dvipng: Bitmapped graphics
5.2 Bitmapped graphics
======================
dvipng can include PNG, JPEG and GIF graphics. When including such
images via '\includegraphics' you need to specify the bounding box since
TeX itself cannot read them from the files in question. The bounding
box size should be given as '0 0 w h' in pixels, e.g., if the file
'imagename.png' is 300x400 pixels, the inclusion would read
\includegraphics[bb=0 0 300 400]{imagename.png}
The default size is the image size in bp ("big points" in TeX
nomenclature or PostScript points as other people have it, 72 per inch).
That is, default resolution will be 72 dpi for included bitmaps, which
is the default size in the few other bitmap-capable drivers that are
known to me (dvipdfm and PDFLaTeX).
If you want 100 dpi you need to specify the width accordingly. You
just divide your image width by 100: a 135 pixel wide image at 100 dpi
will take up 1.35 inches. If you want 200 dpi you divide by 200, and so
on. Simple, eh? The example above at 200 dpi would be 1.5 inches wide:
\includegraphics[bb=0 0 300 400,witdh=1.5in]{imagename.png}
Info Catalog
dvipng: Encapsulated PostScript
dvipng: Graphics
dvipng: Raw PostScript