A concept ontology triplet network for learning discriminative representations of fine-grained classes

Triplet network is an efficient method of metric learning, but with the increase of the number of fine-grained images and sample categories, the training of Triplet network is more and more challengeable. In order to solve this problem, this paper proposes an algorithm that effectively combine Concept Ontology Structure with the Triplet network trained of Two-layer Ontology Loss. It not only utilizes semantic knowledge to guide the Concept Ontology Structure of the network, but also makes use of the relationship between the layers to make the network more effective to see the triplets, which enhances the separability of the learned features. At the same time, we also use the bilinear function jointly trained with the Triplet network to enhance the image details, further improving the performance of the network. Finally, the effectiveness of the proposed algorithm is also proved by the results of classification experiments on the fine-grained image databases - Orchid and Fashion60.