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[GEMPAK #TMZ-590514]: Custom Gempak color tables

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  • Subject: [GEMPAK #TMZ-590514]: Custom Gempak color tables
  • Date: Fri, 15 Feb 2013 12:39:05 -0700
HI  Shawn,

coltbl defines 32 colors for graphics, contours, lines and text and that file 
can not be added to without possibly breaking some GEMPAK graphic capabilities. 
 GEMPAK can use up to 95 colors for satellite images and high-resolution radar. 
for a satellite image with a contour overlay, the gif and xw devices can handle 
95+32=127.

 As for using more than one color table at a time, no, that's not possible 
either.

I have had limited success in the past using imagemagick convert utility to 
change the hex value of colors for GIF images, and used it to overlay multiple 
images with transparency and color modification to spoof a more modern look, 
but that is all post-processing of the 32 colors the gif device can maintain.  
I chased a rabbit down a hole a few years ago attempting to increase the number 
of colors handled and I ended up in a large mess of broken code so I cut my 
losses and moved on.  

-Michael 


> Full Name: Shawn Milrad
> Email Address: address@hidden
> Organization: Embry-Riddle Aeronautical University
> Package Version: 6.2.0
> Operating System:
> Hardware:
> Description of problem:
> 
> Hi,
> 
> I've been trying to create custom color tables to use in Gempak by editing
> coltbl.tbl etc.  I've been mostly successful, but have noticed that the
> limit seems to be 32 colors no matter what you do.  Is there any way
> to create a color table with more than 32 colors?  Or, alternatively,
> is there any way to use more than one color table at a time when running
> e.g. gdcntr?
> 
> Thanks in advance for your help!
> 
> -Shawn Milrad
> 
> 


Ticket Details
===================
Ticket ID: TMZ-590514
Department: Support GEMPAK
Priority: Normal
Status: Open