Dual autoencoder based zero shot learning in special domain

Zero-shot learning aims to learn a visual classifier for a category which has no training samples leveraging its semantic information and its relationship to other categories. It is common, yet vital, in practical visual scenarios, and particularly prominent in the uncharted ocean field. Phytoplankton plays an important part in the marine ecological environment. It is common to encounter the zero-shot recognition problem during the in situ observation. Therefore, we propose a dual autoencoder model, which contains two similar encoder–decoder structures, to tackle the zero-shot recognition problem. The first one is used for the projection from the visual feature space to a latent space, then to the semantic space. Inversely, the second one projects from the semantic space to another latent space, then back to the visual feature space. This structure guarantees the projection from the visual feature space to the semantic space to be more effective, through the stable mutual mapping. Experimental results on four benchmarks demonstrate that the proposed dual autoencoder model achieves competitive performance compared with six recent state-of-the-art methods. Furthermore, we apply our algorithm to phytoplankton classification. We manually annotated phytoplankton attributes to develop a practical dataset for this real and special domain application, i.e., Zero-shot learning dataset for PHYtoplankton (ZeroPHY). Experiment results show that our method achieves the best performance on this real-world application.