How do I show an image across a beamer slide?

Question

I would like to have a beamer frame such that it shows an image, but stretches it across the whole slide so that it fits exactly, leaving no margin or no title. The image is indeed the right proportions for a beamer slide.

MWE:

\documentclass{beamer}

\begin{document}

\begin{frame}
\includegraphics{fullslide.png}
\end{frame}

\end{document}

I suppose I either need to (or both):

1. change the style of the beamer frame to have no margin, no title, etc.
2. stretch (hopefully automatically) the image on the slide.

Answer 1

Just overlay the image in the ForeGround of a (blank) slide:

\documentclass{beamer}

\usepackage{eso-pic}

\begin{document}

\begin{frame}
  Some regular text frame
\end{frame}

\begin{frame}
  \mbox{}% Any (blank) content
  \AddToShipoutPictureFG*{%
    \AtPageLowerLeft{%
      \includegraphics[width = \paperwidth, height = \paperheight]{example-image}%
    }%
  }
\end{frame}

\begin{frame}
  Some more frame content
\end{frame}

\end{document}