X-Git-Url: http://git.kpe.io/?p=ctsim.git;a=blobdiff_plain;f=doc%2Fctsim-concepts.tex;h=12cdc3f603942ad4ccc1abfe63b1bb3d912e81b7;hp=29a0fad3b1d294fc0f2819c0c22ced9fd42a3f35;hb=3b389ec4d6e6c5a720ea096b8f504e02b984d237;hpb=4ab75eaf538f5b42cf86830e44eee70590cd8c9a

diff --git a/doc/ctsim-concepts.tex b/doc/ctsim-concepts.tex
index 29a0fad..12cdc3f 100644
--- a/doc/ctsim-concepts.tex
+++ b/doc/ctsim-concepts.tex
@@ -119,10 +119,6 @@ length}. These variables are input into \ctsim\ in terms of
 ratios rather than absolute values.
 
 \subsubsection{Phantom Diameter}\index{Phantom!Diameter}
-\begin{figure}
-$$\image{5cm;0cm}{scangeometry.eps}$$
-\caption{\label{phantomgeomfig} Phantom Geometry}
-\end{figure}
 The phantom diameter is automatically calculated by \ctsim\ from
 the phantom definition. The maximum of the phantom length and
 height is used to define the square that completely surrounds the
@@ -134,9 +130,13 @@ Pythagorean theorem and is
 \latexonly{\begin{equation}p_d = p_l \sqrt{2}\end{equation}}
 CT scanners collect projections around a
 circle rather than a square. The diameter of this circle is
-the diameter of the boundary square \latexonly{$p_d$.  These
-relationships are diagrammed in figure~\ref{phantomgeomfig}.}
-\latexignore{emph{Pd}.}
+the diameter of the boundary square \latexonly{$p_d$.}
+\latexignore{\emph{Pd}.}
+\latexonly{These relationships are diagrammed in figure~\ref{phantomgeomfig}.}
+\begin{figure}
+\centerline{\image{5cm;0cm}{scangeometry.eps}}
+\latexonly{\caption{\label{phantomgeomfig} Phantom Geometry}}
+\end{figure}
 
 \subsubsection{View Diameter}\index{View diameter}
 The \emph{view diameter} is the area that is being processed
@@ -194,7 +194,7 @@ physically impossible and it analagous to have having the x-ray
 source inside of the \emph{view diameter}.
 
 
-\subsection{Parallel Geometry}\label{geometryparallel}\index{Parallel geometry}
+\subsection{Parallel Geometry}\label{geometryparallel}\index{Parallel geometry}\index{Scanner!Parallel}
 
 The simplest geometry, parallel, was used in \mbox{$1^{st}$} generation
 scanners. As mentioned above, the focal length is not used in this simple
@@ -208,6 +208,7 @@ significant distortions will occur.
 
 
 \subsection{Divergent Geometries}\label{geometrydivergent}\index{Equilinear geometry}\index{Equiangular geometry}
+\index{Scanner!Equilinear}\index{Scanner!Equiangular}
 \subsubsection{Overview}
 Next consider the case of equilinear (second generation) and equiangular
 (third, fourth, and fifth generation) geometries. In these cases,
@@ -217,8 +218,8 @@ source produces a fan beam which is read by a linear array of detectors.  If
 the detectors occupy an arc of a circle, then the geometry is equiangular.
 \latexonly{These configurations are shown in figure~\ref{divergentfig}.}
 \begin{figure}
-\image{10cm;0cm}{divergent.eps}
-\caption{\label{divergentfig} Equilinear and equiangular geometries.}
+\centerline{\image{10cm;0cm}{divergent.eps}}
+\latexonly{\caption{\label{divergentfig} Equilinear and equiangular geometries.}}
 \end{figure}
 
 
@@ -231,11 +232,11 @@ the \emph{focal length}:
 \latexignore{\centerline{\emph{alpha = 2 x asin (
 (Sd / 2) / f)}}}
 \latexonly{\begin{equation}\label{alphacalc}\alpha = 2 \sin^{-1}
-((s_d / 2) / f)\end{equation}
- This is illustrated in figure~\ref{alphacalcfig}.}
+((s_d / 2) / f)\end{equation}}
+\latexonly{This is illustrated in figure~\ref{alphacalcfig}.}
 \begin{figure}
-\image{10cm;0cm}{alphacalc.eps}
-\caption{\label{alphacalcfig} Calculation of $\alpha$}
+\centerline{\image{10cm;0cm}{alphacalc.eps}}
+\latexonly{\caption{\label{alphacalcfig} Calculation of $\alpha$}}
 \end{figure}
 
 
@@ -282,13 +283,15 @@ the \emph{scan diameter} increases the detector array size.
 
 For equiangular geometry, the detectors are spaced around a circle
 covering an angular distance of
-\latexonly{$2\,\alpha$.}\latexignore{\emph{2 \alpha}.} The dotted
-circle in
+\latexonly{$2\,\alpha$.}\latexignore{\emph{2 \alpha}.}
+The dotted circle
+\latexonly{in figure~\ref{equiangularfig}}
+indicates the positions of the detectors in this case.
+
 \begin{figure}
-\image{10cm;0cm}{equiangular.eps}
-\caption{\label{equiangularfig}Equiangular geometry}
+\centerline{\image{10cm;0cm}{equiangular.eps}}
+\latexonly{\caption{\label{equiangularfig}Equiangular geometry}}
 \end{figure}
-figure~\ref{equiangularfig} indicates the positions of the detectors in this case.
 
 For equilinear geometry, the detectors are space along a straight
 line. The length of the line depends upon
@@ -296,11 +299,11 @@ line. The length of the line depends upon
 length}. It is calculated as
 \latexonly{\begin{equation}4\,f \tan (\alpha / 2)\end{equation}}
 \latexignore{\\\centerline{\emph{4 x F x tan(\alpha/2)}}}
+\latexonly{This geometry is shown in figure~\ref{equilinearfig}.}
 \begin{figure}\label{equilinearfig}
-\image{10cm;0cm}{equilinear.eps}
-\caption{\label{equilinearfig} Equilinear geometry}
+\centerline{\image{10cm;0cm}{equilinear.eps}}
+\latexonly{\caption{\label{equilinearfig} Equilinear geometry}}
 \end{figure}
-\latexonly{This geometry is shown in figure~\ref{equilinearfig}.}
 
 
 \section{Reconstruction}\label{conceptreconstruction}\index{Reconstruction Overview}%
@@ -347,7 +350,7 @@ Backprojection is the process of ``smearing'' the filtered
 projections over the reconstructing image. Various levels of
 interpolation can be specified.
 
-\section{Image Comparison}\index{Image comparison}
+\section{Image Comparison}\label{conceptimagecompare}\index{Image!Comparison}
 Images can be compared statistically. Three measurements can be calculated
 by \ctsim. They are taken from the standard measurements used by
 Herman\cite{HERMAN80}. They are: