Perceptual Optimization for Point-Based Point Cloud Rendering

Abstract: Point-based rendering is a common method widely used in point cloud rendering. It realizes rendering by turning the points into the base geometry The critical step in point-based rendering is to set an appropriate rendering radius for the base geometry, usually calculated using the average Euclidean distance of the N nearest neighboring points to the rendered point. This method effectively reduces the appearance of empty spaces between points in rendering. However, it also causes the problem that the rendering radius of outlier points far away from the central region of the point cloud sequence could be large, which impacts the perceptual quality. To solve the above problems, we propose an algorithm for point-based point cloud rendering through outlier detection to optimize the perceptual quality of rendering. The algorithm determines whether the detected points are outliers using the combination of local and global geometric features. For the detected outliers, the minimum radius is used for rendering. We examine the performance of the proposed method in terms of both objective quality and perceptual quality. The experimental results show that the peak signal-to-noise ratio (PSNR) of the point cloud sequences is improved under all geometric quantization, and the PSNR improvement ratio is more evident in dense point clouds. Specifically, the PSNR of the point cloud sequences is improved by 3.6% on average compared with the original algorithm. We also show that the proposed method significantly improves the perceptual quality of the rendered point clouds and the results of ablation studies prove the feasibility and effectiveness of the proposed method.

Keywords: point cloud rendering; outlier detection; perceptual optimization; point-based rendering; perceptual quality