ted sky pixels.
een aggregated
d.
à Sun direction
ES
A
[ Environment maps | Lscan (A) | f ont) ]
Aggregated 1512 878
Perez 1230 7722
Corrected and aggr. 1558 896
Figure 9: Comparison of the simulated radiance with different
estimated environment maps. The radiance unit is arbitrary.
using an estimated parametric model of blue sky for computing
per-image corrections is proposed and reduces slightly the visual
artifacts. Anyway, the influence of the errors of the environment
map are small on the total simulated signal.
The detection of sky pixels with colorimetric thresholds is not
perfect; it could be enhanced by using LIDAR data when they
are available with the acquired images, or simply by using a 3D
model and a tree detection. Another interesting improvement
could come from exposure bracketing: the overexposed areas
would be reduced, and the artifacts could me more easily avoided
as they depend on the exposure.
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