OneFormer3D: One Transformer for Unified Point Cloud Segmentation
Authors: Maxim Kolodiazhnyi, Anna Vorontsova, Anton Konushin, Danila Rukhovich

Semantic instance and panoptic segmentation of 3D point clouds have been addressed using task-specific models of distinct design. Thereby the similarity of all segmentation tasks and the implicit relationship between them have not been utilized effectively. This paper presents a unified simple and effective model addressing all these tasks jointly. The model named OneFormer3D performs instance and semantic segmentation consistently using a group of learnable kernels where each kernel is responsible for generating a mask for either an instance or a semantic category. These kernels are trained with a transformer-based decoder with unified instance and semantic queries passed as an input. Such a design enables training a model end-to-end in a single run so that it achieves top performance on all three segmentation tasks simultaneously. Specifically our OneFormer3D ranks 1st and sets a new state-of-the-art (+2.1 mAP50) in the ScanNet test leaderboard. We also demonstrate the state-of-the-art results in semantic instance and panoptic segmentation of ScanNet (+21 PQ) ScanNet200 (+3.8 mAP50) and S3DIS (+0.8 mIoU) datasets.