CAESAR: concept augmentation based semantic representation for cross-modal retrieval

With the increasing amount of multimedia data, cross-modal retrieval has attracted more attentions in the area of multimedia and computer vision. To bridge the semantic gap between multi-modal data and improve the performance of retrieval, we propose an effective concept augmentation based method, named CAESAR, which is an end-to-end framework including cross-modal correlation learning and concept augmentation based semantic mapping learning. To enhance the representation and correlation learning, a novel multi-modal CNNs based CCA model is developed, which is to capture high-level semantic information during the cross-modal feature learning, and then capture maximal nonlinear correlation. In addition, to learn the semantic relationships between multi-modal samples, a concept learning model named CaeNet is proposed, which is realized by word2vec and LDA to capture the closer relations between texts and abstract concepts. Reenforce by the abstract concept information, cross-modal semantic mappings are learnt with a semantic alignment strategy. We conduct comprehensive experiments on four benchmark multimedia datasets. The results show that our method has great performance for cross-modal retrieval.