Vectorization Of Engineering Drawings And Implementation

Engineering Drawing Vectorization, i.e, raster-to-vector conversion, is the process of analyzing the scanned image of an engineering drawing in paper form and recognizing the graphic objects in the drawing, and finally, generating the vector format. Vectorization is the foundation of the activities of reusing old drawings and the automatic interpretation of engineering drawings. It has been and still is a well-focused topic in CAD research field. In this paper, on the bases of analyzing typical engineering drawing inputting and Vectorization algorithm, This dissertation realizes this Vectorization software using the technology of OOP. It includes image preprocessing, graphics auto-recognition, graphics format conversion and human-computer interactive method, such as raster image edition and vector graphics edition.Image preprocessing includes image filtering, image segment, image thinning, etc. This dissertation explains the thought and implementation technology of these algorithms;Line is basic and the most graphic element in engineering drawing.Line forms many high level graphic elements, for example circel, arc. So the quality of line Vectorization is a very important 'mark in Vectorization performance analyzing.On the bases of analyzing all kinds of lines pixel distribution characteristic, Freeman restriction condition of line chains becomes clear. Line Vectorization is the foundation of other graphic Vectorization. This dissertation analyses the feature of line's Freeman chain code, then brings forward a new line Vectorization method based on probability property model including selecting the next line tracking pixel and the first line mergence procedure. This method can satisfy maximum line extending principle , and can reduce line segmentphenomenon.The paper realizes the Vectorization of conic , circle and arc using curve fitting method. This line vectorization method can recognise line width information.In order to improve the effect of image and the exactitude of vectorization, this dissertation supplies raster image edition and vector graphics edition, which can make pixel operation and amend image vectorization results. At the same time it supplies the image transform to the form of CAD and can be edited and modified in the condition of CAD.This dissertation has just carried on the simple try in the Engineering drawing ectorization respect, too. There are a lot of questions.Luo Zheshuai (Communications Information Engineering & Control) Directed by Mao Qihuang...