Text2Loc: 3D Point Cloud Localization from Natural Language
Authors: Yan Xia, Letian Shi, Zifeng Ding, Joao F. Henriques, Daniel Cremers

We tackle the problem of 3D point cloud localization based on a few natural linguistic descriptions and introduce a novel neural network Text2Loc that fully interprets the semantic relationship between points and text. Text2Loc follows a coarse-to-fine localization pipeline: text-submap global place recognition followed by fine localization. In global place recognition relational dynamics among each textual hint are captured in a hierarchical transformer with max-pooling (HTM) whereas a balance between positive and negative pairs is maintained using text-submap contrastive learning. Moreover we propose a novel matching-free fine localization method to further refine the location predictions which completely removes the need for complicated text-instance matching and is lighter faster and more accurate than previous methods. Extensive experiments show that Text2Loc improves the localization accuracy by up to 2x over the state-of-the-art on the KITTI360Pose dataset. Our project page is publicly available at: https: //yan-xia.github.io/projects/text2loc/.