1,895 Hits in 9.0 sec

An Analysis of Shadow Effects on Spectral Vegetation Indexes Using a Ground-Based Imaging Spectrometer

Lifu Zhang, Xuejian Sun, Taixia Wu, Hongming Zhang
2015 IEEE Geoscience and Remote Sensing Letters  
A ground-based imaging spectrometer brings a turning point to solve this problem as it can obtain both high spatial and high spectral resolutions to obtain feature and shadow images simultaneously.  ...  Shadows can lead to either a reduction in or a total loss of information in an image.  ...  An Analysis of Shadow Effects on Spectral Vegetation Indexes Using a Ground-Based Imaging Spectrometer Lifu Zhang, Senior Member, IEEE, Xuejian Sun, Taixia Wu, and Hongming Zhang Abstract-Sunlit vegetation  ... 
doi:10.1109/lgrs.2015.2450218 fatcat:d7gruvi3mzd73fbmglzwlp742e

Analysis of Vegetation Red Edge with Different Illuminated/Shaded Canopy Proportions and to Construct Normalized Difference Canopy Shadow Index

Xu, Tian, Tian, Xu, Tang
2019 Remote Sensing  
Combined with the bare soil index (BSI), NDCSI was applied for linear spectral mixture analysis (LSMA) using Sentinel-2 multispectral imaging.  ...  Therefore, we devised a new vegetation index named normalized difference canopy shadow index (NDCSI) using red edge's reflectance and the NDVI.  ...  Acknowledgments: We sincerely thank Huaifei Shen, Kaijian Xu and Shaofei Tang for work of ground data collection; and other members of the Hyperspectral program of International Institute for Earth System  ... 
doi:10.3390/rs11101192 fatcat:jkjzmpo5xjbxvilgzzqysvdwxe

HySenS data exploitation for urban land cover analysis

G. Jones, E. S. Malinverni, A. Galli, G. Wilkinson, J. A. Benediktsson, F. Zucca, V. Casella, P. Gamba, F. Dell'Acqua, D. Greenhill
2006 Annals of Geophysics  
Here we show results referring to an accurate characterization and classification of land cover/use, using different supervised approaches, exploiting spectral as well as spatial information.  ...  During the project we collected DAIS and ROSIS data over the urban test area of Pavia, Northern Italy, though due to a late delivery of ROSIS data only DAIS data was used in this work.  ...  Acknowledgements The authors wish to thank the DLR for performing the campaign and providing the data within the framework of the HySenS project and the CNR for collecting the ground reflectance data and  ... 
doi:10.4401/ag-3160 doaj:b1847a4c1eaf4d36b5f6b9e931b8c2b5 fatcat:5mkdfiks6fdtjgbypjfymx3fha


J. M. Landmann, M. Rutzinger, M. Bremer, K. chmidtner
2016 The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences  
In the main step, spectral unmixing of the OLI images is applied to the larch forest, specifying the larch tree spectral signal based on corrected field spectrometer measurements of the larch understory  ...  In the case of vegetation, shadow effects on reflectance are especially difficult to determine. This work analyzes a larch forest stand (<i>Larix decidua</i> MILL.) in Pinnis Valley (Tyrol, Austria).  ...  The main goal is to extract the larch tree spectral signal in Landsat 8 (LS8) Operational Land Imager (OLI) visible and Near-Infrared (NIR) surface reflectance channels, using combined ground-and satellite-based  ... 
doi:10.5194/isprs-archives-xli-b7-671-2016 fatcat:bkq4zryolfdfjg4qcsmyqexbti

Spectrodirectional remote sensing for the improved estimation of biophysical and -chemical variables: two case studies

Michael E. Schaepman, Benjamin Koetz, Gabriela Schaepman-Strub, Klaus I. Itten
2005 International Journal of Applied Earth Observation and Geoinformation  
In the second case study, we acquired spectrodirectional data on ground using a field goniometer in parallel with several HyMap imaging spectrometer overflights.  ...  We describe the soil-vegetation-atmosphere radiative transfer using a combination of the PROSPECT, GeoSAIL, and ATCOR models.  ...  In the second case study, we are discussing ground based directional measurements as well as directional data acquisition using a complex flight pattern for an airborne imaging spectrometer. 2.  ... 
doi:10.1016/j.jag.2004.10.012 fatcat:ps2l7352l5hsvaadetda6z3yvi

