Deep multi-modal clustering (DMC) aims to explore the correlated information from different modalities to improve the clustering performance. Most existing DMCs attempt to investigate the consistency or/and complementarity information by fusing all modalities, but this will lead to the following challenges: 1) Information conflicts between modalities emerge. 2) Information-rich modalities may be weakened. To address the above challenges, we propose a diversity-oriented deep multi-modal clustering (DDMC) method, where the core is dominant modality enhancement instead of multi-modal fusion. Specifically, we select the modality with the highest average silhouette coefficient as the dominant modality, then learn the diversity information between the dominant madality and the remaining ones with diversity learning, and finally enhance the dominant modality for clustering. Extensive experiments show the superiority of the proposed method over several compared DMC methods. To our knowledge, this is the first work to perform multi-modal clustering by enhancing the dominant modality instead of fusion.

Deep multi-modal clustering (DMC) expects to improve clustering performance by exploiting abundant information available from multiple modalities. However, different modalities usually have heterogeneous distribution with uneven quality. This may lead to limited performance, especially for contrastive multi-modal clustering, which inevitably performs contrastive learning between high-quality and low-quality modalities. To tackle this challenge, we propose a novel framework named parameter-free deep multi-modal clustering with reliable contrastive learning (PDMC-RCL). Specifically, the reliable contrastive learning quantifies the relationship between contrastive modality pairs with weight values that will promote the discriminative features learning from useful modality pairs and slow down or even prevent the learning from unreliable modality pairs. Moreover, the reliable contrastive learning is imposed simultaneously at both the feature-level and cluster-level in this framework so that the feature representation learning can benefit from multi-level contrastive learning. It is worth noting that our PDMC-RCL method is parameter-free, which can achieve promising performance without additional hyperparameter tuning. Experimental results on various datasets show the effectiveness of our method over typical state-of-the-art compared DMCs. The source code is available on https://github.com/ShizheHu.