Indexing technical drawings using title block structure recognition

This paper presents an application that helps to index archives of technical drawings. Indexing consists of extracting information from the title block in order to ensure document retrieval in a database. The indexing information is usually the drawing number and the title. Today, indexing is mostly done manually. By describing the variability of technical drawing forms, this paper explains why classical automated form recognition methods are hardly applicable to technical drawings. We then present a productive and ergonomic application where specification of the area to index is inter-mixed with the process of recognizing the scanned data, avoiding an a priori analysis which requests a high level of expertise. The recognition relies on the structure of the title block, allowing the approach to deal with the variability of real-world technical drawings