The CAS (concentration, asymmetry, smoothness) parameters are a tool originally developed in astronomy to characterize the shapes and images of objects with some central concentration.
Each parameter is a single number which represents some aspect of the structure of the object under study.
It is defined by rotating and subtracting an image by 180 deg from its center.
This parameter has been used in astronomy to determine galaxy mergers and its history.
The smoothness (also called clumpiness) is a measure of the fraction of light in an object which is in small scale structures.