LiDAR Point Cloud Translation Between Snow and Clear Conditions Using Depth Images and GANs.

Snow corrupts LiDAR point clouds with scattered noise points and false objects, posing a serious threat to the perception of autonomous driving systems. Existing effective point cloud de-snow methods are mainly based on outlier filters that rigidly remove isolated points. There are deep-learning and algorithm-based weather models that can handle adverse conditions such as rain and fog, but snow conditions are rarely considered. In this study, we propose a LiDAR point cloud translation model based on refined generative adversarial networks (GANs) that is not only able to de-noise snow in point clouds but also to generate fake snow points on clear data. Our model is trained on depth image representations of point clouds from unpaired datasets, with a customized loss function for grayscale depth images that can maintain scale consistency. A pixel-wise discriminator structure is designed to improve the de-snowing effect around the ego vehicle. The proposed model expresses a better feature capture on snow in LiDAR point clouds, and experiment results show high-quality snow removal performance on both the scattered and clustered snow points, as well as satisfactory fake snow generation on clear road point clouds.