[Tex/LaTex] Black bar at the bottom of slides

Question

Due to restrictions of the prjection space, I cannot use the full frame size, thus I want to add a black bar at the bottom of every slide (underneath the footer). Therefore I effectively reduce the hight of each slide.

Is there an easy way to achieve this while still using a standard beamer theme?

Answer 1

You can do it by modifying the footer. Of course this depends on the theme you use, but in the example below in line 24 you can adjust the 2.25ex to how thick you need the black bar.

\documentclass{beamer} 
\usetheme{Madrid}

\setbeamercolor{back}{fg=black,bg=black}

\makeatletter
\setbeamertemplate{footline}
{
  \leavevmode%
  \hbox{%
      \begin{beamercolorbox}[wd=.333333\paperwidth,ht=2.25ex,dp=1ex,center]{author in head/foot}%
        \usebeamerfont{author in head/foot}\insertshortauthor
      \end{beamercolorbox}%
      \begin{beamercolorbox}[wd=.333333\paperwidth,ht=2.25ex,dp=1ex,center]{title in head/foot}%
        \usebeamerfont{title in head/foot}\insertshorttitle
      \end{beamercolorbox}%
      \begin{beamercolorbox}[wd=.333333\paperwidth,ht=2.25ex,dp=1ex,right]{date in head/foot}%
        \usebeamerfont{date in head/foot}\insertshortdate{}\hspace*{2em}
        \insertframenumber{} / \inserttotalframenumber\hspace*{2ex} 
      \end{beamercolorbox}%
  }%

  \hbox{%
    \begin{beamercolorbox}[wd=\paperwidth,ht=2.25ex,dp=1ex,center]{back}%
    \end{beamercolorbox}%
    }%
  \vskip0pt%
}
\makeatother
\begin{document}


\author{A.U. Thor}
\institute{The Institute}

\begin{frame}
Test
\end{frame}

\end{document}