An Unsupervised Classification Method for Hyperspectral Remote Sensing Image Based on Spectral Data Mining [chapter]

Xingping Wen, Xiaofeng Yang
2012 Advances in Data Mining Knowledge Discovery and Applications  
U1133602), China Postdoctoral Science Foundation (20100471687) and the innovation team of ore-forming dynamics and prediction of concealed deposits, Kunming University of Science and Technology, Kunming  ...  Acknowledgement This study was jointly supported by Natural Science Foundation of China (Grant No. 41101343), Natural Science Foundation of China (Grant No.  ...  It can effectively extract low reflectivity ground objects such as water or vegetation in shadowed area from hyperspectral remote sensing data using spectral data mining.  ... 
doi:10.5772/50135 fatcat:ykkbqvrf6jebhjcrkumxriikwy

Cast Shadow Detection to Quantify the Aerosol Optical Thickness for Atmospheric Correction of High Spatial Resolution Optical Imagery

Daniel Schläpfer, Andreas Hueni, Rudolf Richter
2018 Remote Sensing  
In a first step, a novel spectral cast shadow detection algorithm determines the shadow areas using spectral indices.  ...  Evaluation of the cast shadow masks shows an overall classification accuracy on an 80% level.  ...  The Remote Sensing Laboratories of the University of Zurich (RSL) are thanked for providing the APEX data, and the support of Hendrik Wulf from RSL with the ASD ground reference measurements is gratefully  ... 
doi:10.3390/rs10020200 fatcat:x7dey3poanepfnv77hyspudr2a

Unmanned aerial vehicle (UAV) hyperspectral remote sensing for dryland vegetation monitoring

Jessica J. Mitchell, Nancy F. Glenn, Matthew O. Anderson, Ryan C. Hruska, Anne Halford, Charlie Baun, Nick Nydegger
2012 2012 4th Workshop on Hyperspectral Image and Signal Processing (WHISPERS)  
the influence of altitude on geometric error, image mosaicking, and dryland vegetation classification.  ...  Future mapping efforts that leverage ground reference data, ultra-high spatial resolution photos and time series analysis should be able to effectively distinguish native grasses such as Sandberg bluegrass  ...  The complete UAV-based hyperspectral collection system consists of a PIKA II imaging spectrometer and P-CAQ airborne data acquisition unit (Resonon, Inc., Bozeman, MT); a Piccolo II autopilot (Cloud Cap  ... 
doi:10.1109/whispers.2012.6874315 dblp:conf/whispers/MitchellGAHHBN12 fatcat:bd6vrmea4bf3thvd53i344diby

Inversion of Nitrogen Concentration in Apple Canopy Based on UAV Hyperspectral Images

Wei Li, Xicun Zhu, Xinyang Yu, Meixuan Li, Xiaoying Tang, Jie Zhang, Yuliang Xue, Canting Zhang, Yuanmao Jiang
2022 Sensors  
A Cubert UHD185 imaging spectrometer mounted on a UAV was used to obtain the hyperspectral images of the apple canopy.  ...  This study strived to explore an effective approach for inversing and mapping the distributions of the canopy nitrogen concentration (CNC) based on Unmanned Aerial Vehicle (UAV) hyperspectral image data  ...  Acknowledgments: We would like to thank the kind help of the editor and the reviewers to improve the manuscript. Conflicts of Interest: The authors declare no conflict of interest.  ... 
doi:10.3390/s22093503 fatcat:hfw6iyc4cbalne37bssujuvs2e

Leaf Area Index Estimation Using MESMA Based on EO-1 Hyperion Satellite Imagery

Zhaoming Zhang
2014 International Journal of Information and Electronics Engineering  
Traditionally, remote sensing based techniques to estimate LAI have either been based on the empirical-statistical approach that relates ground-measured LAI to the spectral vegetation indices, or on a  ...  Multiple endmember spectral mixture analysis (MESMA) is an important one in the newly developed LAI retrieval methods.  ...  Generate spectral libraries using image spectra extracted from one or more Regions of Interest (ROIs) in an image.  ... 
doi:10.7763/ijiee.2014.v4.399 fatcat:pp3f472dxjbl7pdcx5so3d5vxu

