Symbol spotting in vectorized technical drawings through a lookup table of region strings

Marçal Rusiñol, Josep Lladós, Gemma Sánchez

Research output: Contribution to journalArticleResearchpeer-review

22 Citations (Scopus)


In this paper, we address the problem of symbol spotting in technical document images applied to scanned and vectorized line drawings. Like any information spotting architecture, our approach has two components. First, symbols are decomposed in primitives which are compactly represented and second a primitive indexing structure aims to efficiently retrieve similar primitives. Primitives are encoded in terms of attributed strings representing closed regions. Similar strings are clustered in a lookup table so that the set median strings act as indexing keys. A voting scheme formulates hypothesis in certain locations of the line drawing image where there is a high presence of regions similar to the queried ones, and therefore, a high probability to find the queried graphical symbol. The proposed approach is illustrated in a framework consisting in spotting furniture symbols in architectural drawings. It has been proved to work even in the presence of noise and distortion introduced by the scanning and raster-to-vector processes. © 2009 Springer-Verlag London Limited.
Original languageEnglish
Pages (from-to)321-331
JournalPattern Analysis and Applications
Issue number3
Publication statusPublished - 1 Jan 2010


  • Cyclic string matching
  • Document image analysis
  • Graphical indexing techniques
  • Graphics recognition
  • Symbol spotting


Dive into the research topics of 'Symbol spotting in vectorized technical drawings through a lookup table of region strings'. Together they form a unique fingerprint.

Cite this