graphics scrbook footer

Remy,

I'd recommend you post a minimal working latex document with your question, e.g.

\documentclass{scrbook}
\usepackage{scrpage2}
\usepackage{graphicx}
\pagestyle{scrheadings}
\cfoot{\includegraphics[width=5cm]{footer.eps}}
\begin{document}
Hello world.
\end{document}

Now, it is VERY hard to help you with the little information you give.
(a) di you define a pagestyle (such as \pagestyle{scrheadings} )?
(b) what's your output? dvi / ps / pdf?
(c) how do you generate your output? tex->ps->pdf / latex2pdf etc...
(d) your eps file does certainly NOT have 595x34 pixels as it is a vector format that is scalable at will. Try to give your \includegraphics a scale option with it, as in the example above.
(e) if your image is actually a raster graphic (pixels!) try to test your code with a true vector image to check if your (footer.eps)-image isn't corrupted.

Cheers
Ralfito