Difference between revisions of "Robin subwindow density/quality calculations"

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The ROBIN_CORRECTED_DENSITY and ROBIN_CORRECTED_QUALITY are calculated according to the following function :
  
−
Calculate density and quality parameter based on measurement conditions, i.e. influence of Robin
 
−
algoritme. Robin-algoritme is influencing density calculations when (1) bird density is high
 
−
(rain mask is removing birds), (2) birds fly in large flocks (rain mask is removing birds).
 
−
Rules have been designed and tested for Wier, Milligen and Glons to overcome the above problems
 
−
The quality parameter is decreasing from 1 (optimal functionality) to 0 (no radar video)
 
  
−
* land_cl_perc      Percentage landclutter in image
 
−
* rain_cl_perc      Percentage rainclutter in image
 
−
* total_mass_density Total mass per window before Robin processing
 
−
* land_mass_density  Total mass per window within the land clutter mask
 
−
* bird_echo_density  Calculated bird density per km2, taking measurement area into account (% clutter)
 
−
* echo_mass          Mean mass per bird echo (re-scaled number is bird_mass_density / bird_echo_density if bird_echo_density  > 0 and 0 otherwise)
 
−
* nr_of_tracks      Number of tracks in the whole image
 
−
* land_clutter_mode  Type of landclutter filtering
 
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* radar_name       
 
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* beam_name
 
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* window            Name of selected subwindow
 
  
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Normal clutter in a subwindow is assumed to be zero. This is not always true and is the reason
+
  sub Quantify_ROBIN
−
why rules are not appicable to all subwindows without modification. Therefore modus of standard clutter percentage is added for each subwindow to default clutPerc
+
  {
−
 
+
−
                NW      SE
+
    my ($whole_window, $sub_window, $correction_level, $radar_name, $beam_name, $window, $log) = @_;
−
GLONS_B1      15.05%  18.65%
+
    my $ROB_density = 0;
−
GLONS_B2        1.28%   5.33%
+
    my $ROB_quality = 0;
−
  RPN_B1          0.06%   0.07%
+
    my $ROB_cor_level = undef;
−
  RPN_B2          0.00%   0.00%
+
    my $ClutPerc = 25;
−
MIL_B1          0.00%   0.00%
+
−
MIL_B2          0.00%   0.00%
+
    my ($radar) = $radar_name =~ /RP-(\w{3})/;
 +
    my ($beam) = $beam_name =~ /BEAM_(\d+)/;
 +
    $beam = 'B' . $beam;
 +
    my $key = $radar . '_' . $beam . '_' . $window;
 +
   
 +
    my %DEFAULT_VALUES = (
 +
    GLO_B1_SE => { cthresh        => 1864,
 +
                  defReflectivity => 3033,
 +
                  defClut        => 18.65,
 +
                  CP              => 15
 +
                },
 +
    GLO_B1_NW => { cthresh        => 1864,
 +
                  defReflectivity => 901,
 +
                  defClut        => 15.05,
 +
                  CP              => 15
 +
                },
 +
    GLO_B2_SE => { cthresh        => 1804,
 +
                  defReflectivity => 527,
 +
                  defClut        => 3.33,
 +
                  CP              => 15
 +
                },
 +
    GLO_B2_NW => { cthresh        => 1804,
 +
                  defReflectivity => 44,
 +
                  defClut        => 1.28,
 +
                  CP              => 15
 +
                },
 +
 +
    WIE_B1_SE => { cthresh        => 310,
 +
                  defReflectivity => 0,
 +
                  defClut        => 0,
 +
                  CP              => 15
 +
                },
 +
    WIE_B1_NW => { cthresh        => 310,
 +
                  defReflectivity => 0,
 +
                  defClut        => 0,
 +
                  CP              => 15
 +
                },
 +
    WIE_B2_SE => { cthresh        => 594,
 +
                  defReflectivity => 0,
 +
                  defClut        => 0,
 +
                  CP              => 15
 +
                },
 +
    WIE_B2_NW => { cthresh        => 594,
 +
                  defReflectivity => 0,
 +
                  defClut        => 0,
 +
                  CP              => 15
 +
                },
 +
   );
 +
   
 +
  my $cthresh        = 0;
 +
  my $defReflectivity = 0;
 +
  my $defClut        = 0;
 +
  my $CP              = 0;
 +
 +
  if(exists($DEFAULT_VALUES{$key})) {
 +
    $cthresh        = $DEFAULT_VALUES{$key}->{cthresh};
 +
    $defReflectivity = $DEFAULT_VALUES{$key}->{defReflectivity};
 +
    $defClut        = $DEFAULT_VALUES{$key}->{defClut};
 +
    $CP              = $DEFAULT_VALUES{$key}->{CP};
 +
  }
 +
 +
  # Calculate echo mass. If subwindow is saturated, echo_mass is extracted
 +
   # from the whole window (radar.subwindow_result.subwindow_id = 0).
 +
 
