Deep semantics-preserving cross-modal hashing

Cross-modal hashing has been paid widespread attention in recent years due to its outstanding performance in cross-modal data retrieval. Cross-modal hashing can be decomposed into two steps, i.e., the feature learning and the binarization. However, most existing cross-modal hash methods do not take the supervisory information of the data into consideration during binary quantization, and thus often fail to adequately preserve semantic information. To solve these problems, this paper proposes a novel deep cross-modal hashing method called deep semantics-preserving cross-modal hashing (DSCMH), which makes full use of intra and inter-modal semantic information to improve the model's performance. Moreover, by designing a label network for semantic alignment during the binarization process, DSCMH's performance can be further improved. In order to verify the performance of the proposed method, extensive experiments were conducted on four big datasets. The results show that the proposed method is better than most of the existing cross-modal hashing methods. In addition, the ablation experiment shows that the proposed new regularized terms all have positive effects on the model's performances in cross-modal retrieval. The code of this paper can be downloaded from http://www.scholat.com/laizhihui.