A simultaneous feature adaptation and feature selection method for content-based image retrieval systems
In content-based image retrieval (CBIR) applications, each database needs its corresponding parameter setting for feature extraction. However, most of the CBIR systems perform indexing by a set of fixed and pre-specific parameters. On the other hand, feature selection methods have currently gained considerable popularity to reduce semantic gap. In this regard, this paper is devoted to present a hybrid approach to reduce the semantic gap between low level visual features and high level semantics, through simultaneous feature adaptation and feature selection. In the proposed approach, a hybrid meta-heuristic swarm intelligence-based search technique, called mixed gravitational search algorithm (MGSA), is employed. Some feature extraction parameters (i.e. the parameters of a 6-tap parameterized orthogonal mother wavelet in texture features and quantization levels in color histogram) are optimized to reach a maximum precision of the CBIR systems. Meanwhile, feature subset selection is done for the same purpose. A comparative experimental study with the conventional CBIR system is reported on a database of 1000 images. The obtained results confirm the effectiveness of the proposed adaptive indexing method in the field of CBIR.
feature selection image retrieval gravitational search algorithm adaptive feature extraction parameterized wavelet