Optical calibration, bathymetry, water column correction and bottom typing of shallow marine areas, using passive remote sensing imageries
WorldView 2 image at Waimanalo Beach, Oahu, Hawaii islands
3289x3241, 2 m ground resolution, courtesy of Ron Abileah

home

Using Ron's deglinted image
 
 


July 5th
Final results using Ron's deglinted image

Please download the following

  • 3289_rows by 3241_lines

  • raw rasters

  • without header

  • either U8, or S16, or U16

So that you can produce your own seatruth comparisons and illustrations.

You get my 4SM-deglinted version of Ron's deglinted spectral image:

  • U16, NO smoothing at all

  • Using my new deglinted version of Ron's deglinted image yields distinctly better results

  • Can you further "clean" your own version, or my new version, by some math gimmick?

  • What's the commercial potential?


Now I need to finalize the use of Stumpf's method.

 
  •  
 



Final computed depth ZC



SHOALS Lidar DTM


ZC-ZR
using bands 1, 2, 3, 4 and 5
with strong thresholds on bands 4 and 5
Tide correction applied: 1.00 m

  • blue tones for depth underestimated

  • red tones for depth overestimated


all wavelengths at mid-waveband

-cWL/0.500/0.500/0.500/0.500/0.500/0.500/0.500/0.500
-M/@001/@002/0003/004/005/@006/@007/008
-Lm/0001.0/001.0/001.0/010.0/010.0/010.0/255.0/255.0
-KK2_3_0.3500/Knir8.0/Bm400_BG510_GR628_RN700/mask_3
-Z/LAT1.00/N_2/land_2.0001/YXgreen025_022/z21/cZ1.00
-Smooth/5
/D/smart+

83.5% of computed depths
are within  +-2.0 m of DTM depth


ZC vs ZR regression
 

Depths computed based on

  • red       band 5, 4, 3, 2, 1

    • note the vgery severe threshold

  • yellow bands 4, 3, 2, 1

    • note the very severe threshold

  • green   bands 3, 2, 1

ZZRegressor: Statistics of seatruth ZC-ZR
on image waimanalowv2m_deg at Oahu, Hawaii
N=5.609 millions pixels by Morel's 4SM method
stepDTM=1 Smooth=1_5 Using_bands_1_2_3_4_5 cZ=1.00

 1.79% pixels with depth underestimated by more than 5.0 m
 4.17% pixels with depth underestimated by more than 3.0 m
 6.78% pixels with depth underestimated by more than 2.0 m
13.71% pixels with depth underestimated by more than 1.0 m
35.68% pixels with depth underestimated by more than 0.0 m
25.91% pixels with depth  overestimated by less than 1.0 m
 8.15% pixels with depth  overestimated by less than 2.0 m
 2.27% pixels with depth  overestimated by less than 3.0 m
 1.16% pixels with depth  overestimated by less than 5.0 m
 0.37% pixels with depth  overestimated by more than 5.0 m

61.60% of computed depths are within  +-1.0 m of DTM depth
83.46% of computed depths are within  +-2.0 m of DTM depth
92.51% of computed depths are within  +-3.0 m of DTM depth
97.83% of computed depths are within  +-5.0 m of DTM depth
over a total of 100.00% of computed depths

Ron's deglinted image further Deglinted
Color composite bands 2, 3 and 4

Water column corrected CC bands 2, 3 and 4

Profile Yellow
from South to North

  • section D runs through polluted waters at 1.2 km and also from 2.1 to 3 km

  • section C runs through polluted waters from 1.8 to 2.6 km

  • section B is entirely in clear waters

  • section A runs in polluted waters from 2.7 to 3.6 km

Profile Blue
from East to West

  • section E is in polluted waters from 1.1 to 2.4 km

    • only some towering coral patches are seen to emerge above a layer of polluted waters from 1.3 to 1.5 km

  • section D  crosses polluted waters from 1.5 to 1.8 km

  • section C is in polluted waters from 0 to 1.7 km

  • section B is entirely in clear waters

  • section A is entirely in clear waters




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