面向无人机航拍小目标检测的轻量级YOLOv8检测算法

Lightweight YOLOv8 Detection Algorithm for Small Object Detection in UAV Aerial Photography

针对在无人机图像目标检测中复杂场景下目标特征难提取且小目标容易被淹没在噪声中的问题,提出一种基于YOLOv8s的无人机目标检测算法SC-YOLO。为了能够学习到感兴趣区域的位置细节,基于CA(coordinate attention)提出了SPM(self-positionmodule)注意力。为了缓解Carafe上采样算子因为通道压缩所带来的影响,提出了CEM(Carafeenhancermodule)。通过分析梯度增益函数与数据集中目标大小的关系,使WIoU_v3能够更加关注中、小目标的普通质量锚框,并且在VisDrone2019数据集上进行验证,得到WIoU_v3能够更加关注中、小目标的普通质量锚框的参数设置范围。改进后的YOLOv8s算法在VisDrone2019验证集上的平均均值精度(mAP)提高到43.1%,在测试集上的mAP提高到34.8%,在近几年同等规模的算法中拥有较好的检测性能;改进算法相较基准算法参数量仅增加1.1×10^(6),浮点运算次数(FLOPs)增加1.5 GFLOPs,但在验证集以及测试集上检测精度分别提升了2.0和2.1个百分点;在Tinyperson数据集上的检测精度提高了1.4个百分点。

To address the problems of difficult feature extraction and small targets being overwhelmed by noise in com-plex scenes for target detection in unmanned aerial vehicle(UAV)images,this paper proposes an UAV target detection algorithm called SC-YOLO based on YOLOv8s.Firstly,to learn positional details of regions of interest,a self-position module(SPM)attention based on coordinate attention(CA)is presented.Secondly,to mitigate the impact caused by chan-nel compression of the Carafe upsampling operator,a Carafe enhancer module(CEM)is proposed.Finally,by analyzing the relationship between the gradient gain function and the size of targets in the dataset,this paper enables WIoU_v3 to focus more on the general quality anchor boxes for medium and small targets.This is validated on the VisDrone2019 dataset,where it is found that WIoU_v3 can better target the parameter setting range for general quality anchor boxes of medium and small targets.The improved YOLOv8s algorithm achieves a mean average precision(mAP)of 43.1%on the VisDrone2019 validation set and an mAP of 34.8%on the test set,demonstrating superior detection performance among algorithms of similar scale in recent years.The improved algorithm only adds 1.1×10^(6) in terms of the number of parame-ters and increases the floating point operations(FLOPs)by 1.5 GFLOPs,yet it achieves a 2.0 and 2.1 percentage points in-crease in detection accuracy on the validation and test sets,respectively.On the Tinyperson dataset,the detection accuracy is increased by 1.4 percentage points.