Object detection is an important research topic in computer vision,main task of which is to locate and classify targets of interest in pictures.Traffic sign detection,as a subdivision of object detection,plays an important role in the advanced driver-assistance system and automatic driving,and has got peoples attention more and more.In a real-world environment,traffic signs are often in complex backgrounds,and the target sizes are small.These factors can bring difficulties to detect traffic signs efficiently.At the same time,due to the constraints of on-board computing and storage resources,the detection model must be lightweight to have better real-time performance.For this,the dissertation proposes two traffic sign detection models to accommodate the traffic sign detection in vehicle applications,as follows:(1)The dissertation introduces a MSA_YOLOv3 detection method,which can accurately locate and classify small traffic signs in real time.First,data augmentation is achieved using image mixup technology.Second,a multi-scale spatial pyramid pooling block is introducedinto the Darknet53 network to enable the network to learn object features more comprehensively.Finally,a bottom-up augmented path is designed to enhance the feature pyramid in YOLOv3,and the result is to achieve accurate localization of objects by utilizing fine-grained features effecti3 clvely in the lower layers.This method effectively overcomes the defect that the usual deep learning object detection model is not good for the small object detection: after the small target passes through several convolutional layers,it is difficult to find the details on the feature map of the last layer.According to the tests on the TT100 K dataset(which is a dataset for traffic sign detection),the performance of the proposed MSA_YOLOv3 is better than that of YOLOv3 in detecting small traffic signs.The detection speed of MSA_YOLOv3 is 23.81 FPS,and the m AP(mean Average Precision)reaches up to 86%.(2)The L-YOLO object detection model,which is suitable for on-board equipment,reduces the complexity and computation of the model by using partial residual connection on Backbone Network.L-YOLO uses Gaussian box localizaton loss at the detection laye.It reduces FP and improves TP by predicting the uncertainty of bounding box positioning during the detection process.On TAD16 K data set,the m AP of L-YOLO is 2.1% higher than Tiny YOLOv3,45% less parameter amount,46% less calculation amount and 20% higher detection speed.MSA_YOLOv3 can accurately locate small traffic signs by improving the network structure.L-YOLO is a lightweight traffic sign detection model,which can be combined with multi-object tracking technology to apply to intelligent traffic system as a component of edge computing. |