Improved YOLO v5 Wheat Ear Detection Algorithm Based on Attention Mechanism

Abstract

The detection and counting of wheat ears are essential for crop field management, but the adhesion and obscuration of wheat ears limit detection accuracy, with problems such as false detection, missed detection, and insufficient feature extraction capability. Previous research results have shown that most methods for detecting wheat ears are of two types: colour and texture extracted by machine learning methods or convolutional neural networks. Therefore, we proposed an improved YOLO v5 algorithm based on a shallow feature layer. There are two main core ideas: (1) to increase the perceptual field by adding quadruple down-sampling in the feature pyramid to improve the detection of small targets, and (2) introducing the CBAM attention mechanism into the neural network to solve the problem of gradient disappearance during training. CBAM is a model that includes both spatial and channel attention, and by adding this module, the feature extraction capability of the network can be improved. Finally, to make the model have better generalization ability, we proposed the Mosaic-8 data enhancement method, with adjusted loss function and modified regression formula for the target frame. The experimental results show that the improved algorithm has an mAP of 94.3%, an accuracy of 88.5%, and a recall of 98.1%. Compared with the relevant model, the improvement effect is noticeable. It shows that the model can effectively overcome the noise of the field environment to meet the practical requirements of wheat ear detection and counting.