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Commit 571fb9cc authored by Jordi Inglada's avatar Jordi Inglada
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Restructuration sections exemples moments

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......@@ -12,10 +12,9 @@ What is feature extraction
\subsection{Lines}
\subsection{Geometric Moments}
Using the algebraic moment theory, H. Ming-Kuel obtained a family of 7
invariants with respect to planar transformations called Hu invariants,
\cite{hu}. Those invariants can be seen as nonlinear combinations of
complex geometric moments:
\subsubsection{Complex Moments}
\label{sec:ComplexMoments}
The complex geometric moments are defined as:
\begin {equation}
c_{pq} = \int\limits_{-\infty}^{+\infty}\int\limits_{-\infty}^{+\infty}(x + iy)^p(x- iy)^qf(x,y)dxdy,
\label{2.2}
......@@ -23,7 +22,18 @@ c_{pq} = \int\limits_{-\infty}^{+\infty}\int\limits_{-\infty}^{+\infty}(x + iy)^
where $x$ and $y$ are the coordinates of the image $f(x,y)$, $i$ is the
imaginary unit and
$p+q$ is the order of $c_{pq}$. The geometric moments are
particularly useful in the case of scale changes. Hu invariants have
particularly useful in the case of scale changes.
\input{ComplexMomentImageExample}
\textbf{Example with paths}
%\input{ComplexMomentPathExample}
\subsubsection{Hu Moments}
\label{sec:HuMoments}
Using the algebraic moment theory, H. Ming-Kuel obtained a family of 7
invariants with respect to planar transformations called Hu invariants,
\cite{hu}. Those invariants can be seen as nonlinear combinations of
the complex moments. Hu invariants have
been very much used in object recognition during the last 30 years,
since they are invariant to rotation, scaling and translation. \cite{flusserinv} gives their expressions :
......@@ -37,7 +47,16 @@ since they are invariant to rotation, scaling and translation. \cite{flusserinv}
\cite{dudani} have used these invariants for the recognition of
aircraft silhouettes. Flusser and Suk have used them for image
registration, \cite{flusser_2}. They have been modified and
registration, \cite{flusser_2}.
\textbf{Examples}
%\input{HuMomentImageExample}
%\input{HuMomentPathExample}
\subsubsection{Flusser Moments}
\label{sec:FlusserMoments}
The Hu invariants have been modified and
improved by several authors. Flusser used these moments in order to
produce a new family of descriptors of order higher than 3,
\cite{flusserinv}. These descriptors are invariant to scale and
......@@ -53,14 +72,8 @@ rotation. They have the following expressions:
\end{array}
\end {equation}
OTB allows the computation of complex moments and Flusser and Hu
moments, and those can be computed on images and paths.
\textbf{Mettra a jour quand la classe sera corrigee}
\input{ComplexMomentImageExample}
%% \input{ComplexMomentFunctionExample}
%% \input{FlusserMomentImageExample}
%% \input{FlusserMomentFunctionExample}
\textbf{Examples}
%\input{FlusserMomentImageExample}
%\input{FlusserMomentPathExample}
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