{"title":"Grids and Datums Update: This month we look at the Republic of Bénin","authors":"C. Mugnier","doi":"10.14358/pers.87.7.473","DOIUrl":"https://doi.org/10.14358/pers.87.7.473","url":null,"abstract":"","PeriodicalId":49702,"journal":{"name":"Photogrammetric Engineering and Remote Sensing","volume":"47 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2021-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82811378","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"GIS Tips & Tricks —When Out-of-the-Box Toolbars are Not Enough, Make Your Own","authors":"Kristopher Gallagher, A. Karlin","doi":"10.14358/PERS.87.6.323","DOIUrl":"https://doi.org/10.14358/PERS.87.6.323","url":null,"abstract":"","PeriodicalId":49702,"journal":{"name":"Photogrammetric Engineering and Remote Sensing","volume":"37 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2021-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76652002","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yihui Li, Gao Fang, Wentao Li, Zhang Peng, An Yuan, Zhong Xing, Zhai Yuwei, Yongjian Yang
{"title":"A High-Resolution Satellite DEM Filtering Method Assisted with Building Segmentation","authors":"Yihui Li, Gao Fang, Wentao Li, Zhang Peng, An Yuan, Zhong Xing, Zhai Yuwei, Yongjian Yang","doi":"10.14358/PERS.87.6.421","DOIUrl":"https://doi.org/10.14358/PERS.87.6.421","url":null,"abstract":"Digital elevation model (DEM) filtering is critical in DEM production, and large-area meter-level resolution DEM is mainly generated from high-resolution satellite images. However, the current DEM filtering methods are mostly aimed at laser scanning data and tend to excessively remove\u0000 ground points when processing a satellite digital surface model (DSM). To accurately filter out buildings and preserve terrain, we propose a DEM filtering algorithm using building segmentation results of orthophoto. Based on morphological filtering, our method estimates the probability of\u0000 being a built-up area or mountains for DSM, and according to this probability the filtering parameters are adaptively adjusted. For robustness, our method performs the above filtering operation on DSM through a sliding-window approach, and finally the nonground points are determined by the\u0000 votes of multiple filtering. Experiments against six representative data sets have shown that our method achieved superior perfor- mance than classical algorithms and commercial software.","PeriodicalId":49702,"journal":{"name":"Photogrammetric Engineering and Remote Sensing","volume":"87 1","pages":"421-430"},"PeriodicalIF":1.3,"publicationDate":"2021-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67146422","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Ecological Functions and Human Activity Interference Evaluation in Ecological Protection Redline for Urban Environment","authors":"Guo-ming Li, Binbin He, Liang Li, Miao Yang, Qiongyi Huang, Zihan Guo","doi":"10.14358/PERS.87.6.413","DOIUrl":"https://doi.org/10.14358/PERS.87.6.413","url":null,"abstract":"The influences of ecological protection redlines on urban sustainable development can significantly vary from place to place with distinct ecological functions and human activity interference. However, recent research lacks the evaluation of ecological functions and human activity interference\u0000 in ecological protection redline areas near urban areas. This article presents an evaluation method consisting of two evaluation criteria systems: an ecological function evaluation criteria system based on conserving water resources and soil and maintaining biodiversity and a human activity\u0000 interfer- ence evaluation criteria system based on the human activity impact index, population and road network density, and the intensity of tourism activity and livelihood sewage discharge. This evaluation method was verified in Zoige County, China, by using remote sensing data to evaluate\u0000 ecological functions and human activity interference in the ecological redline area for an urban environment. This evaluation method is one of the preliminary studies of urban sustainable develop- ment planning, and the result could provide a basis for the formulation of urban sustainable\u0000 development strategy.","PeriodicalId":49702,"journal":{"name":"Photogrammetric Engineering and Remote Sensing","volume":"87 1","pages":"413-420"},"PeriodicalIF":1.3,"publicationDate":"2021-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47744684","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A Combined Unmixing Framework for Impervious Surface Mapping on Medium-Resolution Images with Visible Shadows","authors":"Hui Luo, N. Chen","doi":"10.14358/PERS.87.6.431","DOIUrl":"https://doi.org/10.14358/PERS.87.6.431","url":null,"abstract":"Spectral unmixing methods with medium-resolution remote sensing images have become the main approach to mapping urban impervious-surface information. However, as more tall buildings appear, numerous visible shadows exist in medium-resolution images; these have usually been ignored in\u0000 previous research, but they seriously affect accuracy. To solve this problem, we propose a combined unmixing framework to extract impervious surface in nonshadow and shadow areas, using linear and nonlinear unmixing models, respectively. First shadow is separated from nonshadow. Then a nonlinear\u0000 unmixing method is selected to map impervious surface in shadow, which is more suitable to the complex imaging environment in shadow, and a classic linear unmixing model in nonshadow. Through experimental tests, the proposed combined unmixing framework is shown to effectively reduce error\u0000 in two study areas compared with classical unmixing methods.","PeriodicalId":49702,"journal":{"name":"Photogrammetric Engineering and Remote Sensing","volume":"87 1","pages":"431-443"},"PeriodicalIF":1.3,"publicationDate":"2021-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46426144","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"An Incremental Isomap Method for Hyperspectral Dimensionality Reduction and Classification","authors":"Yi Ma, Zezhong Zheng, Yutang Ma, Mingcang Zhu, Huang Ran, Xueye Chen, Qingjun Peng, Yong He, Yufeng Lu, G.M. Zhou, Zhigang Liu, Mujie Li","doi":"10.14358/PERS.87.7.445","DOIUrl":"https://doi.org/10.14358/PERS.87.7.445","url":null,"abstract":"Many manifold learning algorithms conduct an eigen vector analysis on a data-similarity matrix with a size of N×N, where N is the number of data points. Thus, the memory complexity of the