\documentclass{article}
\pagestyle{empty}
\usepackage{arrayjob}
\usepackage{multido}
\usepackage{pstricks}
\usepackage{pst-char}
% Manuel Luque
% Denis Girou
\input{random} % Donald Arseneau
\DeclareFixedFont{\Rm}{T1}{ptm}{m}{n}{4cm}

\newarray\colorCyan
\newarray\colorMagenta
\newarray\colorYellow
\expandarrayelementtrue
\psset{dimen=middle}
\makeatletter
\def\GraphicBackground(#1,#2){%
% #1 = horizontal size, #2 = vertical size
\multido{\iLineMOne=\z@+\@ne,\iLine=\@ne+\@ne}{#1}{%
  \multido{\iColumnMOne=\z@+\@ne,\iColumn=\@ne+\@ne}{#2}{%
    \setrandim{\pst@dima}{\z@}{0.4pt}%
    \global\colorCyan(\iLine,\iColumn)={\pointless\pst@dima}
    \setrandim{\pst@dimb}{\z@}{0.4pt}%
    \global\colorMagenta(\iLine,\iColumn)={\pointless\pst@dimb}
    \setrandim{\pst@dimc}{\z@}{0.4pt}%
    \global\colorYellow(\iLine,\iColumn)={\pointless\pst@dimc}
    \definecolor{MyColor}{cmyk}{\pointless\pst@dima,\pointless\pst@dimb,\pointless\pst@dimc,0}%
    \psframe[fillstyle=solid,fillcolor=MyColor,linestyle=none]%
      (\iLineMOne,\iColumnMOne)(\iLine,\iColumn)}}}

\def\TextTransparent(#1,#2,#3)(#4,#5)#6{%
% #1, #2, #3 = cyan, magenta and yellow components of the color filter,
% #4, #5 = horizontal and vertical indices,
% #6 = text
  \checkcolorCyan(#4,#5)%
  \pst@dima\cachedata pt
  \advance\pst@dima by #1pt
  \ifdim\pst@dima>\@ne pt\pst@dima=\@ne pt\fi
  \checkcolorMagenta(#4,#5)%
  \pst@dimb=\cachedata pt
  \advance\pst@dimb by #2pt
  \ifdim\pst@dimb>\@ne pt\pst@dimb=\@ne pt\fi
  \checkcolorYellow(#4,#5)%
  \pst@dimc=\cachedata pt
  \advance\pst@dimc by #3pt
  \ifdim\pst@dimc>\@ne pt\pst@dimc=\@ne pt\fi
  \definecolor{MyColor}{cmyk}{\pointless\pst@dima,\pointless\pst@dimb,\pointless\pst@dimc,0}
  #6%
}

\def\TestText(#1,#2,#3)(#4,#5)#6#7{%
% #1, #2, #3 = cyan, magenta and yellow components of the color filter,
% #4 = horizontal size, #5 = vertical size, #6 = random seed, #7 = text
\definecolor{ColorFilter}{cmyk}{#1,#2,#3,0}%
\dataheight=#4\relax
\begin{pspicture}(#4,#5)
  \randomi=#6\relax
  \GraphicBackground(#4,#5)%
  \multido{\iLineMOne=\z@+\@ne,\iLine=\@ne+\@ne}{#4}{%
    \multido{\iColumnMOne=\z@+\@ne,\iColumn=\@ne+\@ne}{#5}{%
      \psclip{\psframe[linestyle=none](\iLineMOne,\iColumnMOne)(\iLine,\iColumn)}
        \TextTransparent(#1,#2,#3)(\iLine,\iColumn){%
          \rput(0,0){\pscharpath[linestyle=none,fillstyle=solid,fillcolor=MyColor]{#7}}}
      \endpsclip}}
\end{pspicture}}

\makeatother

\begin{document}

\TestText(0.8,0.1,0.1)(8,6){574214204}{\rput[lb]{37}(2.5,-1){\bf\Rm\protect\TeX}}

\end{document}