Salience DETR: Enhancing Detection Transformer with Hierarchical Salience Filtering Refinement
Authors: Xiuquan Hou, Meiqin Liu, Senlin Zhang, Ping Wei, Badong Chen

DETR-like methods have significantly increased detection performance in an end-to-end manner. The mainstream two-stage frameworks of them perform dense self-attention and select a fraction of queries for sparse cross-attention which is proven effective for improving performance but also introduces a heavy computational burden and high dependence on stable query selection. This paper demonstrates that suboptimal two-stage selection strategies result in scale bias and redundancy due to the mismatch between selected queries and objects in two-stage initialization. To address these issues we propose hierarchical salience filtering refinement which performs transformer encoding only on filtered discriminative queries for a better trade-off between computational efficiency and precision. The filtering process overcomes scale bias through a novel scale-independent salience supervision. To compensate for the semantic misalignment among queries we introduce elaborate query refinement modules for stable two-stage initialization. Based on above improvements the proposed Salience DETR achieves significant improvements of +4.0% AP +0.2% AP +4.4% AP on three challenging task-specific detection datasets as well as 49.2% AP on COCO 2017 with less FLOPs. The code is available at https://github.com/xiuqhou/Salience-DETR.