Hashing that projects data into binary codes has shown extraordinary talents in cross-modal retrieval due to its low storage usage and high query speed. Despite their empirical success on some scenarios, existing cross-modal hashing methods usually fail to cross modality gap when fully-paired data with plenty of labeled information is nonexistent. To circumvent this drawback, motivated by the Divide-and-Conquer strategy, we propose Deep Manifold Hashing (DMH), a novel method of dividing the problem of semi-paired unsupervised cross-modal retrieval into three sub-problems and building one simple yet efficiency model for each sub-problem. Specifically, the first model is constructed for obtaining modality-invariant features by complementing semi-paired data based on manifold learning, whereas the second model and the third model aim to learn hash codes and hash functions respectively. Extensive experiments on three benchmarks demonstrate the superiority of our DMH compared with the state-of-the-art fully-paired and semi-paired unsupervised cross-modal hashing methods.

本论文提出了一种新方法 Deep Manifold Hashing(DMH)，通过基于流形学习的半配对数据来获取模态不变的特征，并构建三个子模型，分别学习哈希编码和哈希函数，解决了现有跨模态哈希方法在数据严重不平衡情况下的性能问题，并在三个基准测试上证明了其优越性。

深度流形哈希: 一种用于半成对无监督跨模态检索的分治方法