It appears that dx and dy
define the end points of a radius of the sector, from which the radius and
the angle of the two arms of the sector are calculated. But then
-orientation and centreing of the sector don't make much sense yet.
+orientation and centering of the sector don't make much sense yet.
\subsubsection{segment}
Segments are the segments of a circle between a chord and the
\subsection{Phantom Size}
Also note that the overall dimensions of the phantom are increased by 1\%
-above the specified sizes to avoid clipping due to round-off errors. If the phantom is defined as
+above the specified sizes to avoid clipping due to round-off errors.
+So, if the phantom is defined as
a rectangle of size 0.1 by 0.1, the actual phantom has extent $\pm$0.101 in
each direction.
as the standard length scale. Remember, as mentioned above, the
phantom dimensions are also padded by 1\%.
-The maximum of the phantom length and height is used as the phantom
-dimension, and one can think of a square bounding box of this size
-which completely contains the phantom. Let $l_p$ be the width (or height)
-of this square.
+The maximum of the phantom length and height is used to define the square
+that completely surrounds the phantom. Let $p_l$ be the width (also height)
+of this square. The diameter of this boundary box, $p_d$ is then
+\latexonly{\begin{equation}p_d = \sqrt{2} (p_l/2)\end{equation}}
+\latexignore{sqrt(2) * $p_l$.}
+This relationship can be seen in figure 1.
\subsubsection{Focal Length \& Field of View}
-The two other important variables are the field-of-view-ratio ($f_{vR}$)
-and the focal-length-ratio ($f_{lR}$). These are used along with $l_p$ to
-define the focal length and the field of view (not ratios) according to
-\latexonly{\begin{equation}
-f_l = \sqrt{2} (l_p/2)(f_{lR})= (l_p/\sqrt{2}) f_{lR}
-\end{equation}
-\begin{equation}
-f_v = \sqrt{2}l_p f_{vR}
-\end{equation}}
-So the field of view ratio is specified in units of the phantom diameter,
-whereas the focal length is specified in units of the phantom radius. The
-factor of
-\latexonly{$\sqrt(2)$}
-\latexignore{sqrt(2)}
-can be understood if one refers to figure 1, where
+The two important variables is the focal-length-ratio $f_lr$.
+This is used along with $p_d$ to
+define the focal length according to
+\latexonly{\begin{equation}f_l = f_lr p_d\end{equation}}
+\latexignore{$f_l$ = $f_lr$ x $p_d$\\}
+where
we consider the case of a first generation parallel beam CT scanner.
\subsubsection{Parallel Geometry}\label{geometryparallel}\index{Concepts,Scanner,Geometries,Parallel}
\section{Image Menus}
\subsection{File - Properties}
\subsection{View}
+
\subsection{Image}
These commands create a new image.
+
\subsection{Filter}
These commands filter image.
\subsection{Anaylze}
\section{Projection Menus}
-\subsection{Convert Polar Dialog}
-\subsection{Convert FFT Polar Dialog}
-\subsection{Filtered Backprojection Dialog}
+\subsection{Process - Convert Polar Dialog}\label{convertpolardialog}
+The parameters are \texttt{xsize}, \texttt{ysize}, and \texttt{interpolation}.
+The \texttt{xsize} and \texttt{ysize} parameters set the size of the
+resulting image file. The \texttt{interpolation} parameter selects the
+interpolation method. Currently, the \texttt{bilinear} option provides
+the highest quality interpolation.
+
+\subsection{Process - Convert FFT Polar Dialog}
+The paramters for this option are the same as
+\helprefn{convertpolardialog}{Convert Polar Dialog}. For this command,
+though, the projections are Fourier transformed prior to conversion to
+polar image.
+
+\subsection{Reconstruct - Filtered Backprojection Dialog}
+This dialog sets the parameters for reconstructing an image from projections
+using the Filtered Backprojection technique. The parameters are identical
+to those for the \helprefn{pjrec}{pjrec} program.
\section{Plot Menus}
\subsection{File - Properties}
\section{Web Requirements}\label{installreq}\index{Installation,Requirements}%
\begin{itemize}
- \item zlib Library (optional)
- \par Used for PNG file export.
+ \item zlib Library (optional)\\
+ Used for PNG file export.
- \item libpng Library (optional)
- \par Used for PNG file export.
- \par www.libpng.org
+ \item libpng Library (optional)\\
+ Used for PNG file export.\\
+ www.libpng.org
- \item FFTW library (optional)
- \par Used for frequency-based filtering and fourier transformations of images.
- \par www.fftw.org
+ \item FFTW library (optional)\\
+ Used for frequency-based filtering and fourier transformations of images.\\
+ www.fftw.org
- \item readline library (optional)
- \par Used for \ctsimtext interactive shell.
+ \item readline library (optional)\\
+ Used for \ctsimtext\ interactive shell.
- \item dmalloc library (optional)
- \par Used for debugging memory allocation
- \par www.dmalloc.com
+ \item dmalloc library (optional)\\
+ Used for debugging memory allocation\\
+ www.dmalloc.com
- \item wxWindows library (optional)
- \par Used for platform-independent graphical interface. The graphical-shell
- program \ctsim\ requires this library.
- \par www.wxwindows.org
+ \item wxWindows library (optional) \\
+ Used for platform-independent graphical interface. The graphical-shell
+ program \ctsim\ requires this library.\\
+ www.wxwindows.org
\end{itemize}
\usepackage{graphicx}
\usepackage{texhelp}
\usepackage{fancyhea}
-\usepackage{mysober}
+%\usepackage{mysober}
\usepackage{mytitle}
-\usepackage{verbatim}
+%\usepackage{verbatim}
\usepackage{makeidx}
-\usepackage{times}
+%\usepackage{times}
\usepackage{hyperref}
\input{psbox.tex}
Copyright (c) 1983-2001 Kevin Rosenberg, M.D.
-Specified file
-
Permission to use, copy, modify, and distribute this software and its
documentation for any purpose is hereby granted without fee, provided that the
above copyright notice, author statement and this permission notice appear in
\rtfsp\ctsim\ can then reconstruct the interior of the object from the projections
collected around the phantom object.
-The \ctsim\ package has two executable files: the graphical \helprefn{ctsim}{ctsim} and text \helprefn{ctsimtext}{ctsimtext} programs.
+The \ctsim\ package has two executable files: the graphical
+\helprefn{ctsim}{ctsim} and text \helprefn{ctsimtext}{ctsimtext} programs.
\include{ctsim-concepts}
projects / ctsim.git / commitdiff