# How to write a picture's source description in a beamer document?

In writing a presentation using beamer, and I would like to add "source information" to my graphs (under the picture). I've implemented the great solution I found here: How to write a source description under the loaded picture and it works fine for me on a article document class.

But I cannot make it work on a beamer document. It inserts the figure caption above and below the figure.

My code is:

\begin{frame}
\begin{figure}[H]
\centering
\caption{Vriance decomposition}
\caption*{Source of the image.}
\end{figure}
\end{frame}


The output is:

One way is use of copyrightbox:

\documentclass{beamer}
\setbeamertemplate{caption}[numbered] % if you like to have numbered figures
%
\makeatletter
{\tiny\color{gray}}
\makeatother

\begin{document}
\begin{frame}
\begin{figure}
\caption{Variance decomposition}
{Source of the image.}
\end{figure}
\end{frame}
\end{document}


Note: figure environment in beamer doesn't float, so it is not need any positioning option. It also is always centered, so \centering is not needed.

Without the \caption* command you can use something like the following:

\documentclass{beamer}

\begin{document}

\begin{frame}