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GEMPAK LUTFIL vs McIDAS ET file

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  • Subject: GEMPAK LUTFIL vs McIDAS ET file
  • Date: Mon, 4 Mar 2002 13:23:55 -0500 (EST)
Hi everyone,

I try to match an enhancement table I have for Water Vapor Imagery. I created it
successfully in McIDAS:

 Brightness  Blue      Green      Red
  min max   min max   min max   min max
  --- ---   --- ---   --- ---   --- ---
    0 136     0   0     0   0     0   0
  137 205   165 255     0 255     0 255
  206 255   255 255   255 255   255 255

I tried to create a LUTFIL for GEMPAK that exhibits the same enhancement without
any success.

Is there a way to match a McIDAS enhancement table to a GEMPAK LUTFIL?

Best regards,

Christian Page
address@hidden    http://meteocentre.com/

Agent de recherche et de planification +1 514 987 3000 ext. 2376
Departement des Sciences de la Terre et de l'Atmosphere UQAM


>From address@hidden Mon Mar  4 12:32:23 2002
>To: Christian Page <address@hidden>
>cc: <address@hidden>, <address@hidden>,
>   <address@hidden>
>Subject: Re: GEMPAK LUTFIL vs McIDAS ET file

Christian,

I've had success with the attached PERL code.  In my experience, I've had
to use 128 colors instead of the full 256.  Also, be sure to enter in RED,
GREEN, BLUE order (the standard) not the crazy BLUE, GREEN, RED order of
Mcidas.  The following input for make_sat_enhancement.pl produced
the same enhancement in GEMPAK as yours did in Mcidas for me:
  128
  1,0,0,0
  68,0,0,0
  69,0,0,165
  102,255,255,255
  103,255,255,255
  128,255,255,255
  q
  q

--

David Ovens             e-mail: address@hidden
(206) 685-8108          plan: Real-time MM5 forecasting for Pacific Northwest
Research Meteorologist
Dept of Atmospheric Sciences, Box 351640
University of Washington
Seattle, WA  98195

On Mon, 4 Mar 2002, Christian Page wrote:

>
> Hi everyone,
>
> I try to match an enhancement table I have for Water Vapor Imagery. I created 
> it
> successfully in McIDAS:
>
>  Brightness  Blue      Green      Red
>   min max   min max   min max   min max
>   --- ---   --- ---   --- ---   --- ---
>     0 136     0   0     0   0     0   0
>   137 205   165 255     0 255     0 255
>   206 255   255 255   255 255   255 255
>
> I tried to create a LUTFIL for GEMPAK that exhibits the same enhancement 
> without
> any success.
>
> Is there a way to match a McIDAS enhancement table to a GEMPAK LUTFIL?
>
> Best regards,
>
> Christian Page
> address@hidden    http://meteocentre.com/
>
> Agent de recherche et de planification +1 514 987 3000 ext. 2376
> Departement des Sciences de la Terre et de l'Atmosphere UQAM


#!/usr/local/bin/perl

unless (open (OUT,">mytopo.tbl")) {
    print "cannot create mytopo.tbl\n";
    exit 1;
}
print OUT "! mytopo.tbl
!
! Color table generated by ~ovens/gempak/make_sat_enhancement_table.pl
!
!Color name    Abrev   Red  Green   Blue  X color name
";
print "enter total number of colors 256,128,64,32, etc: ";
chomp($num = <STDIN>);
$input = "$num\n";

$total = 0;
until ($srgb eq "q") {
    print "enter START color number,r,g,b or q to quit (e.g. 1,255,255,255: ";
    chomp($srgb = <STDIN>);
    $input .= "$srgb\n";
    print "enter END color number,r,g,b (e.g. 256,0,0,255: ";
    chomp($ergb = <STDIN>);
    $input .= "$ergb\n";
    ($start,$sr,$sg,$sb) = split(',',$srgb);
    ($end,$er,$eg,$eb) = split(',',$ergb);
    if ($start == $end) {
        $total++;
        if ($total > $num) {
            print "written $num colors to mytopo.tbl\n";
            $srgb = "q";
            last;
        }
        print sprintf "                       %3d    %3d    %3d    
%3d\n",$sr,$sg,$sb,$total;
        print OUT sprintf "                       %3d    %3d    %3d    
%3d\n",$sr,$sg,$sb,$total;
    } else {
        for ($i = $start; $i <= $end; $i++) {
            $red_int = ($er - $sr)/($end - $start);
            $green_int = ($eg - $sg)/($end - $start);
            $blue_int = ($eb - $sb)/($end - $start);
            $total++;
            if ($total > $num) {
                print "written $num colors to mytopo.tbl\n";
                $srgb = "q";
                last;
            }
            print sprintf "                       %3d    %3d    %3d    
%3d\n",int(($i-$start)*$red_int+$sr+0.5),int(($i-$start)*$green_int+$sg+0.5),int(($i-$start)*$blue_int+$sb+0.5),$total;
            print OUT sprintf "                       %3d    %3d    %3d    
%3d\n",int(($i-$start)*$red_int+$sr+0.5),int(($i-$start)*$green_int+$sg+0.5),int(($i-$start)*$blue_int+$sb+0.5),$total;
        }
    }
}
close OUT;
open(OUT,">mytopo.in");
print OUT $input;
close OUT;


>From address@hidden Mon Mar  4 13:26:46 2002
>To: David Ovens <address@hidden>
>cc: <address@hidden>
>Subject: Re: GEMPAK LUTFIL vs McIDAS ET file

Hi,

Thank you very much!! It works very well and it is very fast...

Best regards!

Christian Page
address@hidden    http://meteocentre.com/

Agent de recherche et de planification +1 514 987 3000 ext. 2376
Departement des Sciences de la Terre et de l'Atmosphere UQAM