Syntax_Smooth
Specify conditions for smoothing
HowTo Smooth Plain
HowTo Smooth Smart

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Syntax_Smooth
Specify conditions for smoothing    
HowTo Smooth Plain
HowTo Smooth Smart
  • -S(s)mooth_2D(d)/S(s)mart+(-)
  • -Smooth_5d/Smart+
  • NO SMOOTHING
    • -smooth with a lowercase s..............Smoothing is disabled altogether
  • SMOOTHING
    • -Smooth with an uppercase S.............Smoothing is enabled
      • Smooth_N................................Maximum radius N of smoothing kernel
      • N must be <==5
    • -Smooth_ND............................ SmoothDeep=1
      • enable Smoothing of Optically_Deep_Waters_masked at 240
    • Smooth_Nd.............................SmoothDeep=0
      • disable Smoothing of Optically_Deep_Waters_masked at 240
  • PLAIN SMOOTHING
    • smart with a lowercase s, SmartSmoothing is disabled altogether
      • plain smoothing shall apply
  • SMART SMOOTHING
    • Smart with a uppercase S..........SmartSmoothing is enabled
    • Smart+............................Smart smoothing enabled, SmoothPlus=1:
      • Forces a minimum N=1 smoothing kernel for all bright shallow pixels
    • Smart-.............................Smart smoothing disabled, SmoothPlus=0:
      • No smoothing of bright shallow pixels
  • Radiometric Noise (not compulsory, defaults to 1.00)
    • Smart+1.25..........radiometric Noise is set at 1.25
    • Smart+1.75..........radiometric Noise is set at 1.75
    • noise must be set >=1.0
    • for high noise level, increase from 1.00 up, see the results
    • this is used in SmartSmoothing to specify the radius of the smart smoothing window
IMPORTANT NOTES
  • CUT LINE..........smoothing does not mix Flight_numbers: no smoothing across the mosaicking_cutline
  • WATER LINE.....smoothing does not mix shallow pixels and dryland pixels: no smoothing across the waterline
  • mSE....................smoothing does not mix mSE values of shallow pixels
    • only pixels with same mSE values contribute to the smoothing of the current pixel



 


How to Smooh_Plaint
Syntax Smooth
  • Plain smoothing applies a circular smoothing window
  • Radius of smoothing window is in the range from 1 to 5 pixels
    • ?this achieves 3*3, 5*5, 7*7, 9*9 and 11*11 circular smoothing window
  • SmoothDeep
    • ?enable argument D(d) to smooth optically deep waters if desired.
  • No smoothing across the waterline, No smoothing is applied over dry land
  • The radius of the smoothing window is written in image WR
  

How to Smooth_Smart
Syntax Smooth

 
  • Smart_Smoothing is needed over shallow areas
  • Dual purpose
    • apply a wider smoothing geometric window to darker pixels, and vice versa in order to smooth more efficiently darker pixels
    • select pixels within a limited radiance window for computing an averaged spectral radiance in an attempt to preserve edges
  • The Syntax_is -S(s)mooth_N/D(d)/S(s)mart+(-)
    • S(s)mooth.........enable(disable) Smoothing
    • D(d)................... enable(disable) SmoothDeep to smooth optically deep waters if desired
    • S(s)mart...........enable(disable) Smart_Smoothing
  • SmartPlus
    • if SmartPlus is at +
      • above a certain brightness, all shallow pixels to be smoothed by a 3*3 window
    • if SmartPlus is at -
      • no smoothing is applied to pixels above a certain brightness,
      • while smart-smoothing is applied to deeper/darker pixels
  • No smoothing across the waterline, No smoothing is applied over dry land
 
image_WR
  • The radius of the smoothing window is written in image WR
Edge-preserving smoothing :
the N variable  in -Smooth_N/D/Smart+ is used to customize the window radius for each shallow pixel as follows:
  • Can take values in the range of 1 to 5.
  • A rather complicated and confuse scheme, still under development: please experiment for yourself.
  • Within the resulting circular window, only pixels with a radiance inside a certain tolerance range shall contribute to the smoothing: others are bypassed.
    • therefore, if a pixel is dark, only some dark pixels inside the circular smoothing window shall contribute to the computation of smoothed radiance for that pixel.
    • therefore, if a pixel is bright, only some bright pixels inside the circular smoothing window shall contribute to the computation of smoothed radiance for that pixel.
  • As a result, sharp spatial contrast in the raw image shall hopefully remain sharp in the smoothed image.
  • It is necessary to experiment, in order to find a combination of the M and N variables that suits the image brightness and your particular expectations.



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