GMOT-40 is the first public dense dataset for Generic Multiple Object Tracking (GMOT). It contains 40 carefully annotated sequences evenly distributed among 10 object categories. Beyond the data, a challenging protocal, one-shot GMOT, is adopted and a series of baseline algorithms is introduced. GMOT-40 is featured in

Dense objects. Over 80 objects of the same class could appear in one frame. High-quality label. Manual annotation with careful inspection in each frame. Diversity in target. Large variability between classes and within the sequences of the same class. Real world challenges. Occlusion, target enter/exiting, motion blur, deformation and so on. Challenging protocol. One-shot GMOT protocol is adopted for evaluation. New baselines. A series of baseline methods for one-shot GMOT task is introduced.