independently-developed calibration procedure, three-dimensional space information is obtained from a two-dimensional image and applied to the calibration of imaging system parameters. The method is applicable to the calibration of various fish-eye type panoramic lenses, is convenient and accurate and has strong practicability.

Description

【Technical field】: [0001] The invention belongs to the technical field of camera calibration, and in particular relates to the calibration of an all-round vision system established with a fisheye lens and applied to target detection. 【Background technique】: [0002] Imaging system calibration is an essential step in 3D reconstruction, and the results of imaging system calibration directly affect the quality of visual information application. Simply put, imaging system calibration is to determine the parameters of the mapping relationship between three-dimensional space points and two-dimensional image points on the camera imaging plane, and each pixel is obtained through transmission projection. Therefore, the research on the calibration method of the imaging system has important theoretical significance and important practical application value. [0003] The field of view of the fisheye lens can reach 185 degrees, which can realize the stereoscopic vision perception of lar...

AI Technical Summary

Problems solved by technology

Due to the complex internal optical structure of the fisheye lens, generally composed of more than 10 groups of optical lenses, it is difficult to accurately establish the fisheye lens camera model

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