The Research on an Improved YOLOX-Based Algorithm for Small-Object Road Vehicle Detection

To address the challenges of missed detections and false positives caused by dense vehicle distribution, occlusions, and small object sizes in complex traffic scenarios, this paper proposes an improved YOLOX-based vehicle detection algorithm with three key innovations. First, we design a novel Wavelet-Enhanced Convolution (WEC) module that expands the receptive field to enhance the model’s global perception capability. Building upon this foundation, we integrate the SimAM attention mechanism, which improves feature saturation by adaptively fusing semantic features across different channels and spatial locations, thereby strengthening the network’s multi-scale generalization ability. Furthermore, we develop a Varifocal Intersection over Union (VIoU) bounding-box regression loss function that optimizes convergence in multi-scale feature learning while enhancing global feature extraction capabilities. The experimental results on the VisDrone dataset demonstrate that our improved model achieves performance gains of 0.9% mAP and 1.8% mAP75 compared to the baseline version, effectively improving vehicle detection accuracy.