Socially-Aware Tile-Based Point Cloud Multicast with Registration

With the emergence of new applications for holographic-type communication in healthcare, entertainment, and education, point cloud video transmission has become essen-tial. This paper aims to reduce the bandwidth cost by leveraging tile-based video transmission with point cloud registration in a wireless multicast network. A point cloud video is divided into multiple tiles, and each tile contains a portion of point cloud objects and can be registered by adjacent tiles with some similar objects under the registration rotation and registration overlap constraints. We formulate a new optimization problem and prove that it is NP-hard, and then we design an algorithm Multicast Multi-Tile Registration (MMTR) to select multicasting and registered tiles under consideration of socially related users' preferences with the idea of a tile registration graph. A more popular tile can be multicasted to more friends to minimize the bandwidth cost. Experimental results with real datasets show that MMTR can reduce bandwidth costs by more than 20% and achieve better video quality compared to state-of-the-art point cloud transmission algorithms.