面向光环境亮度测量的彩色成像系统光度定标方法

成像系统光度定标是影响其应用于光环境测量的主要因素。本文研究了包括动态范围延展、颜色空间特性化和光亮度绝对定标的彩色成像系统光度定标方法。研究首先通过变积分时间实现成像系统响应函数的相对定标曲线估计,其次基于相对定标曲线对系统进行线性化和动态范围延展,最后使用sRGB到CIE XYZ颜色空间特性化转换矩阵,结合测量数据点对实现了图像Y值与场景亮度之间的映射关系定标。对定标方法进行了实验验证,结果表明的基于本文定标方法的成像测量亮度与实际测量亮度之间的误差低于1.8%。系统定标方法可以有效匹配场景动态范围,对于光环境评估具有重要意义。

Color Imaging System Luminance Calibration Method for Luminance Environment Luminance Measurement

Luminance calibration of imaging system is the main factor that affects its application in optical environment measurement.This paper studies the luminance calibration method of color imaging system including dynamic range extension,color space characterization and absolute brightness calibration.The imaging system response function of the relative calibration curve estimation was achieved through the variable integral time.The system was linearized and extended with dynamic range based on the relative calibration curve.The sRGB characterization to CIE XYZ color space conversion matrix was used and combined with the measuring data points,the mapping relationship calibration was achieved for image Y value and scene luminance.The calibration method is verified by experiments,and the results show that the error between the measured brightness and the measured brightness based on the calibration method in this paper is less than 1.8%.The system calibration method can effectively match the dynamic range of the scene and is of great significance for the assessment of the optical environment.