A definition of word groups exploiting the co-occurrence and proximity of visual words. This representation enriches the discriminative information of images with similar appearance; An online word group database is designed and implemented, providing context-specific representation. Through the integration of direct and inverse index tables, our system achieves efficient loop closure detection suitable for large-scale applications; Temporal consistency and feature distribution information are incorporated directly into the similarity score calculation, complemented by dedicated temporal and geometrical post-verification modules. These additions further improve the system’s precision and recall.
