BugNIST -- a Large Volumetric Dataset for Object Detection under Domain Shift
Patrick Møller Jensen, Vedrana Andersen Dahl, Carsten Gundlach, Rebecca Engberg, Hans Martin Kjer, Anders Bjorholm Dahl
TL;DR
BugNIST addresses context shift in volumetric 3D object detection by training on isolated bug volumes and testing on densely packed mixtures where object appearance remains constant but surroundings differ. The dataset includes 9154 individual bug volumes across 12 classes and 388 mixtures, with center-point annotations used for testing, and baseline analyses are provided for context-shift detection. Three detection baselines (Detection U‑Net, 3D Faster R‑CNN, and nnDetection) are evaluated under three training strategies (single bugs, synthetic mixtures, crowded mixtures), using center-point matching with a bounding box inflated by a factor of $1.5$ for alignment. Results show that localization is achievable but class labeling degrades under context shift; U‑Net demonstrates robustness, while the other baselines struggle on mixtures, highlighting the need for context-aware methods. BugNIST thus offers a practical testbed for advancing 3D detection under context shift and supports extensions to segmentation, generative modeling, and morphology analysis in volumetric imaging.
Abstract
Domain shift significantly influences the performance of deep learning algorithms, particularly for object detection within volumetric 3D images. Annotated training data is essential for deep learning-based object detection. However, annotating densely packed objects is time-consuming and costly. Instead, we suggest training models on individually scanned objects, causing a domain shift between training and detection data. To address this challenge, we introduce the BugNIST dataset, comprising 9154 micro-CT volumes of 12 bug types and 388 volumes of tightly packed bug mixtures. This dataset is characterized by having objects with the same appearance in the source and target domains, which is uncommon for other benchmark datasets for domain shift. During training, individual bug volumes labeled by class are utilized, while testing employs mixtures with center point annotations and bug type labels. Together with the dataset, we provide a baseline detection analysis, with the aim of advancing the field of 3D object detection methods.
