to degraded accuracy of classification if the existing methods are applied. The
balanced selection depends on the classification tasks.
2. Preprocessing: The preprocessing includes geometric correction, radiometric
correction, and cloud masking. Geometric correction is the process of digitally
removing the geometric distortions to match a specific projected surface or shape
in digital image processing (JARS 1999; Toutin 2004; Mather and Koch 2011).
Geometric distortions are mainly coming from three sources: sensor (observer),
target (observed), and projection (reference) (JARS 1999; Toutin 2004; Mather
and Koch 2011). Most sensor-related distortions (variations in movement, attitude, mechanics, viewing angles, and clock) can be systematically corrected.
These are often done by data provider or satellite sensor-receiving stations. The
remaining distortions from the sensor (i.e., degrading, nonsystematic variations),
Fig. 10.1 General
workflow for crop pattern
mapping with remote
sensing
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