3D Change Localization and Captioning from Dynamic Scans of Indoor Scenes

Yue Qiu, Shintaro Yamamoto, Ryosuke Yamada, Ryota Suzuki, Hirokatsu Kataoka, Kenji Iwata, Yutaka Satoh

Abstract: Daily indoor scenes often involve constant changes due to human activities. To recognize scene changes, existing change captioning methods focus on describing changes from two images of a scene. However, to accurately perceive and appropriately evaluate physical changes and then identify the geometry of changed objects, recognizing and localizing changes in 3D space is crucial. Therefore, we propose a task to explicitly localize changes in 3D bounding boxes from two point clouds and describe detailed scene changes, including change types, object attributes, and spatial locations. Moreover, we create a simulated dataset with various scenes, allowing generating data without labor costs. We further propose a framework that allows different 3D object detectors to be incorporated in the change detection process, after which captions are generated based on the correlations of different change regions. The proposed framework achieves promising results in both change detection and captioning. Furthermore, we also evaluated on data collected from real scenes. The experiments show that pretraining on the proposed dataset increases the change detection accuracy by +12.8% (mAP0.25) when applied to real-world data. We believe that our proposed dataset and discussion could provide both a new benchmark and in-sights for future studies in scene change understanding.