答案1
您可以修改侧边栏模板以满足您的需要:
\documentclass{beamer}
\useoutertheme[height=0pt,left,width=1cm]{sidebar}
\setbeamercolor{sidebar}{use=structure,bg=structure.fg!20!white,fg=white}
\makeatletter
\setbeamertemplate{sidebar left}{%
\begin{minipage}[t][.98\paperheight][t]{1cm}%
\vskip1.5em%
\centering
\includegraphics[width=.9\textwidth]{example-image}
\vfill
\usebeamercolor[fg]{sidebar}
\insertframenumber
\vskip1.5em%
\end{minipage}
}%
\makeatother
\begin{document}
\begin{frame}
abc
\end{frame}
\end{document}