Contour-Guided Spectral Routing for Robust Real-Time Pedestrian Detection

Sam Williams; Yuan Xiang

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arXiv · 2609.14383

Contour-Guided Spectral Routing for Robust Real-Time Pedestrian Detection

Sam Williams·Yuan Xiang

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Abstract

Real-time pedestrian detection in driving scenes is constrained by three coupled failure modes: tiny targets lose discriminative evidence, occlusion weakens geometric support, and weather or illumination changes distort appearance statistics. We formulate the detector through a unified \emph{contour-guided spectral routing} view rather than treating frequency processing, attention, and boundary reasoning as independent add-ons. The detector routes information in a prescribed order: spatial evidence is first augmented with global spectral context, deep representations then exchange spatial and spectral cues, and cross-scale fusion is finally conditioned on boundary--semantic disagreement. This ordering yields a compact representation pipeline in which low-frequency context stabilizes global structure while high-frequency evidence protects small-object contours. We further retain a wavelet-subband training transformation that perturbs low- and high-frequency coefficients independently, targeting appearance shifts caused by fog, rain, snow, and low illumination. The formulation exposes a single routing variable at each stage and distinguishes reusable signal transforms from the task-specific policy that decides where each signal is injected. On CityPersons, the proposed detector obtains 70.4 AP$_{50}$ and 44.2 AP$_{50:95}$, compared with 68.1 and 42.2 for RT-DETR, while the full wavelet-augmented configuration reaches 71.1 and 44.6.

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BibTeX RIS

Sam Williams, Yuan Xiang. 2026-09-13. Contour-Guided Spectral Routing for Robust Real-Time Pedestrian Detection. https://arxiv.org/abs/2609.14383

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