“…Other systems, called Region Based Image Retrieval (Liu, Zhang, Lu, & Ma, 2007) (RBIR), focus their attention on specific image regions instead of the entire content to extract features. In this paper, a graph structure for image representation, called Attributed Relational SIFT-based Regions Graph (ARSRG), is described, analyzed and discussed with reference to previous works (Manzo & Petrosino, 2013;Manzo et al, 2014;Manzo & Pellino, 2019;Manzo, 2019). In particular, new definitions and properties arising from the detailed analysis of the structure are introduced.…”