Beyond Frequency: Scoring-Driven Debiasing for Object Detection via Blueprint-Prompted Image Synthesis
Xinhao Cai, Liulei Li, Gensheng Pei, Tao Chen, Jinshan Pan, Yazhou Yao, Wenguan Wang
TL;DR
This paper tackles dataset biases in object detection by moving beyond frequency-based debiasing to a representation-focused framework. It introduces Representation Score (RS) to diagnose representational gaps, a dynamic debiasing engine to recalibrate layouts, and a visual blueprint–prompted L2I synthesis paired with a generative alignment mechanism to ensure geometry-faithful data. The approach yields substantial gains for underrepresented object groups and achieves state-of-the-art fidelity in synthetic data generation, with a $15.9$ mAP improvement in layout accuracy and notable mAP gains across rare, border, large, and small objects. The work demonstrates that bias-aware data generation, guided by accurate diagnostics and geometry-preserving prompts, can significantly enhance robustness and generalization in real-world detectors.
Abstract
This paper presents a generation-based debiasing framework for object detection. Prior debiasing methods are often limited by the representation diversity of samples, while naive generative augmentation often preserves the biases it aims to solve. Moreover, our analysis reveals that simply generating more data for rare classes is suboptimal due to two core issues: i) instance frequency is an incomplete proxy for the true data needs of a model, and ii) current layout-to-image synthesis lacks the fidelity and control to generate high-quality, complex scenes. To overcome this, we introduce the representation score (RS) to diagnose representational gaps beyond mere frequency, guiding the creation of new, unbiased layouts. To ensure high-quality synthesis, we replace ambiguous text prompts with a precise visual blueprint and employ a generative alignment strategy, which fosters communication between the detector and generator. Our method significantly narrows the performance gap for underrepresented object groups, \eg, improving large/rare instances by 4.4/3.6 mAP over the baseline, and surpassing prior L2I synthesis models by 15.9 mAP for layout accuracy in generated images.
