Skeleton generation of engineering drawings via contour matching

doi:10.1016/0031-3203(94)90058-2

Pattern Recognition

Volume 27, Issue 2, February 1994, Pages 261-275

https://doi.org/10.1016/0031-3203(94)90058-2 Get rights and content

Abstract

A new approach for the skeletonization of engineering drawings is proposed. The underlying idea of the proposed approach is totally different from that of the traditional thinning approach. A contour vectorization process is first applied to the contour image of an engineering drawing followed by a contour skeletonization process to obtain the skeleton of the engineering drawing. The resultant description of the drawing is stored in the form of vector instead of raster image. The experimental results show that the speed and storage demand of the proposed approach are much faster and smaller than those of the traditional thinning approach. Besides, the approach does not have the spurious effects bothering most of the thinning algorithms.

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One may think that it is not necessary to apply HT-based methods to engineering drawings since there are already many graphics recognition methods in this domain. In fact, according to our study, the popular graphics recognition methods for engineering drawings, including skeletonization-based methods [17,18], contour-based methods [19] and pixel-tracking methods [20,21], mainly depend on the pixel-level connectivity of graphic elements. As a result, they handle good quality images well, but their performance drops significantly when the image quality is too poor to keep the connectivity.
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Skeleton generation of engineering drawings via contour matching

Abstract

Comput. Graphics

Comput. Graphics Image Process.

Pattern Recognition

Pattern Recognition

Pattern Recognition Lett.

Comput. Vision Graphics Image Process.

Pattern Recognition

CAD/CAM Review & Outlook

A high-level recognizer for schematic diagrams

IEEE Comput. Graphics Applic.