WD-FQDet: Multispectral Detection Transformer via Wavelet Decomposition and Frequency-aware Query Learning

TL;DR

WD-FQDet is a multispectral detection transformer that leverages wavelet decomposition and frequency-aware query learning to improve infrared-visible object detection by explicitly modeling frequency domain features.

Contribution

The paper introduces a novel framework that decouples and fuses frequency-specific features from multispectral images, enhancing detection performance.

Findings

Achieves state-of-the-art results on FLIR, LLVIP, and M3FD datasets.

Effectively aligns shared features and preserves modality-specific features.

Dynamic frequency-aware query regulation improves detection across scenarios.

Abstract

Infrared-visible object detection improves detection performance by combining complementary features from multispectral images. Existing backbone-specific and backbone-shared approaches still suffer from the problems of severe bias of modality-shared features and the insufficiency of modality-specific features. To address these issues, we propose a novel detection framework WD-FQDet that explicitly decouples modality-shared and modality-specific information from infrared and visible modalities in the new view of low- and high-frequency domains, allowing fusion strategies tailored to their frequency characteristics. Specifically, a low-frequency homogeneity alignment module is proposed to align modality-shared features across modalities via a cross-modal attention mechanism, and a high-frequency specificity retention module is proposed to preserve modality-specific features through the multi-scale gradient consistency loss. To reinforce the feature representation in the frequency domain, we propose a hybrid feature enhancement module that incorporates spatial cues. Furthermore, considering that the contributions of homogeneous and modality-specific features to object detection vary across scenarios, we propose a frequency-aware query selection module to dynamically regulate their contributions. Experimental results on the FLIR, LLVIP, and M3FD datasets demonstrate that WD-FQDet achieves state-of-the-art performance across multiple evaluation metrics.