\documentclass{beamer}
\mode<presentation>{\usetheme{Madrid}\setbeamercovered{transparent}}
\usepackage[german]{babel}
\usepackage[latin1]{inputenc}
\usepackage[T1]{fontenc}
\usepackage{ifpdf}
\usepackage{graphicx}
\usepackage{color}
\ifpdf
\hypersetup{pdfpagemode=FullScreen}
\fi
\title[Beamer and png2pdf]{Using png2pdf with the beamer class}
\author[Krause]{D.~Krause}
\subject{png2pdf}
\begin{document}
\beamertemplateshadingbackground{yellow!50}{magenta!50}
\begin{frame}
\frametitle{Image over transient background}
\includegraphics[width=5cm]{x4.pdf}
\end{frame}
\end{document}
