To import a slide from another beamer presentation as a "picture", you can use pdfpages. You'll have to \setbeamercolor{background canvas}{bg=} as explained in this answer because only a white frame will be shown otherwise:
\documentclass{beamer}
\usepackage{pdfpages}
\begin{document}
\begin{frame}
Content
\end{frame}
{
\setbeamercolor{background canvas}{bg=}
\includepdf[pages=3]{filea.pdf}
}
\end{document}
However, if you use head- or footlines or even a different theme in your existing presentation, this will probably not fit snugly. In this case, a better solution would be to actually import the source code of the existing presentation, which can be done using the docmute package in combination with the \againframe command:
Suppose this is your existing presentation filea.tex: You need to give the slides you want to import a name using the label option of the frame environment, like this:
\documentclass{beamer}
\begin{document}
\begin{frame}[label=myframe]
Frame to be included
\end{frame}
\end{document}
Then you can use this code in your new presentation:
\documentclass{beamer}
\usepackage{docmute}
\makeatletter
\newcommand*{\loadpresentation}[1]{{\beamer@inlecturefalse\input{#1}}}
\makeatother
\begin{document}
\loadpresentation{filea.tex}
\begin{frame}
The new presentation
\end{frame}
\againframe{myframe}
\end{document}
Issuing \loadpresentation{filea.tex} imports the frames from your existing presentation without displaying them. You can insert them wherever needed using \againframe with the label you chose in filea.tex. The command \loadpresentation should be used someplace after \begin{document} (but before you actually include a frame from this presentation, of course).
This works roughly the same as if you'd actually copy the source code of the frame from the existing presentation, so things like overlays etc. are taken over.
You can first define a "6 on 1" pgf page layout, then activate it in, say, the handout mode. I use the code below -- I've probably modified it from somewhere but I can't remember. Perhaps you can fine tune it further for your own needs:
\documentclass[handout]{beamer}
\usetheme{Dresden}
\usepackage{pgfpages}
\pgfpagesdeclarelayout{6 on 1}
{
\edef\pgfpageoptionheight{\the\paperwidth} % landscaped by default
\edef\pgfpageoptionwidth{\the\paperheight}
\def\pgfpageoptionborder{0pt}
\def\pgfpageoptionfirstshipout{1}
}
{
\pgfpagesphysicalpageoptions
{%
logical pages=6,%
physical height=\pgfpageoptionheight,%
physical width=\pgfpageoptionwidth,%
current logical shipout=\pgfpageoptionfirstshipout%
}
\ifdim\paperheight>\paperwidth\relax
% put side-by-side
\pgfpageslogicalpageoptions{1}
{%
border shrink=\pgfpageoptionborder,%
resized width=.5\pgfphysicalwidth,%
resized height=\pgfphysicalheight,%
center=\pgfpoint{.1667\pgfphysicalwidth}{.25\pgfphysicalheight}%
}%
\pgfpageslogicalpageoptions{3}
{%
border shrink=\pgfpageoptionborder,%
resized width=.5\pgfphysicalwidth,%
resized height=\pgfphysicalheight,%
center=\pgfpoint{.5\pgfphysicalwidth}{.25\pgfphysicalheight}%
}%
\pgfpageslogicalpageoptions{5}
{%
border shrink=\pgfpageoptionborder,%
resized width=.5\pgfphysicalwidth,%
resized height=\pgfphysicalheight,%
center=\pgfpoint{.8333\pgfphysicalwidth}{.25\pgfphysicalheight}%
}%
