Clouds and Shades Correction?

[reseadmin]

DROACOR offers two options for correction of cloud shadows and shades:

Below-Cloud Acquisitions:
In the main reflectance processor, there's a cloud shading correction option. This is meant for imagery flown below clouds, i.e. the imagery has reduced illumination due to cloud coverage. The percentage of cloud cover is then estimated from image and a specific formulation of the radiative transfer is used for the reflectance retrieval. For series of data, one may also process cloudy and non-cloudy data stripes in one step by this option, using a 'relative' cloud shading estimate.

Variable Cloud Shades:
If only portions of the image stripes are affected by cloud shades, the shading can be corrected in the mosaicking step after reflectance retrieval. There, a relative brightness is first to be calcuated during the mosaicking, which afterwards can be used for deshading. This procedure is a semi-empirical approach and uses a continous scattering function for the correction of the cloud shades along the full spectrum.