Removal of reflections in LWIR image with polarization characteristics

Long-wave infrared (LWIR) imaging has been successfully used in surveillance applications in low illumination conditions. However, infrared energy reflected from smooth surfaces such as floors and metallic objects may reduce object detection and tracking accuracies. In this paper, we present a novel reflection removal method using polarization properties of the reflection in LWIR imagery. Reflection can be distinguished from the scene by two unique characteristics of polarization: the difference of two orthogonal polarized components (OPC) and the uniformity of angle of polarization (AoP). The OPC difference helps locate the regions of reflection. The uniformity of AoP in the reflection region pose a strong constraint for reflection detection. The proposed joint reflection detection method combines the OPC difference and the uniformity of AoP can detect actual reflection region. Then the closed-form matting method improves the robustness of the method and removes the reflection from the scene. Experiment results demonstrate that the proposed scheme effectively removes the reflection in challenging situations where many existing techniques may fail.