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The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences. Vol. XXXVII. Part Bl. Beijing 2008
«M
Along track GSD * 1 00478 m
U4
MF
Across track GSD = 1.00538 m
Figure 9. The result of GSD Check (3 deg Tilt)
• Fluctuation in MS2 & MS4
There is sometime a fluctuation of even and odd pixel in
MS2 and MS4 band. This has been removed by FFT
method.
Figure 10. MS4 band fluctuation in K2 MSC image (Left: Raw
image, Right: Restored image by FFT method)
3.2 Non-Uniformity Correction (NUC)
PAN1 PAN2 PAN4 PAN3 PAN 5 PAN6
Figure 11. Blue line is full raw PAN image at same radiance,
and Red line is full PAN image restored by NUC.
3.3 Butting zone
KOMPSAT-2 MSC PAN has three CCDs of 5200 pixels. There
are two butting zone between CCDs that decrease the brightness
gradually. We found out some non-linearity in the butting zone,
and developed three algorithms to reduce it; Scatter plot, BSM
(Butting zone Smoothing Method) and Dispersion method, (for
more detailed; Lee 2007)
Figure 12. Up: Raw K2 MSC image data, Bottom: Applied by
NUC
*'fixi. Uhm
Figure 13. Non-linearity in Butting zone
Figure 14. Up: The butting zone between PAN2 & PAN4,
Bottom: Corrected
3.4 MTF&MTFC
See the paper; Lee 2007
3.5 Geometric Cal/Val
See the paper; Seo 2007
4. CONCLUSION
For one-half year after KOMPSAT-2 launch, KARI Cal/Val
team has carried out the Calibration and Validation to guarantee
the image quality of KOMPSAT-2 MSC image data, so that the
Users can take the KOMPSAT-2 image data with good image
quality now. Nevertheless, there is much room for more
enhancements of the image quality of the KOMPSAT-2 image
data; MTFC, Reduce noise, Geo-accuracy, Band-to-Band
registration, Absolute radiometric calibration, Users Manual,
etc .
REFERENCE
Lee, D., 2008, Image Restoration of Calibration and Validation
for KOMPSAT-2, ISPRS2008
Seo, D., 2008, KOMPSAT-2 direct sensor modeling and
geometric calibration/validation, ISPRS2008
Ryan, R., 2003, Parameters Describing Earth Observing
Remote Sensing Systems, International workshop on
Radiometric and Geometric Calibration, USA
