Sophie Lacherade

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This paper aims to link the spectral and directional variations of the leaf Bidirectional Reflectance Distribution Function (BRDF) by differentiating specular and diffuse components. To do this, BRDF of laurel (Prunus laurocesarus), European beech (Fagus silvatica) and hazel (Corylus avellana) leaves were measured at 400 wavelengths evenly spaced over the(More)
Radiometric cross calibration of Earth observation sensors is a crucial need to guarantee or quantify the consistency of measurements from different sensors. Twenty desert sites, historically selected, are revisited, and their radiometric profiles are described for the visible to the near-infrared spectral domain. Therefore, acquisitions by various sensors(More)
PLEIADES is the highest resolution civilian earth observing system ever developed in Europe. This imagery program is conducted by the French National Space Agency, CNES. It operates since 2012 a first satellite PLEIADES-HR launched on 2011 December 17th, a second one should be launched by the end of the year. Each satellite is designed to provide optical 70(More)
The first Pleiades-HR satellite, part of a constellation of two, has been launched on December 17, 2011. This satellite produces high resolution optical images. In order to achieve good image quality, Pleiades-HR should first undergo an important 6 month commissioning phase period. This phase consists in calibrating and assessing the radiometric and(More)
The availability of new very high spatial resolution sensors has for the past few years allowed a precise description of urban areas, and thus the settlement of specific ground or atmosphere characterization methods. However, in order to develop such techniques, a radiative transfer tool dedicated to such an area is necessary. AMARTIS v2 is a new radiative(More)
In partnership with the European Commission and in the frame of the Global Monitoring for Environment and Security (GMES) program, the European Space Agency (ESA) is developing the Sentinel-2 optical imaging mission devoted to the operational monitoring of land and coastal areas. The Sentinel-2 mission is based on a satellites constellation deployed in(More)
As the resolution of new earth observation sensors increases, a precise modeling of the signal is necessary for the urban medium. For very high spatial resolution, 3D structure and directional effects must be taken into account. This paper aims to estimate the contribution of the facades and the directional properties in the simulation of at sensor signals.(More)
The paper presents a new method of image simulation. More precisely, it focus on the most important step of this method. This step consists in retrieving reflectance composing an urban scene thanks to a set of multi-angular acquisitions. The high resolution of these acquisitions make the problem complex and the “flat ground” methods become(More)
A new permanently instrumented radiometric calibration site for high/medium resolution imaging satellite sensors is currently under development, focussing on the visible and near infra-red parts of the spectrum. The site will become a European contribution to the Committee on Earth Observation Satellites (CEOS) initiative RadCalNet (Radiometric Calibration(More)
Automatic mapping of urban materials from remotely sensed radiance images remains difficult because of the complex physical phenomena induced by relief. Indeed, shadows and environment effects disrupt the radiance incoming the sensor. Moreover, the measured radiance depends on the illumination conditions of the observed area. This is quite problematic for(More)
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