Bag of spatio-visual words for context inference in scene classification

Abstract

In the “bag of visual words (BoVW)” representation each image is represented by an unordered set of visual words. In this paper, a novel approach to encode ordered spatial configurations of visual words in order to add context in the representation is presented. The proposed method introduces a bag of spatio-visual words representation (BoSVW) obtained by clustering of visual words' correlogram ensembles. Specifically, the spherical K-means clustering algorithm is employed accounting for the large dimensionality and the sparsity of the proposed spatio-visual descriptors. Experimental results on four standard datasets show that the proposed method significantly improves a state-of-the-art BoVW model and compares favorably to existing context-based scene classification approaches.