Research On Image Processing Techniques In Asphalt Pavement Surface Inspection

With the rapid development of national economy, domestic transportation industry has attained prominent achievements among which the total mileage of highway has already ranked second in the world. It is necessary to upgrade the pavement surface detecting technique generally so that such numerous highway resources are maintained properly. Large-scale complete set detecting equipments are embodiment of detecting techniques;therefore, their application has profound influence on the long-term development of communication in our country and is supposed to be significant to domestic economy.This dissertation focuses on the image processing and analyzing techniques indeveloping Laser Inspecting System for Driving Property of Asphalt Pavement(LDSDPAP). Having implemented a method combining theory with experiment, itmainly describes core techniques on pavement image analysis, analysis datamanagement and reconstruction of 3D pavement model.First, this dissertation concisely introduces the scheme of detecting system, main hardware structure and software architecture. Second, it particularizes the pavement image processing and analyzing techniques and a high precision hybrid thinning algorithm has been proposed through comparison and synthesis. The algorithm includes two major phases: 1) removing white noise and acnode noise by threshold segmentation and grayscale neighborhood property respectively;2) using B-Spline based barycenter algorithm to finish the pavement image thinning.Third, a NetCDF based analysis data management plan has been discussed. It differs from the relational database system in efficiency of storing pavement analysis data and characterizes an implementation with a minimum delay using multithreading and buffer prefetching techniques to improve the performance of whole system.Finally, there is a full discussion of concept and features of Hoppe method based on subdivision for pavement model reconstruction and an explanation of key parts about how to program reconstruction module combining OpenGL with MFC. Meanwhile, the related coding sections are also presented for demonstration.Being testified by simulation and typical data, the pavement image thinning algorithm, analysis data management plan and pavement model reconstruction method are proved to be feasible and effective. Hence, they can be applied to LDSDPAP and other similar systems.