Performance evaluation for line-drawing recognition systems

In this paper, we discuss a performance evaluator for line-drawing recognition systems on images that contain binary digital logic schematic diagrams, a restricted subclass of engineering line drawings. The evaluator accepts inputs of IGES (the Initial Graphics Exchange Specification) files containing IGES primitives of straight lines, circles, partial arcs of circles, and IGES label block objects. Our evaluator takes two IGES files. One of these files is the recognition algorithm's output and the other IGES file is the corresponding groundtruth. The first step of processing involves parsing each IGES file and extracting IGES entities and the parameter information according to the IGES file format specification. The evaluator performs the evaluation for each pair of entities within these two files based on their types and the matching protocols and matching criteria defined in this paper. The results of our evaluator is a table of numbers which when weighted by application specific weights can be summed to produce an overall score relevant to the application.