  We demonstrate our solution for the 2019 COCO panoptic segmentation task. Our
method first performs instance segmentation and semantic segmentation
separately, then combines the two to generate panoptic segmentation results. To
enhance the performance, we add several expert models of Mask R-CNN in instance
segmentation to tackle the data imbalance problem in the training data; also
HTC model is adopted yielding our best instance segmentation results. In
semantic segmentation, we trained several models with various backbones and use
an ensemble strategy which further boosts the segmentation results. In the end,
we analyze various combinations of instance and semantic segmentation, and
report on their performance for the final panoptic segmentation results. Our
best model achieves $PQ$ 47.1 on 2019 COCO panoptic test-dev data.
