Making animated GIF movies from NCAR graphics

R. Fovell, August, 1998

This page details the easiest way (yet) I've found for making animated GIF movies from NCAR graphics metafile frames. Such files can be embedded into web pages, and makes for the nice display of model simulation data. If you've any better ideas, please let me know!

Required:

• Unix platform (we have these on our Sun workstations):
  • NCAR graphics package (including ctrans program)
  • NETPBM package
• Apple Macintosh platform:
  • GraphicConverter (latest version), available from VersionTracker and other sources.

On the Unix workstation:

• Start with NCAR graphics metafile "gmeta" containing many frames.
• Convert "gmeta" to one large postscript (PS) file containing all the frames.

  % ctrans -d ps.color -f font12 gmeta > massive.ps

  this creates the file "massive.ps"

• Convert the massive PS file into PPM format. This action distributes the images into separate files.

  % /opt/local/bin/netpbm/pstopnm massive.ps

  this creates the files "massive001.ppm", "massive002.ppm", etc.

• Run the following script to convert the PPM files to GIF format in batch. (Save this script in an executable file.)

  #!/bin/csh

  foreach i (*.ppm)

  echo $i

  \rm crap.ppm

  cp $i crap.ppm

  /opt/local/bin/netpbm/ppmtogif crap.ppm > `echo $i | sed s',ppm,gif,'`

  end

  this creates the files "massive001.gif", "massive002.gif", etc.

On the Mac:

• FTP the GIF files to the Mac (with Fetch, for example). Use binary mode (or simply choose "automatic" with Fetch).
• Run GraphicConverter.
• Choose File > Convert more...
  
• In the left window pane, select all of the GIF files to be included in the animation.
• In the right window pane, select the destination for the movie file (should be a different folder/location).
• On the right side, choose "Dest. format" to be GIF and click the "Options" button. The "GIF" options window appears.
  
• In the GIF options window, check "Create movie" and "Loop". If you choose "0" for the Loop, it will loop endlessly.
• Then, in the "Convert more" window, click "Convert". The movie will be located in the chosen destination location, and will be named after the first filename that was used to create the animated GIF. That's it!

Note: On our Solaris 8 machines, the NETPBM package is in a different place. Change all references to /opt/local/bin/netpbm to /opt/local/pbm/bin.

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Page created August, 1998, by Robert Fovell