Polarization image demosaicking using polarization channel difference prior.

This paper presents a simple, yet effective demosaicking technique using polarization channel difference prior for polarization images captured by division of focal plane imaging sensors. The polarization channel difference prior embodies that high frequency energy of difference between orthogonal channels tends to be larger than that between non-orthogonal channels. This paper theoretically proves that this prior is physical valid. For each missing polarization channel at a pixel position, three initial predictions are recovered using different channel differences. The missing polarization channel is estimated by the weighted fusion of the three initial predictions, where the weights are determined by the proposed polarization channel difference prior. The prior helps recover polarization information of the edges, fast and effectively. Experiment results on the polarization dataset demonstrate the effectiveness of the polarization channel difference prior for polarization image demosaicking. The proposed polarization demosaicking method consists of only 16 convolution operations, which makes it fast and parallelizable for GPU acceleration. An image of size 1024×1024 can be processed in 0.33 sec on Ryzen 7 3700X CPU and approximately 60 times faster with RTX 2700 SUPER GPU.