Nie Haijiao, Pang Huanli, Ma Mingyang, Zheng Ruikai
School of Computer Science and Engineering, Changchun University of Technology, Changchun 130012, China.
Sensors (Basel). 2024 May 6;24(9):2952. doi: 10.3390/s24092952.
In response to the challenges posed by small objects in remote sensing images, such as low resolution, complex backgrounds, and severe occlusions, this paper proposes a lightweight improved model based on YOLOv8n. During the detection of small objects, the feature fusion part of the YOLOv8n algorithm retrieves relatively fewer features of small objects from the backbone network compared to large objects, resulting in low detection accuracy for small objects. To address this issue, firstly, this paper adds a dedicated small object detection layer in the feature fusion network to better integrate the features of small objects into the feature fusion part of the model. Secondly, the SSFF module is introduced to facilitate multi-scale feature fusion, enabling the model to capture more gradient paths and further improve accuracy while reducing model parameters. Finally, the HPANet structure is proposed, replacing the Path Aggregation Network with HPANet. Compared to the original YOLOv8n algorithm, the recognition accuracy of mAP@0.5 on the VisDrone data set and the AI-TOD data set has increased by 14.3% and 17.9%, respectively, while the recognition accuracy of mAP@0.5:0.95 has increased by 17.1% and 19.8%, respectively. The proposed method reduces the parameter count by 33% and the model size by 31.7% compared to the original model. Experimental results demonstrate that the proposed method can quickly and accurately identify small objects in complex backgrounds.
针对遥感图像中存在的小目标所带来的挑战,如低分辨率、复杂背景和严重遮挡等问题,本文提出了一种基于YOLOv8n的轻量级改进模型。在小目标检测过程中,YOLOv8n算法的特征融合部分与大目标相比,从主干网络中获取的小目标特征相对较少,导致小目标检测精度较低。为了解决这个问题,首先,本文在特征融合网络中添加了一个专门的小目标检测层,以便更好地将小目标的特征融入到模型的特征融合部分。其次,引入了SSFF模块以促进多尺度特征融合,使模型能够捕获更多的梯度路径,在减少模型参数的同时进一步提高精度。最后,提出了HPANet结构,用HPANet取代路径聚合网络。与原始的YOLOv8n算法相比,在VisDrone数据集和AI-TOD数据集上,mAP@0.5的识别准确率分别提高了14.3%和17.9%,而mAP@0.5:0.95的识别准确率分别提高了17.1%和19.8%。与原始模型相比,所提方法的参数数量减少了33%,模型大小减少了31.7%。实验结果表明,所提方法能够在复杂背景下快速、准确地识别小目标。