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diff --git a/Master/texmf-dist/doc/latex/sciposter/sciposterexample/sciposter-example.tex b/Master/texmf-dist/doc/latex/sciposter/sciposterexample/sciposter-example.tex new file mode 100644 index 00000000000..2f5f294d46f --- /dev/null +++ b/Master/texmf-dist/doc/latex/sciposter/sciposterexample/sciposter-example.tex @@ -0,0 +1,342 @@ +\documentclass{sciposter} + + +\usepackage{epsfig} +\usepackage{amsmath} +\usepackage{amssymb} +\usepackage{multicol} +%\usepackage{fancybullets} + +\newtheorem{Def}{Definition} + +%\definecolor{BoxCol}{rgb}{0.9,0.9,0.9} +% uncomment for grey background to \section boxes +% for use with default option boxedsections + +%\definecolor{BoxCol}{rgb}{0.9,0.9,1} +% uncomment for light blue background to \section boxes +% for use with default option boxedsections + +%\definecolor{SectionCol}{rgb}{0,0,0.5} +% uncomment for dark blue \section text + + + + + + +\title{Generalized Pattern Spectra Sensitive to Spatial Information} + +% Note: only give author names, not institute +\author{Michael H. F. Wilkinson} + +% insert correct institute name +\institute{Institute for Mathematics and Computing Science,\\ + University of Groningen\\} + +\email{michael@cs.rug.nl} % shows author email address below institute + +%\date is unused by the current \maketitle + + +% The following commands can be used to alter the default logo settings +%\leftlogo[0.9]{logoWenI}{ % defines logo to left of title (with scale factor) +%\rightlogo[0.52]{RuGlogo} % same but on right + +% NOTE: This will require presence of files logoWenI.eps and RuGlogo.eps, +% or other supported format in the current directory +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +%%% Begin of Document + + + +\begin{document} +%define conference poster is presented at (appears as footer) + +\conference{{\bf ICPR 2002}, 16th International Conference on Pattern + Recognition, 11-15 August 2002, Qu\'ebec City, Canada} + + +\maketitle + +%%% Begin of Multicols-Enviroment +\begin{multicols}{3} + +%%% Abstract +\begin{abstract} +Morphological pattern spectra computed from granulometries are frequently used +to classify the size classes of details in textures and images. An extension +of this technique, which retains information on the spatial +distribution of the details in each size class is developed. Algorithms for +computation of these spatial pattern spectra for a large number of +granulometries on binary images are presented. +\end{abstract} + +%%% Introduction +\section{Introduction} + +\PARstart{G}{ranulometries} are ordered sets of morphological openings or closings, each of +which removes image details below a certain size. These can be used for texture +analysis +through the use of \emph{pattern spectra}, which show how the number of +foreground pixels in the image changes as a function of the size parameter +\cite{maragos89:_patter}. +A drawback of the classical definition of pattern spectra is that spatial +information is not included in a pattern spectrum as shown below. + In this paper, \emph{spatial pattern spectra} are developed which retain information on the distribution of these details at different scales. + + +\newcommand{\imsize}{0.45\columnwidth} +\begin{figure} +\begin{center} +\begin{tabular}{c c} +{\resizebox{\imsize}{!}{\includegraphics{blocks1}}} & +{\resizebox{\imsize}{!}{\includegraphics{blocks2}}}\\ +(a) & (b) \\ +{\resizebox{\imsize}{!}{\includegraphics{blocks3}}} & +{\resizebox{\imsize}{!}{\includegraphics{blocks1a}}}\\ +(c) & (d) \\ +\end{tabular} +\end{center} +\caption{ Parts (a) through (c) show three images consisting of squares of +different sizes; +(d) shows the pattern spectra, denoting the number of foreground pixels + removed by openings by reconstruction by $\lambda \times \lambda$ squares. No +granulometry is capable of separating the patterns, because the only +differences between the images lie in the distributions of the +connected components. }\label{fig:blocks} +\end{figure} + + + + +\section{Theory} + +Let binary images $X$ and $Y$ be defined as a subset of the image domain +${\mathbf M}\subset {\mathbb Z}^n$ or ${\mathbb R}^n$ (usually $n=2$). +\begin{Def} +A binary +granulometry is a set of operators $\{\alpha_r\}$ with $r$ from some ordered +set $\Lambda$ (usually $\Lambda \subset {\mathbb R}$ or ${\mathbb Z}$), with +the following three properties +\begin{align} + \alpha_r(X) & \subset X \label{eq:antiext} \\ + X \subset Y & \Rightarrow \alpha_r(X) \subset \alpha_r(Y) + \label{eq:increasing} \\ + \alpha_r(\alpha_s(X)) & = \alpha_{\max(r,s)}(X) \label{eq:idempot}, +\end{align} +for all $r,s \in \Lambda$. +\end{Def} + +\begin{Def} +The pattern spectrum $s_{\alpha}(X)$ obtained by applying +granulometry $\{\alpha_r\}$ to a binary image $X$ is defined as +\begin{equation} + (s_{\alpha}(X))(u) = + - \frac{\partial A(\alpha_r(X))}{\partial r}\bigg{\vert}_{r=u} +\end{equation} +in which $A(X)$ is a function denoting the Lebesgue measure in +${\mathbb R}^n$. +\end{Def} +In the case of discrete images, and with $r \in \Lambda \subset {\mathbb Z}$, +this differentiation reduces to +\begin{align} + (s_{\alpha}(X))(r) & = \#(\alpha_{r}(X) \setminus \alpha_{r^+}(X)) \\ + & = \#(\alpha_{r}(X)) - \#(\alpha_{r^+}(X)), +\end{align} +with $r^+ = \min\{ r' \in \Lambda \vert r' > r \}$, and $\#(X)$ the +numnber of elements of $X$. + +The opening transform \cite{Nacken:thesis} $\Omega_X$ of a binary image $X$ +for a granulometry ${\alpha_r}$ is +\begin{equation} + \Omega_X(x) = \max\{ r \in \Lambda \vert x \in \alpha_r(X) \} +\end{equation} + +The pattern spectrum of a binary image $X$ using granulometry +$\{\alpha_r\}$ is the histogram of $\Omega_X$ obtained with the same +size distribution \cite{Nacken:thesis}, disregarding the bin for grey level 0. + + +\begin{figure} +\begin{center} +{\resizebox{\imsize}{!}{\includegraphics{blocks3}}} +{\resizebox{\imsize}{!}{\includegraphics{blocks3rec}}} +\end{center} +\caption{ \label{fig:opentransf} Opening transform with $\{\alpha_r\}$ as in + Fig. \ref{fig:blocks}: (left) original image; (right) opening transform +(contrast stretched for clarity). +} +\end{figure} + + +\section{Spatial pattern spectra} +Pattern spectra only retain the amount of detail present at scale $r$. +This can be amended by computing some parameterization of the spatial +distribution in an image $\alpha_r(X) \setminus \alpha_{r+}(X)$ as a function of $r$. + +\begin{Def} +Let ${M}(X)$ be some parameterization of the spatial distribution of detail +in the image $X$. The spatial pattern spectrum ${S}_{{M},\alpha}$ is +then defined as +\begin{equation} + ({S}_{{M},\alpha}(X))(r) = {M}(\alpha_r(X) \setminus \alpha_{r+}(X)). +\end{equation} +\end{Def} + +An obvious parameterization of the spatial distribution is through +the use of moments. Focusing on the case of 2-D binary images, the +moment $m_{ij}$ of order $ij$ of an image $X$ is given by +\begin{equation} + m_{ij}(X) = \sum_{(x,y) \in \mathbf X} x^i y^j. +\end{equation} +The spatial moment spectrum $S_{m_{ij},\alpha}$ of order $ij$ is +\begin{equation} + (S_{m_{ij},\alpha}(X))(r) = m_{i,j}(\alpha_r(X) \setminus \alpha_{r^+}(X)). +\end{equation} +For $i=0$ and $j=0$ we obtain the standard pattern spectrum. +For each $r$, $(S_{m_{ij},\alpha}(X))(r)$ is just the moment of an image, +therefore, derived parameters such as coordinates of the centre of mass, +(co-)variances, skewness and kurtosis of the distribution of details at each +scale can be computed easily. We can then define pattern mean +spectra, pattern (co-)variance spectra, pattern kurtosis spectra, etc. The +pattern mean-$x$ and variance-$x$ spectra +($S_{\bar x,\alpha}$ and $S_{\sigma(x),\alpha}$) are defined as: +\begin{align} + S_{\bar x,\alpha} & = \frac{S_{m_{10},\alpha}} {S_{m_{00},\alpha}} \\ +\intertext{and} + S_{\sigma(x),\alpha} & = \sqrt{\frac{S_{m_{20},\alpha}} + {S_{m_{00},\alpha}} + - S_{\bar x, \alpha}}. + \end{align} +These two are shown in Figures \ref{fig:tauspect} and \ref{fig:binspect}. Note that +these definitions hold only where $(S_{m_{00},\alpha}(f))(r) \neq 0$. For all +other values of $r$ they will be defined as zero. Further post-processing can +be done to compute central moments and moment invariant from pattern moment +spectra \cite{Flusser:Suk:93,Hu:62}. + +\section{An Algorithm} + +Nacken \cite{Nacken:thesis} derived an algorithm for computation +of pattern spectra for granulometries based on openings by discs of increasing +radius for various metrics, using