Dvipdfm translates direct from DVI to PDF (all other available routes produce PostScript output using dvips and then convert that to PDF with ghostscript or Acrobat Distiller).
Dvipdfm is a particularly flexible application. It will
permit the inclusion of bitmap and PDF graphics, as does
PDFTeX, but is also capable of employing
ghostscript "on the fly" so as to be able to permit the
inclusion of encapsulated PostScript (.eps) files by translating
them to PDF. In this way, dvipdfm combines the good
qualities of dvips and of PDFTeX as a means of
processing illustrated documents.
Unfortunately, "ordinary" LaTeX can't deduce the bounding box of a binary bitmap file (such as JPEG or PNG), so you have to specify the bounding box. This may be done explicitly, in the document:
\usepackage[dvipdfm]{graphicx}
...
\includegraphics[bb=0 0 540 405]{photo.jpg}
It's usually not obvious what values to give the "bb" key,
but the program ebb will generate a file
containing the information; the above numbers came from an
ebb output file photo.bb:
However, if such a file is available, you may abbreviate the inclusion code, above, to read:%%Title: /home/gsm10/photo.jpg %%Creator: ebb Version 0.5.2 %%BoundingBox: 0 0 540 405 %%CreationDate: Mon Mar 8 15:17:47 2004
\usepackage[dvipdfm]{graphicx}
...
\includegraphics{photo}
which makes the operation feel as simple as does including
.eps images in a LaTeX file for processing with
dvips; the graphicx package knows to look for a
.bb file if no bounding box is provided in the
\includegraphics command.
The one place where usage isn't quite so simple is the need to quote
dvipdfm explicitly, as an option when loading the
graphicx package: if you are using dvips, you
don't ordinarily need to specify the fact, since the default graphics
configuration file (of most distributions) "guesses" the
dvips option if you're using TeX.
This question on the Web: http://www.tex.ac.uk/cgi-bin/texfaq2html?label=dvipdfmgraphics