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You can usually reduce or eliminate Postscript bloat if you understand your Postscript. Computers cannot understand Postscript well enough to do it automatically, because Postscript, like TeX, is a full-fledged programming language. However, two Unix utilities can often fix the problem:

 * convert is a bitmap-based image conversion program which is part of the 
    ImageMagick graphics package. It interconverts nearly 100 different image 
    formats, including several kinds of Postscript. 
 * eps2eps, which is part of the ghostscript package, converts fancy Postscript    
    to simple Postscript. The output is frequently much shorter than the input, 
    even though it is functionally identical. However, it does not help much 
    with bitmaps.

    * The file is a huge bitmap. This is usually because the resolution is  
 substantially higher than necessary, because it is a black-and-white diagram 
 saved as a full-color photograph, or because it is encoded inefficiently (using 
 as many as 12 bytes per pixel). If you include the figure in your TeX document 
 without rescaling it, then you should try:

      convert -density 300x300 fig.old.eps eps2:fig.new.eps

      With these options, convert produces 300dpi output in Postscript Level 2 
 format. Occassionally 600dpi is necessary for fine detail or 150dpi is 
 necessary to further save space; resolutions other than these three are rarely 
 the best choice. If you rescale the figure when you include it in your TeX 
 document, you should change the parameters in convert so that the scaled 
 resolution matches one of these values, or at least so that it's in a 
 reasonable range.

    * The file has a huge header with a lot of macros or fonts. This is typical 
 for commercial illustration programs such as Adobe Illustrator. Try the  
 following conversion:

    eps2eps fig.old.eps fig.new.eps

      You should check the size of the output (preferably after compressing both 
 the old and new figures) to make sure that it really is smaller.

    * The file is an extremely complicated figure with tens of thousands of 
 vertices, each given with many digits of precision. Sometimes you can fix the 
 problem by changing the settings of the program that generated the figure. For 
 example, a 3D plotting program might have an option to omit points that are 
 hidden from view. Alternatively, you can convert it to a bitmap.

 Note that if you create the Postscript judiciously a priori, you might not need 
 to convert it all. For example, the free illustration program xfig produces 
 very lean Postscript output. As another example, it is easy to produce huge 
 files with commercial photography software such as Adobe Photoshop, but more 
 careful use may produce better results. You can also first produce some other 
 format (such as TIFF or JPEG) and then use convert to make the Postscript.