Hue-saturation-depth Guided Image-based Lidar Upsampling Technique for Ultra-high-resolution and Omnidirectional 3D Scanning

This paper proposes a lidar upsampling technique to obtain ultra-high resolution and omnidirectional 3D data. Obtaining a large amount of omnidirectional 3D data is expensive because of the cost of sensing and scanning systems. Instead of using expensive commercial scanning systems, we introduce a new type of low-cost 360-degree 3D scanning system to obtain 3D lidar data. The original lidar data from the system is upsampled by using the weighted median filter with novel Hue-Saturation-Depth (HSD) guide image. The proposed upsampling technique consists of two steps. The first step upsampling is performed by using linear interpolation based on pixel distance and edge-area refinement in the interpolated depth map. Thereafter, in order to reduce the saturation effect of a high-contrast RGB color guide image, we propose to add the depth information to the guide image. A novel HSD guide image is generated by replacing the intensity of the RGB image with the scaled-depth from the first-step upsampling. Finally, the second-step upsampling is performed by applying the weighted median filter to the result of the first-step upsampling. In the experiments, we present ultra-high-resolution 3D scanning results and error analysis in complex indoor environments.