[tex-eplain] pdftex + png images

[Karl Berry]

    how can I include an image in png format when using pdftex?

pdftex understands png (and jpg and pdf) natively.  So you can use the
primitives for straightforward inclusions:
\immediate\pdfximage width 1in {yourimage.png}\pdfrefximage\pdflastximage


If you want fancier options, a la the graphics/graphicx package, you can
load those packages using Eplain.
http://tug.org/eplain/doc/eplain/Loading-LaTeX-packages.html

Best,
Karl