Real-Time Detection Algorithm for Small-Target Traffic Signs Based on Improved YOLOv5

doi:10.3778/j.issn.1002-8331.2206-0503

Abstract

Abstract: Accurate real-time detection of small target traffic signs in real scenarios is important for autonomous driving. To address the problem of low accuracy of YOLOv5 algorithm in detecting small target traffic signs, a real-time detection algorithm for small target traffic signs based on improved YOLOv5 is proposed. Drawing on the idea of cross-stage local networks, another gradient path is set on the spatial pyramid pooling of YOLOv5 to strengthen the feature extraction capability; the learnable adaptive weights of deep and shallow convolutional features are added to the neck feature fusion to better fuse deep semantic and shallow detail features and improve the detection accuracy of small target traffic signs. To verify the superiority of the proposed algorithm, experimental validation is carried out on the TT100K traffic sign dataset. The experimental results show that the mean average precision（mAP） of the proposed algorithm on small-target traffic signs is 77.3%, which is 5.4 percentage points better than the original YOLOv5, and also outperforms the detection results of SSD, RetinaNet, YOLOX and Swin Transformer. The proposed algorithm runs at 46.2 frame/s, meeting the requirements for real-time detection.

Key words: traffic signs detection, adaptive feature fusion, small object, feature extraction, YOLOv5

摘要： 在真实场景下准确实时检测小目标交通标志对自动驾驶有重要意义，针对YOLOv5算法检测小目标交通标志精度低的问题，提出一种基于改进YOLOv5的小目标交通标志实时检测算法。借鉴跨阶段局部网络思想，在YOLOv5的空间金字塔池化上设置新的梯度路径，强化特征提取能力；在颈部特征融合中增设深、浅卷积特征的可学习自适应权重，更好地融合深层语义和浅层细节特征，提高小目标交通标志的检测精度。为验证所提算法的优越性，在TT100K交通标志数据集上进行了实验验证。实验结果表明所提算法在小目标交通标志上的平均精度均值（mean average precision，mAP）为77.3%，比原始YOLOv5提升了5.4个百分点，同时也优于SSD、RetinaNet、YOLOX、SwinTransformer等算法的检测结果。所提算法的运行速度为46.2?frame/s，满足检测实时性的要求。

关键词: 交通标志检测, 自适应特征融合, 小目标, 特征提取, YOLOv5

HU Junping, WANG Hongshu, DAI Xiaobiao, GAO Xiaolin. Real-Time Detection Algorithm for Small-Target Traffic Signs Based on Improved YOLOv5[J]. Computer Engineering and Applications, 2023, 59(2): 185-193.

胡均平, 王鸿树, 戴小标, 高小林. 改进YOLOv5的小目标交通标志实时检测算法[J]. 计算机工程与应用, 2023, 59(2): 185-193.

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