> I'm using convert (from imagemagick) to crop and convert pbm > images into encapsulated postscript. When I prefix the output > filename with eps2: I get a very compact EPS file where the image > data is contained as binary like this: [snip]
Okay, I just completed a few tests and my conclusion is that
the fact that it's binary is not by itself the best criterion
regarding compactness. Depending on the type of your images,
flate compression + ASCII base-85 can be almost as good as
or even much better:
convert lena.ppm lena.eps2
gs -q -dNODISPLAY -dBATCH -dNOPAUSE ppmtops.ps <lena.ppm >lena.ps
49167 lena.ppm
53624 lena.eps2
59425 lena.ps
"lena" is a rather "noisy" image and compression doesn't seem
to be very effective. What you're seeing here is probably
mostly the 7-bit/8-bit difference in the encoding.
On the other hand, "teapot" is a very smooth image, and
compression really shines here:
convert teapot.ppm teapot.eps2
gs -q -dNODISPLAY -dBATCH -dNOPAUSE ppmtops.ps <teapot.ppm >teapot.ps
196623 teapot.ppm
201258 teapot.eps2
53708 teapot.ps
And if you have JPEG files, it's best to keep them that way
and simply wrap them with a simple DCT decoder in Postscript,
as Thomas Merz's jpeg2ps does.
ppmtops.ps
Description: PostScript document
