beamerの暗い背景に画像を挿入する

http://tex.stackexchange.com/questions/18685/techniques-for-embedding-images-with-transparent-backgrounds-in-latex
 
 
You need the standard packge graphicx to include the mage.Loaded xcolor would also be a good idea.Here some examples which use a tranparent test PNG I got from http://entropymine.com/jason/testbed/pngtrans/rgba16.png.
 
書き記す
\documentclass{articale}
\usepackage{xカラー}
\usepackage{graphcx}
\begin{document}
\frame ebox{\includegraphics{rgba 16 png}
\colorbox{red}{includegraphics{rgba 16 png}
\colorbox{white}{includegraphics{rgba 16 png}
\colorbox{yellow}{includegraphics{rgba 16 png}
\end{document}
  The first image shown is the original transparent PNG.As you can see the other work fine with some backgroundカラー.

For advanced effects like patterns and shardings I would recommand you PGF/TikZ(i.e.the tikz package)
 
書き記す
\documentclass{articale}
\usepackage{tikz}
\usetizlibrary{patterns}
\begin{document}
\begin{tikzpicture}
ode[pattern=north eartt lines,inner sep=10 pt]｛includegraphics｛rgba 16 png｝
\end{tikzpicture}
\begin{tikzpicture}
ode[shard,leftカラー=yellow,rightカラー=blue,inner sep=10 pt]{includegraphics{rgba 16.6 png}
\end{tikzpicture}
\end{document}