隧道洞外亮度自动数码测试分析方法研究

Analytical Methods of the Road Tunnel Ambient Exterior Luminance Using Automatic Digital Test Technology

针对公路隧道洞外亮度L20(S)的自动测试分析方法开展研究,通过理论分析得到数字图像灰度值与曝光量之间呈线性关系,给出了数码成像过程中所拍物体各点的亮度计算公式,采用数码成像技术测试隧道洞外亮度步骤、数码相机感光特性曲线的标定方法以及测试数据处理方法,对都江堰至汶川高速公路上两座已通车运营的隧道进行了现场测试分析,验证了测试方法。最终建立起基于数码成像技术的公路隧道洞外亮度自动测试方法。

By adopting the method of theoretical analysis,digital image grey value has a linear relationship with the exposure,and the calculation formula of luminance in various points of object in digital imaging process has been given. With road tunnel ambient exterior luminance L20（ S） as the research object,and study of the automatic test and analysis methods,the method to analyze road tunnel ambient exterior luminance based on the digital imaging technology has been established. The process of testing road tunnel ambient exterior luminance by digital imaging technology,the method to demarcate sensitometric curve of digital camera,and the method to process test data have been established,eventually a method to automatic testing and analyzing the road tunnel ambient exterior luminance based on digital imaging technology has been established. Using the method of automatic testing and analyzing the road tunnel ambient exterior luminance,to conduct field test and analysis in two tunnels which were open to traffic on the DujiangyanWenchuan highway,we just verified the test method.