 +
  my $echo_mass;
 +
  if($sub_window->{bird_echo_density} > 0) {
 +
    $echo_mass = $sub_window->{bird_mass_density} / $sub_window->{bird_echo_density};
 +
  } elsif($whole_window->{bird_echo_density} > 0) {
 +
    $echo_mass = $whole_window->{bird_mass_density} / $whole_window->{bird_echo_density};
 +
  } else {
 +
    $echo_mass = 400;
 +
  }
 +
   
 +
  # Calculate adjusted density (#/km²), quality parameter (0..1) and
 +
  # correction level for peak adjustments (1..3)
 +
  if ($whole_window->{total_mass_density} < 10 and
 +
      $whole_window->{land_cl_perc} == 0 and
 +
      $whole_window->{n} == 0)  {
 +
    # No data in image: total_mass<10, land_cl_perc=0, n=0
 +
    $ROB_density = undef;
 +
    $ROB_quality = 0;
 +
  } elsif($sub_window->{rain_cl_perc} == 100 and $sub_window->{land_cl_perc} == 100) {
 +
    $ROB_density = undef;
 +
    $ROB_quality = 0;
 +
  } elsif($correction_level > $cthresh) { # S/N ratio is above threshold, measurement removed
 +
    $ROB_density = undef;
 +
    $ROB_quality = 0;
 +
  } elsif ($sub_window->{rain_cl_perc} > 90 and
 +
          ($sub_window->{rain_cl_perc}-$sub_window->{land_cl_perc}) >= $CP and $echo_mass > 0) {
 +
    $ROB_density = ($sub_window->{total_mass_density} - $defReflectivity) / $echo_mass;
 +
    $ROB_quality = sqrt( (100 - $sub_window->{land_cl_perc}) / (100 - $defClut) );
 +
    $ROB_cor_level = 3;
 +
   } elsif ($sub_window->{rain_cl_perc}-$sub_window->{land_cl_perc} >= ($ClutPerc - $defClut) * 1.5 and $echo_mass > 0) {
 +
    $ROB_quality = (100 - $sub_window->{land_cl_perc}) / (100 - $defClut);
 +
    $ROB_density = ($sub_window->{total_mass_density} - $sub_window->{land_mass_density}) / $echo_mass;
 +
    if($ROB_quality > 0.8) {
 +
      $ROB_cor_level = 1;
 +
    } elsif($ROB_quality > 0.5) {
 +
      $ROB_cor_level = 2;
 +
    }
 +
   } elsif ($sub_window->{bird_echo_density} > 0.05 and $echo_mass > 800) {
 +
    $ROB_quality = sqrt((100 - $sub_window->{rain_cl_perc}) / (100 - $defClut));
 +
    $ROB_density = ($sub_window->{total_mass_density} - $sub_window->{land_mass_density}) / $echo_mass;
 +
    if($ROB_quality > 0.8) {
 +
      $ROB_cor_level = 1;
 +
    } elsif($ROB_quality > 0.5) {
 +
      $ROB_cor_level = 2;
 +
    }
 +
   } else {
 +
    $ROB_quality = sqrt((100 - $sub_window->{land_cl_perc}) / (100 - $defClut));
 +
    $ROB_density = $sub_window->{bird_echo_density};
 +
    if($ROB_quality > 0.8) {
 +
      $ROB_cor_level = 1;
 +
    } elsif($ROB_quality > 0.5) {
 +
      $ROB_cor_level = 2;
 +
    }
 +
  }
 +
  return ( $ROB_density, $ROB_quality, $ROB_cor_level);
 +
  }

Latest revision as of 11:15, 24 June 2009

The ROBIN_CORRECTED_DENSITY and ROBIN_CORRECTED_QUALITY are calculated according to the following function : 


 sub Quantify_ROBIN
 {

   my ($whole_window, $sub_window, $correction_level, $radar_name, $beam_name, $window, $log) = @_;
   my $ROB_density = 0;
   my $ROB_quality = 0;
   my $ROB_cor_level = undef;
   my $ClutPerc = 25;

   my ($radar) = $radar_name =~ /RP-(\w{3})/;
   my ($beam) = $beam_name =~ /BEAM_(\d+)/; 
   $beam = 'B' . $beam;
   my $key = $radar . '_' . $beam . '_' . $window;

   my %DEFAULT_VALUES = (
   GLO_B1_SE => { cthresh         => 1864,
                  defReflectivity => 3033,
                  defClut         => 18.65,
                  CP              => 15
                },
   GLO_B1_NW => { cthresh         => 1864,
                  defReflectivity => 901,
                  defClut         => 15.05,
                  CP              => 15
                },
   GLO_B2_SE => { cthresh         => 1804,
                  defReflectivity => 527,
                  defClut         => 3.33,
                  CP              => 15
                },
   GLO_B2_NW => { cthresh         => 1804,
                  defReflectivity => 44,
                  defClut         => 1.28,
                  CP              => 15
                },