the opening transform. After the +opening transform has been computed, it is straightforward to compute the +pattern spectrum: +\begin{itemize} +\item Set all elements of array {\tt S} to zero +\item For all $x \in X$ increment {\tt S}[$\Omega_X(x)$] by one. +\end{itemize} + +To compute the pattern \emph{moment} spectrum, the only thing that needs to be +changed is the way {\tt S}[$\Omega_X(x)$] is incremented. As shown in Algorithm +\ref{alg:spect}. + +\begin{algorithm} +\begin{itemize} +\item Set all elements of array {\tt S} to zero +\item For all $(x,y) \in X$ increment {\tt S}[$\Omega_X(x,y)$] by +$x^iy^j$. +\end{itemize} +\caption{ Algorithm for computation of pattern moment +spectrum of order $ij$. \label{alg:spect}} +\end{algorithm} + +This algorithm can +readily be adapted to other granulometries, simply by computing the +appropriate opening transform. + +\begin{figure} +\begin{center} +\begin{tabular}{c c} +{\resizebox{\imsize}{!}{\includegraphics{blocks3op}}} & +{\resizebox{\imsize}{!}{\includegraphics{blocksopen3a}}}\\ +(a) & (b)\\ +{\resizebox{\imsize}{!}{\includegraphics{blocksopen3vx}}}& +{\resizebox{\imsize}{!}{\includegraphics{blocksopen3vy}}}\\ +(c) & (d) \\ +\end{tabular} +\end{center} +\caption{ \label{fig:tauspect} +The opening transform using city-block metric: (a) opening transform of +Fig. 1(c); (b) pattern spectrum; (c) pattern variance-$x$; +(d) variance-$y$ spectra.} +\end{figure} + + + + + + +\renewcommand{\imsize}{0.3\columnwidth} +\begin{figure} +\begin{center} +{\resizebox{\imsize}{!}{\includegraphics{blocks1mx}}} +{\resizebox{\imsize}{!}{\includegraphics{blocks2mx}}} +{\resizebox{\imsize}{!}{\includegraphics{blocks3mx}}}\\ +{\resizebox{\imsize}{!}{\includegraphics{blocks1vx}}} +{\resizebox{\imsize}{!}{\includegraphics{blocks1vx}}} +{\resizebox{\imsize}{!}{\includegraphics{blocks3vx}}} +\end{center} +\caption{ \label{fig:binspect} Pattern mean-$x$ (top) and variance-$x$ +(bottom) spectra: the three collumns show spectra for Fig. 1(a), (b) and (c) +from left to right respectively. Unlike the standard pattern spectra, +these spatial pattern spectra can distinguish the three images.} +\end{figure} + +\section{Discussion} +Spatial pattern spectra form a useful supplement to ordinary pattern +spectra, because of their ability to retain spatial information. +Pattern moment spectra, in particular, are easily computed concurrently with +computation of the standard pattern spectrum. Post-processing of these pattern +moment spectra can be done to yield a number of easily interpreted spectra, +such as pattern mean, variance, skew, and kurtosis spectra, which have reduced +covariance compared to the ``raw'' pattern moment spectra. Invariance to +rotation, translation or scale change can also be achieved by post-processing +\cite{Flusser:Suk:93,Hu:62}. + +In the future grey scale versions of these spatial pattern spectra will be +developed. I expect that the efficient grey level algorithms for area and +attribute pattern spectra +\cite{Meijster:Wilkinson:PAMI} +can be adapted to spatial pattern spectra as well. + +%%% References + +%% Note: use of BibTeX als works!! + +\bibliographystyle{plain} +\begin{thebibliography}{1} + +\bibitem{Flusser:Suk:93} +J.~Flusser and T.~Suk. +\newblock Pattern recognition by affine moment invariants. +\newblock {\em Pattern Recognition}, 26:167--174, 1993. + +\bibitem{Hu:62} +M.~K. Hu. +\newblock Visual pattern recognition by moment invariants. +\newblock {\em IRE Transactions on Information Theory}, IT-8:179--187, 1962. + +\bibitem{maragos89:_patter} +P.~Maragos. +\newblock Pattern spectrum and multiscale shape representation. +\newblock {\em IEEE Trans. Patt. Anal. Mach. Intell.}, 11:701--715, 1989. + +\bibitem{Meijster:Wilkinson:PAMI} +A.~Meijster and M.~H.~F. Wilkinson. +\newblock A comparison of algorithms for connected set openings and closings. +\newblock {\em IEEE Trans. Patt. Anal. Mach. Intell.}, 24(4):484--494, 2002. + +\bibitem{Nacken:thesis} +P.~F.~M. Nacken. +\newblock {\em Image Analysis Methods Based on Hierarchies of Graphs and + Multi-Scale Mathematical Morphology}. +\newblock PhD thesis, University of Amsterdam, Amsterdam, The Netherlands, + 1994. + +\end{thebibliography} + +\end{multicols} + +\end{document} + |