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Leaf area index retrieval study with a modelling framework, hemispherical photography and LiDARs
2014 IEEE Geoscience and Remote Sensing Symposium, 2014The availability of experimental data from forest sites, such as foliage density, is limited and is also subject to measurement errors. To address this problem, we designed a study around the use of a modeling framework of virtual forest stands with known architectural attributes using the freeware POV-Ray [1].
Sylvain G. Leblanc, Richard A. Fournier
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Hemispherical Photography in Support of Forest Inventory and Silviculture
2017Hemispherical photography (HP) can be used in support of silviculture and forest inventory. At the tree level, HP can be used to estimate attributes such as tree architecture, crown dimensions, and volume of standing trees. At the stand level, there are relationships between indices extracted from HP and stand attributes such as density, basal area ...
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Canopy Architectural Models in Support of Methods Using Hemispherical Photography
2017One of the most important limitations regarding the in situ measurement of forest canopies is the relative lack of knowledge of canopy structure. Yet the three-dimensional (3D) arrangement of canopy components is difficult to measure because of the significant spatial and temporal heterogeneity of canopy structure over a wide range of scales.
Jean-François Côté +2 more
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Agricultural and Forest Meteorology, 2013
Abstract Rapid, reliable and meaningful estimates of forest canopy are essential to the characterization of forest ecosystems. In this paper the accuracy of digital hemispherical (DHP) and cover (DCP) photography for the estimation of canopy properties in deciduous forests was evaluated.
Francesco Chianucci, Andrea Cutini
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Abstract Rapid, reliable and meaningful estimates of forest canopy are essential to the characterization of forest ecosystems. In this paper the accuracy of digital hemispherical (DHP) and cover (DCP) photography for the estimation of canopy properties in deciduous forests was evaluated.
Francesco Chianucci, Andrea Cutini
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Comparison of Image Segmentation Methods Based on Digital Hemisphere Photography
IGARSS 2023 - 2023 IEEE International Geoscience and Remote Sensing Symposium, 2023Tianxin Duan +5 more
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Primary results of using hemispherical photography for advanced GPS mission planning
The 9th International Conference "Environmental Engineering 2014", 2014This paper presents a preliminary results of using hemispherical digital photography obtained from fish-eye lens for advanced GPS mission planning. Nowadays, reach GPS constellation ensure availability of 3 dimensional position, anytime, anywhere over the world, except, where the obstructions prevent signal receiving occur.
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Relative radiance measurements and zenith angle dependent segmentation in hemispherical photography
Agricultural and Forest Meteorology, 2001Abstract When analysing hemispherical photographs taken from forest stands the grey value of the smallest picture unit — so-called ‘pixel’ — is taken as a measure of transmissivity. This derived information of transmission is based on the grey value of unobscured pixels which serves as a reference value. However, a particular grey value of unobscured
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MEF-DHP: Digital Hemispheric Photography Method Based On Multi-Exposure Fusion
IGARSS 2023 - 2023 IEEE International Geoscience and Remote Sensing Symposium, 2023Shuaifeng Jiao +6 more
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Hacquetia, 2003
Hemispherical (or fisheye) photography has wide applicability in various environmental monitoring, modelling and research. Since understory light conditions are very important determinant of vegetation pattern, during extensive field survey in dinaric part of the silver fir - beech forest areal, hemispherical photographs of forest canopy were taken at ...
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Hemispherical (or fisheye) photography has wide applicability in various environmental monitoring, modelling and research. Since understory light conditions are very important determinant of vegetation pattern, during extensive field survey in dinaric part of the silver fir - beech forest areal, hemispherical photographs of forest canopy were taken at ...
openaire +2 more sources