基于级联U-Net的遥感影像道路分割和轮廓提取方法  

Combined Road Segmentation and Contour Extraction for Remote Sensing Images Based on Cascaded U-Net

作　　者：李余 杨祥立 张乐 梁雅麟 高显 杨建喜[1] LI Yu;YANG Xiangli;ZHANG Le;LIANG Yalin;GAO Xian;YANG Jianxi(School of Information Science and Engineering,Chongqing Jiaotong University,Chongqing 400074,China;School of Information and Communication Engineering,University of Electronic Science and Technology of China,Chengdu 611731,China)

机构地区：[1]重庆交通大学信息科学与工程学院,重庆400074 [2]电子科技大学信息与通信工程学院,成都611731

出　　处：《计算机科学》2024年第3期174-182,共9页Computer Science

基　　金：国家自然科学基金(62101081);重庆市教委科学技术研究项目(KJZD-M202000702,KJQN202100747)。

摘　　要：针对基于深度学习的遥感图像道路信息提取模型往往只能输出单任务结果且多任务之间相关性利用不充分的问题,提出了一种基于级联U-Net的道路语义分割和轮廓联合检测方法,将道路语义分割后的特征图与原始图像融合后进行道路轮廓的提取,实现道路语义分割和边界轮廓的联合训练。首先使用U-Net网络结构提取光学遥感图像丰富的层次化特征,通过级联结构将特征串联融合,分别用于提取道路的语义类别和边界轮廓。其次在每级U-Net结构中引入注意力机制模块,进行空间上下文信息和深层次特征提取,改善网络提取过程中出现的细节模糊现象。最后,使用骰子系数和交叉熵误差组成的联合损失函数进行多任务整体训练,实现深度学习模型对遥感图像中道路语义类别和边界轮廓的同时提取。通过在加拿大渥太华城市地区的光学遥感数据集上进行实验,基于级联U-Net的道路信息联合提取方法在分割指标上分别获得了42%的精确度、58%的召回率、48.2%的F1分数以及71.6%的平均交并比,在道路检测指标上取得了0.896的全局最佳阈值(ODS)。结果表明,该模型在满足联合提取道路多任务信息的同时具有更优的检测精度。Aiming at the problem that the deep-learning-based model for road information extraction can only output single-task results and the inadequate use of correlation between multiple tasks,a combined road segmentation and contour extraction method based on cascaded U-Net is proposed,which extracts the road contour after fusing the feature map of road semantic segmentation with the original image.Firstly,the U-Net network structure is used to extract the hierarchical features of optical remote sensing images,and the cascaded U-Net structure is introduced to concatenate the features to extract the pixel-level label and contours of roads respectively.Secondly,the attention mechanism module is added to each stage of U-Net to extract spatial context information and deep level features to improve the detection sensitivity of details.Finally,the joint loss function composed of dice coefficient and cross-entropy error is used for the overall training to extract simultaneously the road semantic segmentation and contour results.On the optical remote sensing dataset of the urban area of Ottawa,Canada,the joint extraction method of road information based on cascaded U-Net achieves 42%precision,58%recall,48.2%F1 score and 71.6%mIoU in the segmentation index,and achieves a global optimal threshold(ODS)of 0.896 in the road detection index.The results show that,the model can meet the requirements of joint extraction of road multi-task information and has better detection accuracy.

关 键 词：遥感影像 道路分割 轮廓提取 级联U-Net 注意力机制 

分 类 号：TP753[自动化与计算机技术—检测技术与自动化装置]