analysis is no less than O(N2). We pres- ent in this article an incremental manifold\u0000 learning approach to handle large hyperspectral data sets for land use identification. In our method, the number of dimensions for the high-dimensional hyperspectral-image data set is obtained with the training data set. A local curvature varia- tion algorithm is utilized to sample a subset\u0000 of data points as landmarks. Then a manifold skeleton is identified based on the landmarks. Our method is validated on three AVIRIS hyperspectral data sets, outperforming the comparison algorithms with a k–nearest-neighbor classifier and achieving the second best performance with support\u0000 vector machine.","PeriodicalId":49702,"journal":{"name":"Photogrammetric Engineering and Remote Sensing","volume":"87 1","pages":"445-455"},"PeriodicalIF":1.3,"publicationDate":"2021-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47618403","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Qiutong Yu, Wei Liu, W. Gonçalves, J. M. Junior, Jonathan Li
{"title":"Spatial Resolution Enhancement for Large-Scale Land Cover Mapping via Weakly Supervised Deep Learning","authors":"Qiutong Yu, Wei Liu, W. Gonçalves, J. M. Junior, Jonathan Li","doi":"10.14358/PERS.87.6.405","DOIUrl":"https://doi.org/10.14358/PERS.87.6.405","url":null,"abstract":"Multispectral satellite imagery is the primary data source for monitoring land cover change and characterizing land cover globally. However, the consistency of land cover monitoring is limited by the spatial and temporal resolutions of the acquired satellite images. The public availability\u0000 of daily high-resolution images is still scarce. This paper aims to fill this gap by proposing a novel spatiotemporal fusion method to enhance daily low spatial resolution land cover mapping using a weakly supervised deep convolutional neural network. We merge Sentinel images and moderate\u0000 resolution imaging spectroradiometer (MODIS )-derived thematic land cover maps under the application background of massive remote sensing data and the large spatial resolution gaps between MODIS data and Sentinel images. The neural network training was conducted on the public data set SEN12MS,\u0000 while the validation and testing used ground truth data from the 2020 IEEE Geoscience and Remote Sensing Society data fusion contest. The proposed data fusion method shows that the synthesized land cover map has significantly higher spatial resolution than the corresponding MODIS-derived land\u0000 cover map. The ensemble approach can be implemented for generating high-resolution time series of satellite images by fusing fine images from Sentinel-1 and -2 and daily coarse images from MODIS.","PeriodicalId":49702,"journal":{"name":"Photogrammetric Engineering and Remote Sensing","volume":"28 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2021-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82202621","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Quality Assessment of Heterogeneous Training Data Sets for Classification of Urban Area with Landsat Imagery","authors":"N. Lyimo, Fang Luo, Q. Cheng, Hao Peng","doi":"10.14358/pers.87.5.339","DOIUrl":"https://doi.org/10.14358/pers.87.5.339","url":null,"abstract":"Quality assessment of training samples collected from heterogeneous sources has received little attention in the existing literature. Inspired by Euclidean spectral distance metrics, this article derives three quality measures for modeling uncertainty in spectral information of open-source\u0000 heterogeneous training samples for classification with Landsat imagery. We prepared eight test case data sets from volunteered geographic information and open government data sources to assess the proposed measures. The data sets have significant variations in quality, quantity, and data type.\u0000 A correlation analysis verifies that the proposed measures can successfully rank the quality of heterogeneous training data sets prior to the image classification task. In this era of big data, pre-classification quality assessment measures empower research scientists to select suitable data\u0000 sets for classification tasks from available open data sources. Research findings prove the versatility of the Euclidean spectral distance function to develop quality metrics for assessing open-source training data sets with varying characteristics for urban area classification.","PeriodicalId":49702,"journal":{"name":"Photogrammetric Engineering and Remote Sensing","volume":"7 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2021-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91299981","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
L. F. Castanheiro, A. Tommaselli, A. Berveglieri, M. B. Campos, José Marcato Junior
{"title":"Modeling Hyperhemispherical Points and Calibrating a Dual-Fish-Eye System for Close-Range Applications","authors":"L. F. Castanheiro, A. Tommaselli, A. Berveglieri, M. B. Campos, José Marcato Junior","doi":"10.14358/PERS.87.5.375","DOIUrl":"https://doi.org/10.14358/PERS.87.5.375","url":null,"abstract":"Omnidirectional systems composed of two hyperhemispherical lenses (dual-fish-eye systems) are gaining popularity, but only a few works have studied suitable models for hyperhemispherical lenses and dual-fish-eye calibration. In addition, the effects of using points in the hyperhemispherical\u0000 field of view in photogrammetric procedures have not been addressed. This article presents a comparative analysis of the fish-eye models (equidistant, equisolid-angle, stereographic, and orthogonal) for hyperhemispherical-lens and dual-fish-eye calibration techniques. The effects of adding\u0000 points beyond 180° field of view in dual-fish-eye calibration using stability constraints of relative orientation parameters are also assessed. The experiments were performed with the Ricoh Theta dual-fish-eye system, which is composed of fish-eye lenses with a field of view of approximately\u0000 190° each. The equisolid-angle model presented the best results in the simultaneous calibration experiments. An accuracy of approximately one pixel in the object space units was achieved, showing the potential of the proposed approach for close-range applications.","PeriodicalId":49702,"journal":{"name":"Photogrammetric Engineering and Remote Sensing","volume":"24 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2021-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74321911","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}