Toward a Unified Complementary Fusion Framework for Robust Polarimetric Imaging

Polarization, as an intrinsic property of light alongside amplitude and phase, has demonstrated great potential in a variety of downstream applications by providing valuable physical cues encoded in the degree of polarization (DoP) and the angle of polarization (AoP). Polarimetric imaging aims to acquire these polarimetric parameters by capturing polarized snapshots. However, compared to conventional imaging, it faces greater difficulties due to the presence of polarizers, which attenuate light intensity in a spatially variant manner. Such attenuation complicates exposure control: a short exposure leads to low signal-to-noise ratio and color distortion, whereas a relatively long exposure increases the risk of motion blur and saturation. To address these challenges, this work proposes PolFusion+, a unified framework that robustly produces clean and sharp polarized snapshots by complementarily fusing a degraded pair of short-exposed noisy and long-exposed blurry inputs. Building upon a polarization-aware three-phase fusion scheme, PolFusion+ introduces two key advancements. First, to handle saturation in the blurry snapshot, the irradiance restoration phase extracts and rectifies color information from both inputs, effectively mitigating saturation-induced degradation. Second, to ensure physically faithful polarization reconstruction, the framework explicitly models the individual characteristics and interdependencies of the DoP and AoP, enabling their joint restoration. These improvements are supported by a degradation-oriented neural network tailored to the fusion scheme. Experimental results demonstrate that PolFusion+ achieves state-of-the-art performance, effectively benefiting downstream applications.