Moment invariants have proven to be a useful tool for pattern recognition due to their invariance under translation, scaling and rotation. However the calculation of the moments requires a substantial amount of computer time and this has limited their usefulness in the past. The calculation of all moments up to two dimensions has been implemented solely in hardware for a high resolution image. This reduces the calculation time significantly and makes them suitable for real time applications.
"Real-Time Feature Extraction Using Moment Invariants", Proc. SPIE 0726, Intelligent Robots and Computer Vision V, (27 March 1987); doi: 10.1117/12.937720; https://doi.org/10.1117/12.937720