发布时间：2015-01-24 来源：人大经济论坛

通信工程专业论文 目 录 1 绪论1 1.1 课题的研究背景1 1.2 射线实时成像检测技术2 1.3 焊缝射线检测图像处理的研究现状3 1.4 论文章节安排5 2 X-射线数字成像技术6 2.1 X-射线成像基础6 2.2 焊缝X-射线实时成像检测系统设计6 2.2.1 X-射线数字成像系统6 2.2.2 射线图像的放大7 2.2.4 采集分辨率的计算11 2.3 本章小结11 3 焊缝图像的降噪与增强处理12 3.1 射线图像的降质因素12 3.1.1 X射线焊缝图像的特点13 3.1.2 焊缝区域的获取14 3.2 焊缝检测图像去噪处理14 3.2.1 多帧平均去噪14 3.2.2 焊缝检测图像空间平滑滤波15 3.2.3 频域低通滤波17 3.3 焊缝检测图像增强处理18 3.3.1 灰度级线性拉伸18 3.3.2 灰度级非线性拉伸19 3.3.3 基于广义模糊算子的图像增强20 3.4 本章小结22 4 焊缝图像缺陷的提取与分割23 4.1 焊缝检测图像的粗判23 4.2 焊缝图像的减影处理25 4.2.1 灰度曲线拟合及平滑滤波去除背景后的缺陷提取25 4.2.2 基于数学形态学的背景模拟法26 4.6 本章小结29 5 焊缝缺陷分类及特征提取30 5.1 焊缝内常见缺陷分类和焊缝质量分级30 5.1.1 常见焊缝缺陷分类30 5.1.2 焊缝质量分级30 5.2 缺陷的影像特征分析[60-61]31 5.3 用于缺陷识别的特征选择34 5.3.1 特征选择依据和判断[62]34 5.3.2基于专家知识的特征选择35 5.4 边界跟踪39 5.5 各种参数的定量计算方法40 5.6 焊缝缺陷识别41 5.7 本章小结44 6 结论45 参考文献47 致 谢51 摘 要 本课题是针对某细长管道焊缝进行焊缝缺陷检测的，管道长5米，焊缝为直线缝。本项目的主要目的是建立一个焊缝缺陷自动检测系统，检测焊缝中存在的缺陷并自动评定缺陷的大小及位置，最后对焊缝进行评定与评级。根据课题的研创要求，结合模糊数学、数学形态学以及数字图像处理技术，力求寻找一种快速有效的缺陷实时增强、缺陷提取和缺陷分割的方法，使其在提取效果和处理速度上都获得令人满意的效果，最后实现该产品焊缝的自动检测。 掌握焊缝射线图像的特点和相关降噪和增强技术理论及方法的基础上，理解选题的应用背景和技术背景，理解选题的意义，采用多种降噪和增强技术方法对焊缝射线图像进行处理，要求达到图像信噪比高，清晰度高，并分析比较效果；完成相应算法。 关键词 ：焊缝，射线，图像处理 Weld-ray image detection technology research Abstract This topic is aims at some tall and slender pipeline welded joint to carry on the welded joint flaw examination, manages the Daoist priest 5 meters, the welded joint for the straight line seam.This project main purpose establishes a welded joint flaw automatic detection system, examines flaw and automatic eva luation flaw size and position which in the welded joint exists, finally carries on the eva luation and the rating to the welded joint.Grinds according to the topic creates the request, the union fuzzy mathematics, mathematics morphology as well as the digital image processing technology, the endeavour seeks one kind of fast effective flaw real-time enhancement, the flaw extraction and the flaw division method, causes it all obtains the satisfying effect in the extraction effect and the processing speed, finally realizes this product welded joint automatic detection. The grasping welded joint beam image characteristic and the correlation noise reduction and the enhancement technology theory and in the method foundation, understood the selected topic the application background and the technical background, understood the selected topic the significance, uses many kinds of noise reduction and the enhancement technology method carries on processing to the welded joint beam image, requests to achieve the image signal-to-noise ratio is high, the clarity is high, and analyzes the comparison effect; Completes the corresponding algorithm 。 Key word：Welded joint，Beam，Imagery processing