   WIE_B1_SE => { cthresh         => 310,
                  defReflectivity => 0,
                  defClut         => 0,
                  CP              => 15
                },
   WIE_B1_NW => { cthresh         => 310,
                  defReflectivity => 0,
                  defClut         => 0,
                  CP              => 15
                },
   WIE_B2_SE => { cthresh         => 594,
                  defReflectivity => 0,
                  defClut         => 0,
                  CP              => 15
                },
   WIE_B2_NW => { cthresh         => 594,
                  defReflectivity => 0,
                  defClut         => 0,
                  CP              => 15
                },
 );

 my $cthresh         = 0;
 my $defReflectivity = 0;
 my $defClut         = 0;
 my $CP              = 0;

 if(exists($DEFAULT_VALUES{$key})) {
   $cthresh         = $DEFAULT_VALUES{$key}->{cthresh};
   $defReflectivity = $DEFAULT_VALUES{$key}->{defReflectivity};
   $defClut         = $DEFAULT_VALUES{$key}->{defClut};
   $CP              = $DEFAULT_VALUES{$key}->{CP};
 }

 # Calculate echo mass. If subwindow is saturated, echo_mass is extracted 
 # from the whole window (radar.subwindow_result.subwindow_id = 0).
  
 my $echo_mass;
 if($sub_window->{bird_echo_density} > 0) {
   $echo_mass = $sub_window->{bird_mass_density} / $sub_window->{bird_echo_density};
 } elsif($whole_window->{bird_echo_density} > 0) {
   $echo_mass = $whole_window->{bird_mass_density} / $whole_window->{bird_echo_density};
 } else {
   $echo_mass = 400;
 }

 # Calculate adjusted density (#/km²), quality parameter (0..1) and 
 # correction level for peak adjustments (1..3)
 if ($whole_window->{total_mass_density} < 10 and 
     $whole_window->{land_cl_perc} == 0 and 
     $whole_window->{n} == 0)  {
   # No data in image: total_mass<10, land_cl_perc=0, n=0
   $ROB_density = undef;
   $ROB_quality = 0;
 } elsif($sub_window->{rain_cl_perc} == 100 and $sub_window->{land_cl_perc} == 100) {
   $ROB_density = undef;
   $ROB_quality = 0;
 } elsif($correction_level > $cthresh) { # S/N ratio is above threshold, measurement removed
   $ROB_density = undef;
   $ROB_quality = 0;
 } elsif ($sub_window->{rain_cl_perc} > 90 and 
          ($sub_window->{rain_cl_perc}-$sub_window->{land_cl_perc}) >= $CP and $echo_mass > 0) {
   $ROB_density = ($sub_window->{total_mass_density} - $defReflectivity) / $echo_mass;
   $ROB_quality = sqrt( (100 - $sub_window->{land_cl_perc}) / (100 - $defClut) );
   $ROB_cor_level = 3;
 } elsif ($sub_window->{rain_cl_perc}-$sub_window->{land_cl_perc} >= ($ClutPerc - $defClut) * 1.5 and $echo_mass > 0) {
   $ROB_quality = (100 - $sub_window->{land_cl_perc}) / (100 - $defClut);
   $ROB_density = ($sub_window->{total_mass_density} - $sub_window->{land_mass_density}) / $echo_mass;
   if($ROB_quality > 0.8) {
     $ROB_cor_level = 1;
   } elsif($ROB_quality > 0.5) {
     $ROB_cor_level = 2;
   }
 } elsif ($sub_window->{bird_echo_density} > 0.05 and $echo_mass > 800) {
   $ROB_quality = sqrt((100 - $sub_window->{rain_cl_perc}) / (100 - $defClut));
   $ROB_density = ($sub_window->{total_mass_density} - $sub_window->{land_mass_density}) / $echo_mass;
   if($ROB_quality > 0.8) {
     $ROB_cor_level = 1;
   } elsif($ROB_quality > 0.5) {
     $ROB_cor_level = 2;
   }
 } else {
   $ROB_quality = sqrt((100 - $sub_window->{land_cl_perc}) / (100 - $defClut));
   $ROB_density = $sub_window->{bird_echo_density};
   if($ROB_quality > 0.8) {
     $ROB_cor_level = 1;
   } elsif($ROB_quality > 0.5) {
     $ROB_cor_level = 2;
   }
 }
 return ( $ROB_density, $ROB_quality, $ROB_cor_level);
 }
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