Complete and Incomplete Sets of Invariants

The paper shows that the moment invariants proposed recently in this journal by Hjouji et al. (J Math Imaging Vis 62:606-624, 2020) are incomplete, which leads to a limited discriminability. We prove this by means of circular projection of the image. In a broader context, we demonstrate that completeness of the invariants leads to a better recognition power.

Automated summary

The paper demonstrates that the moment invariants proposed by Hjouji et al. are incomplete, leading to limited discriminability. This is proven through circular projection of the image, and in a broader context, completeness of invariants is shown to enhance recognition power.