To address the issue of missed detections of small hotspots caused by the loss of detailed features in photovoltaic hotspot defect detection
this paper proposes an improved method for cross-level local feature fusion based on YOLOv8. The method introduces the BiFormer concept into the YOLOv8 backbone to enhance the model’s ability to extract detailed information. It replaces traditional upsampling methods with a Dysample dynamic upsampling module
better preserving the details of high-resolution feature maps. Additionally
an FCLAHead detection head is designed for cross-level local feature fusion
establishing feature associations across different feature map levels to achieve information complementarity. This fusion operation enhances the feature representation of small hotspots
improving the model’s detection capability for small hotspots across various scenarios. Compared to the base model YOLOv8n
the improved model increases mean average precision (mAP) from 86.3% to 90%
with precision and recall improving by 1.1 and 3.1 percentage points
respectively. The model’s parameter count is only 3.08×10
with a slight increase in computation
making it suitable for applications requiring high accuracy in hardware-limited environments.
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