- The paper introduces TG-DP, a teacher-guided dual-path architecture that decouples reconstruction and contrastive alignment to effectively reduce semantic noise in audio-visual learning.
- It employs mask ratio tuning and an EMA teacher for distillation, achieving significant improvements in retrieval and classification on VGGSound and AS20K datasets.
- The dual-path design mitigates gradient interference while maintaining inference efficiency, providing robust, transferable representations across modalities.
Semantic Noise Reduction via Teacher-Guided Dual-Path Audio-Visual Representation Learning
Methodological Advances
The paper presents the TG-DP (Teacher-Guided Dual-Path) framework for audio-visual representation learning, addressing semantic noise through a teacher-guided dual-pass architecture. TG-DP strategically separates reconstruction (MAE) and contrastive alignment objectives, each applied to analogously masked input views. This mitigates gradient interference by decoupling the optimization paths, which is not possible in single-pass approaches where both losses operate on a shared representation.
A masked vision transformer encoder processes the input through two forward passes, one for each loss function, while distillation is conducted via an EMA teacher. Teacher-guided masking patterns are introduced to stabilize training, improving robustness and facilitating optimization regularization. Branch-specific mask ratio tuning permits the architecture to optimize retrieval and classification objectives more effectively.
Empirical Evaluation and Results
TG-DP yields performance improvements across major retrieval and classification tasks. On VGGSound, it outperforms DenseAV in both video-to-audio (VโA) and audio-to-video (AโV) retrieval, with R@1 improvements from 24.2/25.1 to 31.3/30.3 and similar gains in R@5 and R@10. Ablative experiments on mask ratio demonstrate that a 0.50 ratio offers superior downstream classification performance, with AS20K mAP increasing from 29.6 to 32.0, while retrieval scores remain competitive.
Unimodal probing on AS20K verifies that TG-DP enhances representation quality beyond cross-modal alignment. Audio-only mAP improved from 29.3 to 31.2, and vision-only mAP from 14.3 to 17.8 relative to CAV-MAE Sync, indicating boosted transferability and semantic integrity in learned features.
TG-DP introduces no inference overhead, as the complexity arises exclusively during pretraining (7.1hโ10.2h), with no additional parameters deployed at test time. This ensures the practicality of the approach for large-scale audio-visual retrieval applications.
Theoretical Considerations and Architectural Implications
The dual-path design allows loss functions to optimize distinct masked representations, effectively mitigating negative gradient interference between reconstruction and alignment. This architectural decoupling exposes a broader regime for mask ratios and branch-specific regularization strategies, demonstrating that constraining contrastive loss masking to zero marginally benefits retrieval but significantly damages downstream classificationโa contradiction that reaffirms the necessity of balanced masking.
Teacher-guided masking acts as an implicit regularizer by enforcing structured visibility patterns, leading to smoother optimization and more robust representations. While its direct impact on instance-level retrieval is ambiguous, it consistently enhances classification performance, suggesting that noise reduction via structured masking confers resilience against semantic confounds.
Practical Implications and Prospective Directions
TG-DP's improvements in cross-modal and unimodal tasks underscore its suitability for semantic retrieval and transfer learning in large-scale multimedia corpora. The absence of inference overhead and focus on modularity allow seamless integration into existing pipelines. The structured masking and branch-specific optimization indicate future potential for further granularity in loss assignment, possibly via adaptive or learned masking policies. Additionally, the measurable advance in representation robustness and transferability suggests applicability in downstream audio, visual, and joint tasks, including few-shot learning and multimodal captioning.
The dual-path paradigm can be generalized to other modalities or multi-objective settings, unlocking new avenues in representation disentanglement and noise reduction. Structured teacher guidance may be extended to hierarchical or semantic-aware masking frameworks, potentially amplifying representation efficiency for complex or noisy datasets.
Conclusion
TG-DP introduces a dual-path, teacher-guided regime for audio-visual representation learning, achieving improved semantic noise reduction and enhanced retrieval and classification performance. The frameworkโs separation of masking and optimization paths mitigates gradient interference and permits targeted regularization, validated by strong numerical results on VGGSound and AS20K. Practically, TG-DPโs inference efficiency and architectural flexibility suggest broad utility in multimodal learning, with theoretical implications for the design of multi-objective pretraining strategies in AI research.