\begin{table} %T2 
%\centering
\small
\caption{Theoretical fractal dimension $D_{\rm th}$, measured 
fractal dimension~$D$ for the studied objects and 
the relative error $\epsilon=(D_{\rm th}-D)/D_{\rm th}$. Pixelization errors increase with
increasing structure complexity. 
  }\label{pixparset}
\begin{tabular}{ccrr}                                        
\hline\hline
$   $ & $D_{\rm th}$  & \multicolumn{1}{c}{$D$}   &  \multicolumn{1}{c}{$\epsilon$}  \\
\hline
fBm & $1.8$     & $1.516$  &    $16 \%$ \\
fBm & $1.6$     & $1.413 $  &    $12 \%$ \\
vonKnoch & $1.26$    & $1.310$  &    $-3 \%$\\                        
\hline
\end{tabular}
\end{table}