You can do this in number of ways. I will show three more methods.
With tikz
:
\documentclass{article}
\usepackage{tikz}
\usepackage[top=2cm, bottom=2cm, outer=0cm, inner=0cm]{geometry}
\begin{document}
Some content
\tikz[remember picture,overlay] \node[opacity=0.3,inner sep=0pt] at (current page.center){\includegraphics[width=\paperwidth,height=\paperheight]{example-image}};
\clearpage
text
\end{document}
With eso-pic
:
\documentclass{article}
\usepackage{eso-pic,graphicx}
\usepackage[top=2cm, bottom=2cm, outer=0cm, inner=0cm]{geometry}
\begin{document}
Some content
\AddToShipoutPictureBG*{\includegraphics[width=\paperwidth,height=\paperheight]{example-image}};
\clearpage
text
\end{document}
\AddToShipoutPictureBG
(instead of \AddToShipoutPictureBG*
) puts the background in all pages.
With background
package:
\documentclass{article}
\usepackage[top=2cm, bottom=2cm, outer=0cm, inner=0cm]{geometry}
\usepackage[pages=some]{background}
\backgroundsetup{
scale=1,
color=black,
opacity=0.4,
angle=0,
contents={%
\includegraphics[width=\paperwidth,height=\paperheight]{example-image}
}%
}
\begin{document}
\BgThispage
Some content
\clearpage
text
\end{document}