Arcachon tutorial: Modeling 2
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Model2_2
#Line_6 Model 2+++++++++++ Model 2+++++++++++ Model 2+++++++++++
nice -20  ./4SM.4.08 -Process/14_Jul_2011/06_JUL_2011  -OriginSPT @@
-DB/arcachon/27_1_0_0/3_1/500_630/0.010_22.610/1_1 @@
-Mis/Arcachon/France/Spot/XS/NA/UTM_1_008/0.020_0.020/1_AUG_1986 @@
-LS/0255.0/255.0/255.0 @@
-M/@000001/00002/00003 @@
-LsM/078.8/071.2/065.2_cLM=0.450 @@
-Lsw/030.4/014.2/008.0 @@
-Lw/0002.5/000.0/000.0 @@
-Lm/0001.0/001.0/255.0 @@
-KK1_2_0.42/Knir4.500/mask_1 @@
-Z/MSL0.00/cZ1.000 @@
-B/tclNe/LBref200_100/Bmin100/cLM1.00 @@
@Extract/v/mBPL2 @@
@Calibrate/v/BdSNpzg/BDh_12_13 @@
-Model/mask_2 @@
-smooth/5/D/Smart+ @@
@Recode/201_InChannel_9_into_233_OutChannel_4
 

B
Z is mapped to a maximum of 9.7 m
One-band case using LBref

Let's enable the "one-band case" for all pixels
  • which have been ousted
  • and have sufficient bottom contrast
  • Lsgreen-Lswgreen>=Lmgreen
Change for the following
  • -M0000001/00002/00003
  • -Lm/0001.0/001.0/255.0
  • -B/tclNe/Bmin100/LBref130_100/cLM1.00
Find your prefered values for
  • Lmgreen=1.0 : we might want to incerase this value
  • LBref[1]=130 : we might want to increase this value

Z is mapped 
to a maximum of 9.7 m

 


 How does the "one band case" work?
  • Shallow pixels which yield wZ=2 and B<130 are deemed foul in this environment
  • Those which satisfy Ls-Lsw>Lm (bottom contrast) qualify for the "one band case"
  • Depth for the one-band case is computed by
    • Z=(ln(LBref-Lw) - ln(Ls-Lsw))/K
    • Z=(ln(130    -2.5) - ln(Ls-30.4))/0.389
Thresholds must be increased,
in order to preclude
the most obviously foul water plumes
from showing off
 
Try the following NOW:
  • -Lm/0004.0/002.0/255.0           
  • -B/tclNe/Bmin110/LBref135_100/cLM1.00   
 
Can we trust this result?
  • YES for strong radiances Ls
    • Kred and Kgreen are quite trustworthy for a SPOT image
    • the "exponential decay" is well established
    • the "bottom contrast" Ls-Lsw is poorly affected by the uncertainty on Lsw
  • NO for weaker radiances Ls: bottom contrast is ,2.0 (see below)
    • Deeper than ~2 meters, areas of foul waters populate the output with foul results
      • least with a blue band,
      • more so with a green band,
      • even more so for the red bandand much more so for the NIR band
    • This is because of the diffuse properties of the underwater lightfield


 

Model2_3
Final Modeling
Thresholds must be increased,  in order to preclude
the most obvious remaining foul water plumes from showing off 
(some shall still remain though)

Try
  • -Lm/0004.0/002.0/255.0           
  • -B/tclNe/Bmin110/LBref135_100/cLM1.00   
Final command line
 
#Line_7 Model 2+++++++++++ Model 2+++++++++++ Model 2+++++++++++
nice -20  ./4SM.4.08 -Process/14_Jul_2011/06_JUL_2011  -OriginSPT @@
-DB/arcachon/27_1_0_0/3_1/500_630/0.010_22.610/1_1 @@
-Mis/Arcachon/France/Spot/XS/NA/UTM_1_008/0.020_0.020/1_AUG_1986 @@
-LS/0255.0/255.0/255.0 @@
-M/000001/00002/00003 @@
-LsM/078.8/071.2/065.2_cLM=0.450 @@
-Lsw/030.4/014.2/008.0 @@
-Lw/0002.5/000.0/000.0 @@
-Lm/0004.0/002.0/255.0 @@
-KK1_2_0.42/Knir4.500/mask_1 @@
-Z/MSL0.00/cZ1.000 @@
-B/tclNe/Bmin110/LBref135_100/cLM1.00 @@
@Extract/v/mBPL2 @@
@Calibrate/v/BdSNpzg/BDh_12_13 @@
-Model/mask_2 @@
-Smooth/5/D/Smart+ @@
@Recode/201_InChannel_9_into_233_OutChannel_4
 
 

Final depth
Z is mapped to a maximum of 5.7 m

FCC

Previous B
Z is mapped to a maximum of 9.7 m

Final B
Z is mapped to a maximum of 5.7 m
 


 



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