Beginning with GrADS version 2.1, the printim command has been deprecated and is  an alias for gxprint.  
The printim command will produce a PNG, GIF, or JPG formatted
image file based on the current contents of the metabuffer, which is
usually the stuff displayed on the screen, minus any widgets.  The
syntax is:
printim filename options 
where:
filename:  The name of the output file. If this 
  file exists, it will be replaced. 
              If the filename ends with ".png" or ".PNG" then GrADS will automatically create the image in PNG format           If the filename ends with ".gif" or ".GIF" then GrADS will automatically create the image in GIF format           If the filename ends with ".jpg" or ".JPG" then GrADS will automatically create the image in JPEG format options:   png  
    - produce PNG output (default)
               gif 
     - produce GIF output 
               jpg 
     - produce JPEG output 
               black 
     - use black background (default is current display setting)
               white 
     - use white background (default is current display setting)
               xNNN  
    - horizontal size in NNN pixels
               yNNN  
    - vertical size in NNN pixels
               -t NN  
    - color number NN is transparent
               -b bgImage  
    - Image file bgImage s included in the background of the output. 
               -f fgImage  
    - Image file fgImage is included in the foreground of the output.
  
 One or more options may be given in any order. bgImage 
  and fgImage must be PNG format. 
printim works with GrADS version 1.8 (or higher). Beginning with version 2.1, printim is an alias for gxprint. 
printim can be used while in batch mode. 
bgImage and fgImage should not contain any upper case letters. 
The following command produces a 1000x800 PNG image into file out.png:
printim out.png x1000 y800This command produces a 800x600 GIF image, with a white background, into file gifimage.out:
printim gifimage.out gif x800 y600 white
This command produces a GIF image with transparent color 0 and a background image mybkg.png. This means that in image.gif, the background image mybkg.png will be seen wherever the color 0 (background) appeared in the current display.
printim image.gif -b mybkg.png -t 0