NightAdapter: Learning a Frequency Adapter for Generalizable Night-time Scene Segmentation

Night-time scene segmentation is a critical yet challenging task in the real-world applications, primarily due to the complicated lighting conditions. However, existing methods lack sufficient generalization ability to unseen nigh-time scenes with varying illumination.In light of this issue, we focus on investigating generalizable paradigms for night-time scene segmentation and propose an efficient fine-tuning scheme, dubbed as \texttt{NightAdapter}, alleviating the domain gap across various scenes.Interestingly, different properties embedded in the day-time and night-time features can be characterized by the bands after discrete sine transformation, which can be categorized into illumination-sensitive/-insensitive bands.Hence, our \texttt{NightAdapter} is powered by two appealing designs: (1) Illumination-Insensitive Band Adaptation that provides a foundation for understanding the prior, enhancing the robustness to illumination shifts; (2) Illumination-Sensitive Band Adaptation that fine-tunes the randomized frequency bands, mitigating the domain gap between the day-time and various night-time scenes. As a consequence, illumination-insensitive enhancement improves the domain invariance, while illumination-sensitive diminution strengthens the domain shift between different scenes.\texttt{NightAdapter} yields significant improvements over the state-of-the-art methods under various day-to-night, night-to-night, and in-domain night segmentation experiments.We will release our code.