\pgfpageslogicalpageoptions{2}
{%
border shrink=\pgfpageoptionborder,%
resized width=.5\pgfphysicalwidth,%
resized height=\pgfphysicalheight,%
center=\pgfpoint{.1667\pgfphysicalwidth}{.75\pgfphysicalheight}%
}%
\pgfpageslogicalpageoptions{4}
{%
border shrink=\pgfpageoptionborder,%
resized width=.5\pgfphysicalwidth,%
resized height=\pgfphysicalheight,%
center=\pgfpoint{.5\pgfphysicalwidth}{.75\pgfphysicalheight}%
}%
\pgfpageslogicalpageoptions{6}
{%
border shrink=\pgfpageoptionborder,%
resized width=.5\pgfphysicalwidth,%
resized height=\pgfphysicalheight,%
center=\pgfpoint{.8333\pgfphysicalwidth}{.75\pgfphysicalheight}%
}%
\else
% stack on top of one another
\pgfpageslogicalpageoptions{1}
{%
border shrink=\pgfpageoptionborder,%
resized width=0.5\pgfphysicalwidth,%
resized height=\pgfphysicalheight,%
center=\pgfpoint{.25\pgfphysicalwidth}{.8333\pgfphysicalheight}%
}%
\pgfpageslogicalpageoptions{3}
{%
border shrink=\pgfpageoptionborder,%
resized width=0.5\pgfphysicalwidth,%
resized height=\pgfphysicalheight,%
center=\pgfpoint{.25\pgfphysicalwidth}{.5\pgfphysicalheight}%
}%
\pgfpageslogicalpageoptions{5}
{%
border shrink=\pgfpageoptionborder,%
resized width=0.5\pgfphysicalwidth,%
resized height=\pgfphysicalheight,%
center=\pgfpoint{.25\pgfphysicalwidth}{.1667\pgfphysicalheight}%
}%
\pgfpageslogicalpageoptions{2}
{%
border shrink=\pgfpageoptionborder,%
resized width=0.5\pgfphysicalwidth,%
resized height=\pgfphysicalheight,%
center=\pgfpoint{.75\pgfphysicalwidth}{.8333\pgfphysicalheight}%
}%
\pgfpageslogicalpageoptions{4}
{%
border shrink=\pgfpageoptionborder,%
resized width=0.5\pgfphysicalwidth,%
resized height=\pgfphysicalheight,%
center=\pgfpoint{.75\pgfphysicalwidth}{.5\pgfphysicalheight}%
}%
\pgfpageslogicalpageoptions{6}
{%
border shrink=\pgfpageoptionborder,%
resized width=0.5\pgfphysicalwidth,%
resized height=\pgfphysicalheight,%
center=\pgfpoint{.75\pgfphysicalwidth}{.1667\pgfphysicalheight}%
}%
\fi
}
\mode<handout>{
\pgfpagesuselayout{6 on 1}[a4paper, border shrink=8mm]
\pgfpageslogicalpageoptions{1}{border code=\pgfusepath{stroke}}
\pgfpageslogicalpageoptions{2}{border code=\pgfusepath{stroke}}
\pgfpageslogicalpageoptions{3}{border code=\pgfusepath{stroke}}
\pgfpageslogicalpageoptions{4}{border code=\pgfusepath{stroke}}
\pgfpageslogicalpageoptions{5}{border code=\pgfusepath{stroke}}
\pgfpageslogicalpageoptions{6}{border code=\pgfusepath{stroke}}
}
\begin{document}
\begin{frame}{First}
lala
\end{frame}
\begin{frame}{Second}
lala
\end{frame}
\begin{frame}{Third}
lala
\end{frame}
\begin{frame}{Fourth}
lala
\end{frame}
\begin{frame}{Fifth}
lala
\end{frame}
\begin{frame}{Sixth}
lala
\end{frame}
\end{document}
Best Answer
Your PDF image contains text in Helvetica, but the font has not been embedded:
Even though Helvetica should be a PDF standard font, I have often experienced problems with PDF images that do not embedd all uses glyphs. Hence, you should export it in a way that font (subsets) get embedded.
If the respective fonts are installed on your system in a way that ghostscript can find them (which should be the case for all standard PS fonts), you may also use ghostscript to convert your PDF to PS and then to PDF with the
prepresssetting, resulting in a version that embeds the used glyphs: