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Cloud and its shadow
at Caicos Bank
Inter-band correlation is very strong.
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Glint and Cloud at Tarawa
part of the cloud has been added
to the scatter plot
Sea-surface glint,
and haze that surrounds the cloud,
seem to exhibit very similar correlation here,
as they both mostly tell us
about Mie scattering in the atmosphere.
They both may be removed
through the same "deglinting" process.
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Sea-surface glint
is fairly strong
in this wind-swept SPOT image
Inter-band correlation is reasonable.
Smoothing can greatly improve this correlation.
Deglinting at Tarawa removes
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specular reflection at the sea surface :
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the sky glint from the sky dome
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the sun glint from direct sun light
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isolated lumps of haze,
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and the haze that surrounds the clouds
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<== Here a rectangular window has been left untouched
in order to illustrate
the -E extraction window feature of 4SM.
Deglinting blandly transfers the noise
from the NIR band into other bands!
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Upper : modeling on raw data
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note the presence of a faint lump of haze
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and the corresponding artifact in the form of underestimated depth and bottom brightness
Deglinting at Caicos Bank
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Lower : modeling on deglinted data
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see how deglinting has removed the haze (while its shadow is still there)
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and the corresponding improvement in the final result
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Deglinting at Lee Stocking Island, Bahamas (Ikonos)
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CENTRAL : raw data
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BACKDROP : smoothed-deglinted data
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Deglinting at MahoneBay,
Nova Scottia, Canada (CASI)
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Sunglint affect this area.
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poor correlation between the Nir band ond other bands
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deglinting based on the red bands over this fairly deep area.
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Removing the sunglint also removes the skyglint.
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The profile compares
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RAW in blue
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DEGLINTED in red
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Smart-Smoothed in green
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FINAL in black
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Smart-Smoothing
preserves the edges
at MahoneBay, Nova Scottia, Canada (CASI)
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No sunglint here
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Smart-Smoothing preserves the edges of the dark and shallower patch
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The profile compares
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RAW in blue
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DEGLINTED in red
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Smart-Smoothed in green
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FINAL in black
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Deglinting of a CASI mosaic
at Gezirat Siyul Reef, Red Sea
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