Hierarchical vectorization of electrical drawings in document images by connectivity analysis of symbols and super-components

Abstract

A novel integrated technique is proposed for hierarchical vectorization of electrical drawings in document images. Its first step includes recognition of different electrical symbols and their interconnections based on morphological operations and geometric analysis in three well-distinguished subspaces. This is followed by a hierarchical analysis for detecting the (series-or parallel-connected) super-components in an iterative manner. Finally a compact collection of circuit adjacency lists is produced, which are reduced further by binary encoding. Reconstruction algorithm has also been explained to merit the overall efficacy of the vectorization. Experimental results have been furnished to demonstrate its efficiency and robustness.