Gong Ming, Cao Weiguo, Li Hua. Application of combined shape and color invariants to image retrieval[J]. Journal of Image and Graphics, 2013, 18(8): 990-1003. DOI: 10.11834/jig.20130814.
Image retrieval based on multiple visual features is one of most important direction in the field of content-based image retrieval. Existing retrieval algorithms are based on multiple features mainly combining features through linear weighting. However
this just achieves combinations in the sense of algebra
and the retrieval result is susceptible to the choice of the weights. To solve this problem
including the extraction of shape and color information in the feature extraction procedure
we propose a method to construct combined shape-color features
called shape-color moment invariants
which are invariant to both shape affine transformation and color diagonal-offset transformations. First
we define the shape core and color core in the two-dimensionol geometric space and three-dimensionol color space respectively. Then multiple integrals to the product of shape core and color core are produced. Finally
we get an invariant feature by normalization. Theoretically
this method can derive an infinite number of invariant features while choosing different shape cores or color cores. The experimental results show that this method is distinctive to existing linear weighting method
and has better performance and efficiency when retrieving near-duplicated images