metrics, which is in $\theta(686)$. Computing the distance is thus in
$\theta(2\times 343^2)$ and this modification
is thus in $\theta(2\times 343^2 \times n^2)$.
-Ranking these results may be achieved with an insertion sort, which is in
-$2 \times n^2 \ln(n)$.
+Ranking these results may be achieved with a quick sort, which is in
+$\theta(2 \times n^2 \ln(n))$ for data of size $n^2$.
The overall complexity of the pixel selection is finally
$\theta(n^2 +2 \times 343^2 + 2\times 343^2 \times n^2 + 2 \times n^2 \ln(n))$, \textit{i.e},
$\theta(2 \times n^2(343^2 + \ln(n)))$.
\begin{center}
\includegraphics[scale=0.4]{complexity}
\end{center}
-\caption{Complexity evaluation of WOW/UNIWARD, HUGO, and STABYLO}
+\caption{Complexity evaluation of WOW/UNIWARD, HUGO, and STABYLO.}
\label{fig:compared}
\end{figure}
