摘要
针对桥梁缺陷检测的特点,提出了一种基于数码相机拍照的缺陷尺寸测量方法。通过对人工标识物采用不同位置、不同焦距和不同角度进行拍摄,并利用Matlab软件对照片进行处理,分析缺陷图像像素点与缺陷实际尺寸之间的关系,已达到对相机标定的目的。研究结果表明,缺陷尺寸测量结果误差较小,精度满足要求,满足工程需求。
Considering the characteristic of crack detection of concrete bridge,a digital-camera-based photographic approach of crack dimensional measurement is put forward.In order to achieve the target of calibrating digital camera,the relationship between the crack image pixels and the actual crack dimensions is analyzed by taking pictures of artificial crack objectives face to face,using different focal distances at different place.The pictures are processed by using Matlab software.Based on this measurement,an analysis on the crack of a concrete bridge is carried out.It is observed that the errors of crack length compared with measured values are small and the precision meets the demands.However,the measured width of crack have some errors as a result of the difficulty of crack edge recognition.Some measures should be taken to reduce these errors.
引文
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