基于双目立体视觉的3D物体颜色测量方法研究  

Study of Color Measurement Method Based on Binocular 3D Stereo Vision

作　　者：圣延聪 崔桂华[1] 吴自然[1] SHENG Yancong;CUI Guihua;WU Ziran(College of Electrical and Electronic Engineering,Wenzhou University,Wenzhou,China 325035)

机构地区：[1]温州大学电气与电子工程学院,浙江温州325035

出　　处：《温州大学学报（自然科学版）》2022年第1期51-62,共12页Journal of Wenzhou University(Natural Science Edition)

基　　金：国家自然科学基金(61775170);温州市重大科技创新攻关工业项目(ZG2019017);温州市工业科技项目(ZG2020049)。

摘　　要：传统的物体颜色测量方法,均是针对平面物体而言的,不适用于3D物体尤其是表面不规则的3D物体表面的颜色测量.随着3D彩色打印技术的飞速发展,亟需一种快速的直接的3D物体颜色测量方法.鉴于此,提出了一种基于双目立体视觉的3D物体颜色测量方法.在标准LED灯箱中,首先使用双目相机采集标准棋盘格图像进行相机几何参数的标定,利用标定后的相机参数重建物体的3D图像,再采集标准色卡图像进行相机颜色特征化处理,建立3D图像RGB颜色值与CIE XYZ三刺激值之间的数学模型,然后采集被测物图像并从重建的3D图像中提取物体像素点的空间几何信息和颜色信息,实现3D物体的空间位置和颜色的测量.实验中,采用低端网络双目相机和DigiEye 240色卡,训练具有20项三阶多项式的相机特征化模型,模型训练误差为3.5 CIELAB色差单位,用ColorChecker 24色卡作为测试目标物,测试误差为5.7 CIELAB色差单位,略大于训练误差3.5.实验结果表明,该方法具有一定的测量精确度,可以测量传统颜色测量仪器无法测量的3D物体的颜色.Traditional color measurement methods are aimed at planar objects,and are not suitable for color measurement of 3D objects,especially those with irregular 3D surfaces.With the rapid development of 3D color printing technology,a fast and direct 3D object color measurement method is urgently needed.Therefore,a color measurement method based on binocular 3D stereo vision was proposed.In a standard LED lighting cabinet,a binocular camera was first used to collect a standard checkerboard images to compute the camera parameters for reconstructing 3D images of objects;then a standard color chart was used for the camera color characterization to establish a mathematical model between 3D image RGB values and CIE XYZ tristimulus values;finally,the spatial geometric and color information of an object pixel from the reconstructed 3D image was extracted for measuring the geometrical dimension and color of the 3D object.In the experiment,a third order polynomial with twenty terms was trained from a low-profile network binocular camera and a Digi Eye 240 color chart,the training error being about 3.5 CIELAB units;then a Color Checker 24 color chart was used as test target,the average color difference of testing being about 5.7 CIELAB units,slightly greater than 3.5.The experimental results show that the proposed method has certain measurement accuracy,and can measure 3D objects that cannot be measured by traditional color measuring instruments.

关 键 词：双目立体视觉 立体匹配 颜色测量 

分 类 号：TP3[自动化与计算机技术—计算机科学与技术]