一种用于自动驾驶场景的轻量级语义分割网络

Lightweight semantic segmentation network for autonomous driving scenarios

在自动驾驶场景下,针对语义分割模型在车载硬件设备中部署时内存受限且算力不足的问题,需要设计一种较好权衡效率和精度的语义分割模型。采用单分支网络结构,设计了一个轻量级多尺度双向注意力网络。为了实现高效的特征提取,设计了一种轻量级卷积单元来构成网络的特征提取骨干。为了较好地定位和分割道路场景中尺度差异较大的物体,提出了一种多尺度双向注意力模块。它具有全局多尺度感受野,并且在沿一个方向编码通道注意力的同时保留了另一个方向的空间位置信息。基于该注意力模块,设计了跳跃注意力连接模块和特征注意力融合模块,使得输出特征兼具细节信息和语义信息。模型在Cityscapes数据集上以0.9M的参数量,取得了71.86%的平均交并比,同时在单个RTX2080Ti GPU下实现了88FPS的推理速度。实验结果表明,该模型能够实现较高的分割精度,适用于车载硬件下的部署和应用,具有一定的实用价值。

In the autonomous driving scenario,aiming at the problem of limited memory and insufficient computing power when the semantic segmentation model is deployed in vehicle hardware devices,it is necessary to design a semantic segmentation model that can balance efficiency and accuracy.In this paper,a single-branch network structure is used to design a lightweight multi-scale bidirectional attention network.To achieve efficient feature extraction,a lightweight convolutional unit is designed to form the feature extraction backbone of the network.In order to better locate and segment objects with large scale differences in road scenes,a multi-scale bidirectional attention module is proposed which has a global multi-scale receptive field and encodes channel attention in one direction while preserving spatial location information in the other.Based on this attention module,a skip attention connection module and a feature attention fusion module are designed,so that the output features have both detailed information and semantic information.On the Cityscapes dataset,the model in this paper achieves an MIoU(Mean Intersection over Union)of 71.86%with a parameter size of 0.9M,and achieves an inference speed of 88FPS(Frames Per Second)under a single RTX2080Ti GPU.The test results on public datasets show that the model achieves a high segmentation accuracy and is suitable for deployment and application under in-vehicle hardware,which is of certain practical value.