A Segmentation Transfer Approach for Rigid Models

International audienceIn this paper, we propose using a segmented example model to perform a semantic oriented segmentation of rigid 3D models of the same class (tables, chairs, etc.). For this, we introduce an alignment method that maps the meaningful parts of the models and we develop a novel approach based on random walks to transfer a consistent segmentation from the example to the target model. The example-driven segmentation is fast and entirely automatic. We demonstrate the effectiveness of our approach through multiple results of inter-shape segmentation transfer presented for different classes of rigid models

LMSCNet: Lightweight Multiscale 3D Semantic Completion

We introduce a new approach for multiscale 3D semantic scene completion from sparse 3D occupancy grid like voxelized LiDAR scans. As opposed to the literature, we use a 2D UNet backbone with comprehensive multiscale skip connections to enhance feature flow, along with 3D segmentation heads. On the SemanticKITTI benchmark, our method performs on par on semantic completion and better on completion than all other published methods - while being significantly lighter and faster. As such it provides a great performance/speed trade-off for mobile-robotics applications. The ablation studies demonstrate our method is robust to lower density inputs, and that it enables very high speed semantic completion at the coarsest level. Qualitative results of our approach are provided at http://tiny.cc/lmscnet.Comment: For a demo video, see http://tiny.cc/lmscne

Visualization algorithm for CSG polyhedral solids

International audienceAn algorithm is presented here to visualize here to visualize CSG solids in wireframe with hidden faces eliminated. The approach taken is to construct the image of the CSG solid directly from the CSG tree. This algorithm takes into account the face coherence property and the depth of the faces to minimize the number of rays fired during the process. It mixes a two-dimensional polygonal clipping and a ray-casting algorithm