基于改进YOLOv5算法的道路目标检测方法

Road object detection method based on improved YOLOv5 algorithm

针对现有网络在道路交通场景下的远处目标识别效果欠佳、目标特征表达不充分及目标定位不准确等目标检测问题,提出一种基于改进YOLOv5算法的道路目标检测方法。首先,总结了YOLOv5算法的特征提取结构,分析出原网络结构的不足之处;其次,在原网络基础上增加小目标检测层,通过补充融合特征层及引入额外检测头,提高网络对远处目标的识别能力;再次,对原检测头进行解耦,通过将边框回归和目标分类过程改为两个分支进行,提升网络对目标特征的表达能力;然后,对先验框进行重聚类,通过K-means++算法调整先验框的高宽比例,增强网络对目标的定位能力;最后,以AP、mAP和FPS为评价指标进行消融、对比和可视化验证实验。结果表明:本文算法在BDD100K数据集上检测速度为95.2帧/s,平均精度达到55.6%,较YOLOv5算法提高6.7%。可见,改进YOLOv5算法在满足检测实时性要求的同时,具备较高的目标检测精度,适用于复杂交通环境下的道路目标检测任务,对提升自动驾驶汽车的视觉感知能力具有指导意义。

Aiming at the object detection problems of the existing network such as poor remote object recognition effect,insufficient object feature expression and inaccurate object positioning,a road object detection method based on the improved YOLOv5 algorithm was proposed.Firstly,the feature extraction structure of YOLOv5 algorithm was summarized,and the shortcomings of the original network structure were analyzed.Secondly,the small object detection layer was added to the original network,and the recognition ability of the network for distant objects was improved by supplementing the fusion feature layer and introducing additional detection heads.Thirdly,the original detection head was decoupled,and the expression ability of the network to object features was improved by changing the border regression and object classification process to two branches.Then,the prior box was reclustered,and the height to width ratio of the prior box was adjusted by the K-means++ algorithm to enhance the network′s ability to locate the object.Finally,AP,mAP and FPS were used as evaluation indicators for ablation,comparison and visual verification experiments.The results show that the detection speed of the proposed algorithm on the BDD100K dataset is 95.2 frames per second,and the average accuracy reaches 55.6%,which is 6.7%higher than that of the YOLOv5 algorithm.It can be seen that the improved YOLOv5 algorithm not only meets the requirements of real-time detection,but also has good object detection accuracy,which is suitable for road object detection tasks in complex traffic environments,and has guiding significance for improving the visual perception ability of autonomous vehicles.