Redundancy-resistant Generative Hashing for Image Retrieval

Redundancy-resistant Generative Hashing for Image Retrieval

Changying Du, Xingyu Xie, Changde Du, Hao Wang

Proceedings of the Twenty-Seventh International Joint Conference on Artificial Intelligence
Main track. Pages 5017-5023. https://doi.org/10.24963/ijcai.2018/696

By optimizing probability distributions over discrete latent codes, Stochastic Generative Hashing (SGH) bypasses the critical and intractable binary constraints on hash codes. While encouraging results were reported, SGH still suffers from the deficient usage of latent codes, i.e., there often exist many uninformative latent dimensions in the code space, a disadvantage inherited from its auto-encoding variational framework. Motivated by the fact that code redundancy usually is severer when more complex decoder network is used, in this paper, we propose a constrained deep generative architecture to simplify the decoder for data reconstruction. Specifically, our new framework forces the latent hashing codes to not only reconstruct data through the generative network but also retain minimal squared L2 difference to the last real-valued network hidden layer. Furthermore, during posterior inference, we propose to regularize the standard auto-encoding objective with an additional term that explicitly accounts for the negative redundancy degree of latent code dimensions. We interpret such modifications as Bayesian posterior regularization and design an adversarial strategy to optimize the generative, the variational, and the redundancy-resistanting parameters. Empirical results show that our new method can significantly boost the quality of learned codes and achieve state-of-the-art performance for image retrieval.
Keywords:
Uncertainty in AI: Approximate Probabilistic Inference
Machine Learning: Unsupervised Learning
Machine Learning: Deep Learning
Machine Learning: Learning Generative Models
Computer Vision: Recognition: Detection, Categorization, Indexing, Matching, Retrieval, Semantic Interpretation
Computer Vision: Statistical Methods and Machine Learning