Before revision:  In this paper, we propose a novel and flexible backbone framework, namely CBNetV2, to better train existing open-sourced pre-trained backbones under the pre-training fine-tuning protocol .
After revision:  In this paper, we propose a novel and flexible backbone framework, namely CBNetV2, to construct high-performance detectors using existing open-sourced pre-trained backbones under the pre-training fine-tuning protocol .