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The objective of this study was to compare the retrieval performances of several biophysical variables from the accumulation of large swath satellite data, the VEGETATION/SPOT4 sensor being taken as an example. This included leaf area index (LAI), fraction of photosynthetically active radiation (fAPAR) and chlorophyll content integrated over the canopy (C_ab·LAI), gap fraction in any direction [P₀(θ)], or in particular directions (nadir [P₀(0)], sun direction [P₀(θ_s)], or 58° [P₀(58°)] for which the gap fraction is theoretically independent of the LAI). A database of top of canopy BRDF (bidirectional reflectance distribution function) of homogeneous canopies was built using simulations by the SAIL, PROSPECT, and SOILSPECT radiative transfer models for a large range of input variables (LAI, mean leaf inclination angle, hot spot parameter, leaves and soil optical properties, date and latitude of observations) considering …