Research On Auto-Vectoring Technology Based On Bitmap

Computer Aided Design (CAD) has greatly raised the efficiency of engineering design and can be taken full advantage in developing the following series or improved models. Before CAD found wide use, many companies had kept a large amount of paper-based drawings. There exists great difficulty in maintaining and indexing them. Meanwhile, they cannot be simply reused in the following designs, resulting in a large waste of resources. Raster to vector conversion refers to scanning the paper-based engineering drawings into computer by using the technologies of computer graphics, computer image processing, pattern recognition, etc, and then transferring them into the vector files which can be used by CAD software.Concentrating on the technology of raster to vector conversion, the paper begins with an analysis of the process of raster to vector conversion, followed by the analysis, comparison, and realization of the algorithms in all stages of raster to vector conversion, including scanning, image binarizing, noise-reducing, separation of text from graphics, line vectoring, arc vectoring, as well as an improvement of several algorithms. In the end, the file format of drawing exchange file (DXF) of AutoCAD is analyzed and the vector results are input to the software.On the basis of the discussion of technologies and algorithms, the paper finally realizes a raster to vector conversion software R2VP, capable of accomplishing the whole process of raster to vector conversion, which provides a basis for the later research.