Cross-Modal Retrieval: A Systematic Review of Methods and Future Directions
Tianshi Wang, Fengling Li, Lei Zhu, Jingjing Li, Zheng Zhang, Heng Tao Shen
TL;DR
Cross-modal retrieval addresses the need to semantically align heterogeneous modalities at scale. The paper delivers a comprehensive taxonomy spanning unsupervised and supervised real-value and hashing approaches, plus extensive coverage of methods operating beyond text-image data, including text-video, text-audio, and 3D modalities. It highlights Vision-Language Pre-training and Cross-Modal Generation as pivotal recent directions, and provides benchmarks, evaluation metrics, and an open-source toolbox to accelerate research. The discussion emphasizes efficiency, robustness to uncertainty, and practical deployment considerations, offering concrete directions for future work and impactful applications.
Abstract
With the exponential surge in diverse multi-modal data, traditional uni-modal retrieval methods struggle to meet the needs of users seeking access to data across various modalities. To address this, cross-modal retrieval has emerged, enabling interaction across modalities, facilitating semantic matching, and leveraging complementarity and consistency between heterogeneous data. Although prior literature has reviewed the field of cross-modal retrieval, it suffers from numerous deficiencies in terms of timeliness, taxonomy, and comprehensiveness. This paper conducts a comprehensive review of cross-modal retrieval's evolution, spanning from shallow statistical analysis techniques to vision-language pre-training models. Commencing with a comprehensive taxonomy grounded in machine learning paradigms, mechanisms, and models, the paper delves deeply into the principles and architectures underpinning existing cross-modal retrieval methods. Furthermore, it offers an overview of widely-used benchmarks, metrics, and performances. Lastly, the paper probes the prospects and challenges that confront contemporary cross-modal retrieval, while engaging in a discourse on potential directions for further progress in the field. To facilitate the ongoing research on cross-modal retrieval, we develop a user-friendly toolbox and an open-source repository at https://cross-modal-retrieval.github.io.
