另一种方法可能是用半透明形状临时覆盖图像:
\documentclass{beamer}
\usepackage{tikz}
\setbeamercovered{dynamic}
\begin{document}
\begin{frame}
\begin{figure}
\includegraphics[width=2cm,page=1]{example-image-duck}
Test A
\pause
\begin{tikzpicture}
\node[anchor=south west,inner sep=0] (B) at (4,0) {\includegraphics[width=2cm,page=2]{example-image-duck}};
\only<1>{%
\fill [draw=none, fill=white, fill opacity=0.7] (B.north west) -- (B.north east) -- (B.south east) -- (B.south west) -- (B.north west) -- cycle;
}
\end{tikzpicture}
Test B
\pause
\begin{tikzpicture}
\node[anchor=south west,inner sep=0] (B) at (4,0) {\includegraphics[width=2cm,page=3]{example-image-duck}};
\only<1-2>{%
\fill [draw=none, fill=white, fill opacity=0.7] (B.north west) -- (B.north east) -- (B.south east) -- (B.south west) -- (B.north west) -- cycle;
}
\end{tikzpicture}
Test C
\end{figure}
\end{frame}
\end{document}
