采用改进的YOLOv5s检测花椒簇

为实现花椒簇的快速准确检测,该研究提出了一种基于改进YOLOv5s的花椒簇检测模型。首先,使用MBConv(MobileNetV3 block convolution,MBConv)模块和基于ReLU的轻量级自注意力机制优化了EfficientViT网络,用其代替YOLOv5s的主干,减少模型的参数量、增强模型对重要特征的表达能力。其次,在模型的训练过程中采用了OTA(optimal transport assignment)标签分配策略,优化训练中的标签分配结果。最后,使用WIoU损失函数对原损失函数CIoU进行替换,提高锚框的质量。试验结果表明,改进YOLOv5s模型的平均准确度均值(mean average precision,mAP)为97.3%、参数量为5.9 M、检测速度为131.6帧/s。相较于YOLOv5s模型,mAP提升1.9个百分点、参数量降低15.7%、检测速度提高14.5%。结果表明,该研究提出的改进YOLOv5s模型准确度高、参数量低、检测速度快,可实现对花椒簇的有效检测。

Detecting pepper cluster using improved YOLOv5s

Efficient detection of pepper clusters can be crucial to realize the automated harvesting in the development of pepper industry. However, the existing detection of pepper cluster cannot fully meet the large-scale in recent years, due to the low efficiency, generalization, and real-time algorithm. In this study, an improved YOLOv5s model was proposed to accurately detect the pepper clusters in real time. 400 images were collected from the Xuande Pepper Industrial Park, Qinglong County, Guizhou Province, Qianxinan Buyi and Miao Autonomous Prefecture, Guizhou Province, China. 148 images were also downloaded from the Internet, and then screened to enhance data diversity. The collected 548 images were then labeled using the LabelImg tool. In addition, the data enhancement was performed on each image and labeled bounding box. Two new images were randomly generated using random rotation and brightness adjustment. As such, a total of 1644 images were obtained as the dataset. Firstly, the EfficientViT network was optimized using the lightweight convolutional neural network (CNN) MobileNetV3 Block Convolution (MBConv) module and the ReLU with lightweight self-attention mechanism. CSPDarkNet53 network was used to replace the backbone of YOLOv5s. The global receptive field of model was enhanced to extract the important features. The better performance was suitable for the targets with the different scales, shapes, and background information. Secondly, Optimal Transport Assignment (OTA) was selected as the label assignment strategy. The optimal label assignment plan was obtained from the global perspective to achieve the effective label assignment. The robustness and accuracy of the model were improved for the complex scenes and target distribution. The WIoU loss function was also used as the bounding box localization of the detector, instead of the CIoU one. At the same time, the high-quality anchor frames were achieved to generate the benefit gradients for the better overall performance of the detector. A common experiment of target detection was performed on a homemade dataset, in order to verify the effectiveness of the improved model. The experimental results show that the improved model was achieved in a mean accuracy (mAP) of 97.3%, a parameter count of 5.9 M, and a detection speed of 131.6 frames per second (FPS). Specifically, the mAP and detection speed of the improved YOLOv5s model increased by 1.9 percentage points, and 14.5%, respectively, whereas, the number of parameters decreased by 15.7%, compared with the original. In addition, the mAP of the improved YOLOv5s model was 8, 16.9, 8.6, and 1.5 percentage points higher than that of EffcientDet-D1, SSD512, RetineNet-R50, and YOLOXs, respectively. The better performance of the improved YOLOv5s was achieved in terms of detection accuracy, detection speed, and number of model parameters. Therefore, the improved YOLOv5s model can be expected to accurately and rapidly detect the pepper clusters.