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(dvips.info)Bounding box

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The bounding box comment
------------------------

  The most important feature of a good PostScript file from the
standpoint of including it in another document is an accurate bounding
box comment.  Every well-formed PostScript file has a comment
describing where on the page the graphic is located, and how big that
graphic is.

  This information is given as the lower left and upper right corners of
the box just enclosing the graphic, and is thus referred to as the
"bounding box".  These coordinates are given in the default PostScript
units (there are precisely 72 PostScript units to the inch, like TeX
big points) with respect to the lower left corner of the sheet of paper.

  To see if a PostScript file has a bounding box comment, just look at
the first few lines of the file.  PostScript files are standard ASCII,
so you can use any text editor to do this.  If within the first few
dozen lines there is a line like

     %%BoundingBox: 25 50 400 300

(with any reasonable numbers), chances are very good that the file is
Encapsulated PostScript and will work easily with Dvips.  If the file
contains instead a line like

     %%BoundingBox: (atend)

the file is still probably Encapsulated PostScript, but the bounding box
is given at the end of the file.  Dvips needs it at the beginning.  You
can move it with that same text editor, or a simple script.  (The
bounding box is given in this way when the program that generated the
PostScript couldn't know the size in advance, or was too lazy to compute
it.)

  If the document lacks a `%%BoundingBox:' altogether, you can
determine one in a couple of ways.  One is to use the `bbfig' program
distributed with Dvips in the `contrib' directory. This can usually
find the correct bounding box automatically; it works best with
Ghostscript.

  If the comment looks like this:
     %%BoundingBox: 0 0 612 792

the graphic claims to take up an entire sheet of paper.  This is
usually a symptom of a bug in the program that generated it.

  The other is to do it yourself: print the file.  Now, take a ruler,
and make the following measurements (in PostScript units, so measure in
inches and multiply by 72): From the left edge of the paper to the
leftmost mark on the paper is LLX, the first number.  From the bottom
edge of the paper to the bottommost mark on the paper is LLY, the
second number.  From the left edge of the paper to the rightmost mark
on the paper is URX, the third number.  The fourth and final number,
URY, is the distance from the bottom of the page to the uppermost mark
on the paper.

  Once you have the numbers, add a comment of the following form as the
second line of the document.  (The first line should already be a line
starting with the two characters `%!'; if it is not, the file probably
isn't PostScript.)

     %%BoundingBox: LLX LLY URX URY

Or, if you don't want to modify the file, you can simply write these
numbers down in a convenient place and give them in your TeX document
when you import the graphic, as described in the next section.

  If the document does not have such a bounding box, or if the bounding
box is given at the end of the document, or the bounding box is wrong,
please complain to the authors of the software package that generated
the file.