Evaluating glyph binarizations based on their properties

Document binary images, created by different algorithms, are commonly evaluated based on a pre-existing ground truth. Previous research found several pitfalls in this methodology and suggested various approaches addressing the issue. This article proposes an alternative binarization quality evaluation solution for binarized glyphs, circumventing the ground truth. Our method relies on intrinsic properties of binarized glyphs. The features used for quality assessment are stroke width consistency, presence of small connected components (stains), edge noise, and the average edge curvature. Linear and tree-based combinations of these features are also considered. The new methodology is tested and shown to be nearly as sound as human experts' judgments.