A Neural Network Method for Classification of Sunlit and Shaded Components of Wheat Canopies in the Field Using High-Resolution Hyperspectral Imagery

Pouria Sadeghi-Tehran, Nicolas Virlet, Malcolm J. Hawkesford
2021 Remote Sensing  
of canopy biophysical and chemical characteristics. (2) Method: This study reports the development of a computer vision pipeline to analyze ground-acquired imaging spectrometry with high spatial and spectral  ...  The work focuses on the critical steps in the image analysis pipeline from pre-processing to the classification of hyperspectral images.  ...  Conflicts of Interest: The authors declare no conflict of interest.  ... 
doi:10.3390/rs13050898 fatcat:henfwag4d5gifalkm62dxpkloq

The behaviour of snow and snow-free surface reflectance in boreal forests: Implications to the performance of snow covered area monitoring

Miia Salminen, Jouni Pulliainen, Sari Metsämäki, Anna Kontu, Hanne Suokanerva
2009 Remote Sensing of Environment  
Based on the inversibility of the SCAmod reflectance model, we addressed the standard deviation (standard error) of SCA estimation contributed by wet snow and snow-free ground reflectance fluctuations.  ...  An average error in the determination of the fractional Snow Covered Area (SCA) of about 5-7 %-units was obtained (range from 0% = snow-free ground to 100% = full snow cover), the maximum error of 10-12  ...  Acknowledgements This work has been supported by the SNOW-CLIM (Snow Mapping of Boreal and Sub-Arctic Zones: Earth Observation Data-Based Multi-Source Information Systems and Application to Climatic Studies  ... 
doi:10.1016/j.rse.2008.12.008 fatcat:wi5apa5xgnekzf5ztwk6e3chau

Invasive species detection in Hawaiian rainforests using airborne imaging spectroscopy and LiDAR

Gregory P. Asner, David E. Knapp, Ty Kennedy-Bowdoin, Matthew O. Jones, Roberta E. Martin, Joseph Boardman, R. Flint Hughes
2008 Remote Sensing of Environment  
In Hawaiian forests, we recently found that invasive trees often have hyperspectral signatures unique from that of native trees, but mapping based on spectral reflectance properties alone is confounded  ...  The remaining sunlit canopy spectra were analyzed using spatially-constrained spectral mixture analysis.  ...  National Park Service and the State of Hawaii Division of Forestry and Wildlife.  ... 
doi:10.1016/j.rse.2007.11.016 fatcat:chqk5xdoojg4tlxwpvwkkck5bm

River Floodplain Vegetation Scenario Development Using Imaging Spectroscopy Derived Products as Input Variables in a Dynamic Vegetation Model

M.E. Schaepman, G.W.W. Wamelink, H.F. van Dobben, M. Gloor, G. Schaepman-Strub, L. Kooistra, J.G.P.W. Clevers, A. Schmidt, F. Berendse
2007 Photogrammetric Engineering and Remote Sensing  
In this contribution, we are linking imaging spectrometer derived products with a dynamic vegetation model to improve the simulation and evaluation of scenarios for a river floodplain in the Netherlands  ...  In particular, we are using airborne HyMap imaging spectrometer data to derive Leaf Area Index (LAI), spatial distribution of Plant Functional Types (PFT), and model dominant species abundances as input  ...  The contribution of G. Schaepman-Strub is supported by an European Space Agency (ESA) external fellowship. We thank the reviewers for their substantial comments.  ... 
doi:10.14358/pers.73.10.1179 fatcat:ouiz3oicq5dvfko7feiuhijmjq

Evaluation of hyperspectral data for pasture estimate in the Brazilian Amazon using field and imaging spectrometers

2008 Remote Sensing of Environment  
Using a field spectrometer, ten remotely sensed measurements (i.e., two vegetation indices, four fractions of spectral mixture analysis, and four spectral absorption features) were generated for two grass  ...  These results suggest possible improvements on estimating grass measures using spectral absorption features derived from hyperspectral sensors.  ...  We acknowledge JPL-NASA for loaning the ASD field spectrometer for our field survey. We also greatly thank Francisco Leonidas from EMBRAPA-CPAFRO, Fernando R.  ... 
doi:10.1016/j.rse.2007.08.014 fatcat:wp7i45fwwbgatcseqhzxhq3qx4
« Previous Showing results 1 — 15 out of 1,895 results