针对库水位传统量测方法中水尺易锈蚀倾斜,精度低且成本高的问题,该文提出一种不依赖水尺,基于图像匹配的库水位变动识别方法。首先对监控相机拍摄的库坝上游面光学图像进行畸变消除和透视变换,消除相机误差。进一步选取包含水面的感兴...针对库水位传统量测方法中水尺易锈蚀倾斜,精度低且成本高的问题,该文提出一种不依赖水尺,基于图像匹配的库水位变动识别方法。首先对监控相机拍摄的库坝上游面光学图像进行畸变消除和透视变换,消除相机误差。进一步选取包含水面的感兴趣区域(region of interest,ROI)图像进行自适应二值化分割、形态学处理等前处理操作,将水面和库坝特征分离,突出水位线位置。最后,利用归一化互相关匹配算法(normalised cross correlation,NCC)对水位变动前后的两幅图像进行匹配计算,识别水位线变动距离。通过室内试验与现场测试验证上述方法实用性。结果表明:基于图像匹配的库水位动态识别方法可准确识别水位变动,相对误差约为5%,此算法鲁棒性较高。该研究可为库水位自动化、低成本监测提供一种新思路。展开更多
This paper presents a voxel-based region growing method for automatic road surface extraction from mobile laser scanning point clouds in an expressway environment.The proposed method has three major steps:constructing...This paper presents a voxel-based region growing method for automatic road surface extraction from mobile laser scanning point clouds in an expressway environment.The proposed method has three major steps:constructing a voxel model;extracting the road surface points by employing the voxel-based segmentation algorithm;refining the road boundary using the curb-based segmentation algorithm.To evaluate the accuracy of the proposed method,the two-point cloud datasets of two typical test sites in an expressway environment consisting of flat and bumpy surfaces with a high slope were used.The proposed algorithm extracted the road surface successfully with high accuracy.There was an average recall of 99.5%,the precision was 96.3%,and the F1 score was 97.9%.From the extracted road surface,a framework for the estimation of road roughness was proposed.Good agreement was achieved when comparing the results of the road roughness map with the visual image,indicating the feasibility and effectiveness of the proposed framework.展开更多
A new method is presented for the segmentation of pulmonary parenchyma. The proposed method is based on the area calculation of different objects in the image. The main purpose of the proposed algorithm is the segment...A new method is presented for the segmentation of pulmonary parenchyma. The proposed method is based on the area calculation of different objects in the image. The main purpose of the proposed algorithm is the segment of the lungs images from the computer tomography(CT) images. The original image is binarized using the bit-plane slicing technique and among the different images the best binarized image is chosen. After binarization, the labeling is done and the area of each label is calculated from which the next level of binarized image is obtained. Then, the boundary tracing algorithm is applied to get another level of binarized image. The proposed method is able to extract lung region from the original images. The experimental results show the significance of the proposed method.展开更多
文摘针对库水位传统量测方法中水尺易锈蚀倾斜,精度低且成本高的问题,该文提出一种不依赖水尺,基于图像匹配的库水位变动识别方法。首先对监控相机拍摄的库坝上游面光学图像进行畸变消除和透视变换,消除相机误差。进一步选取包含水面的感兴趣区域(region of interest,ROI)图像进行自适应二值化分割、形态学处理等前处理操作,将水面和库坝特征分离,突出水位线位置。最后,利用归一化互相关匹配算法(normalised cross correlation,NCC)对水位变动前后的两幅图像进行匹配计算,识别水位线变动距离。通过室内试验与现场测试验证上述方法实用性。结果表明:基于图像匹配的库水位动态识别方法可准确识别水位变动,相对误差约为5%,此算法鲁棒性较高。该研究可为库水位自动化、低成本监测提供一种新思路。
基金Project(SIIT-AUN/SEED-Net-G-S1 Y16/018)supported by the Doctoral Asean University Network ProgramProject supported by the Metropolitan Expressway Co.,Ltd.,Japan+2 种基金Project supported by Elysium Co.Ltd.Project supported by Aero Asahi Corporation,Co.,Ltd.Project supported by the Expressway Authority of Thailand。
文摘This paper presents a voxel-based region growing method for automatic road surface extraction from mobile laser scanning point clouds in an expressway environment.The proposed method has three major steps:constructing a voxel model;extracting the road surface points by employing the voxel-based segmentation algorithm;refining the road boundary using the curb-based segmentation algorithm.To evaluate the accuracy of the proposed method,the two-point cloud datasets of two typical test sites in an expressway environment consisting of flat and bumpy surfaces with a high slope were used.The proposed algorithm extracted the road surface successfully with high accuracy.There was an average recall of 99.5%,the precision was 96.3%,and the F1 score was 97.9%.From the extracted road surface,a framework for the estimation of road roughness was proposed.Good agreement was achieved when comparing the results of the road roughness map with the visual image,indicating the feasibility and effectiveness of the proposed framework.
基金supported (in part) by research funding from Chosun University, Korea, 2013
文摘A new method is presented for the segmentation of pulmonary parenchyma. The proposed method is based on the area calculation of different objects in the image. The main purpose of the proposed algorithm is the segment of the lungs images from the computer tomography(CT) images. The original image is binarized using the bit-plane slicing technique and among the different images the best binarized image is chosen. After binarization, the labeling is done and the area of each label is calculated from which the next level of binarized image is obtained. Then, the boundary tracing algorithm is applied to get another level of binarized image. The proposed method is able to extract lung region from the original images. The experimental results show the significance of the proposed method.
