The operation of \ctsim\ begins with the phantom object. A
phantom object consists of geometric elements. A scanner is
specified and the collection of x-ray data, or projections, is
-simulated. That projection data can be reconstructed using various
+simulated. This projection data can be reconstructed using various
user-controlled algorithms producing an image of the phantom
object. These reconstructions can be visually and statistically
compared to the original phantom object.
\subsubsection{ellipse}
Ellipses use \texttt{dx} and \texttt{dy} to define the semi-major and
-semi-minor axis lengths, with the center of the ellipse at \texttt{(cx,cy)}.
+semi-minor axis lengths with the center of the ellipse at \texttt{(cx,cy)}.
Of note, the commonly used phantom described by
Shepp and Logan\cite{SHEPP74} uses only ellipses.
and \texttt{dy} are the half-width and half-height of the rectangle.
\subsubsection{triangle}
-Triangles are drawn with the center of the base at \texttt{(cx,cy)},
-with a base half-width of \texttt{dx} and a height of \texttt{dy}.
+Triangles are drawn with the center of the base at \texttt{(cx,cy)
+and a base half-width of \texttt{dx} and a height of \texttt{dy}.
Rotations are then applied about the center of the base.
\subsubsection{segment}
being a very flexible simulator, gives tremendous options in
setting up the geometry for a scan.
-In general, the geometry for a scan all starts with the size of
+The geometry for a scan starts with the size of
the phantom being scanned. This is because \ctsim\ allows for
statistical comparisons between the original phantom image and
it's reconstructions. Since CT scanners scan a circular area, the
by \ctsim. They are taken from the standard measurements used by
Herman\cite{HERMAN80}. They are:
-\begin{twocollist}
-\twocolitem{\textbf{$d$}}{The normalized root mean squared distance measure.}
-\twocolitem{\textbf{$r$}}{The normalized mean absolute distance measure.}
-\twocolitem{\textbf{$e$}}{The worst case distance measure over a \latexonly{$2\times2$}\latexignore{\emph{2 x 2}} pixel area.}
+\begin{itemize}\itemsep=0pt
+\item[-]\textbf{$d$}\quad The normalized root mean squared distance measure.
+\item[-]\textbf{$r$}\quad The normalized mean absolute distance measure.
+\item[-]\textbf{$e$}\quad The worst case distance measure over a \latexonly{$2\times2$}\latexignore{\emph{2 x 2}} pixel area.
\end{twocollist}
These measurements are defined in equations \ref{dequation} through \ref{bigrequation}.
automatically open. \ctsim\ can open projection files, image
files, phantom files, and plot files.
+On Microsoft Windows platforms, the simplest way to invoke \ctsim\ is
+via the \emph{Start} menu under the \emph{Programs} sub-menu.
+
+\section{Quick Start}\label{quickstart}\index{Quick Start}
\section{File Types}\index{File types}
create and edit these files.
\subsection{Image}
-Image files are 2-dimensional files that store 4-byte floating
+Image files contain 2-dimensional arrays that store 4-byte floating
point values. Images files can be either real or complex-valued.
Typically, all images are real-valued except for images that have been
processed by Fourier transforms. As you might expect,
\chapter*{Copyright notice}%
\setheader{{\it COPYRIGHT}}{}{}{\ctsimheadtitle}{}{{\it COPYRIGHT}}%
-\setfooter{\thepage}{}{}{}{\manver}{\thepage}%
+\ctsimfooter
Copyright (c) 1983-2001 Kevin Rosenberg, M.D.
OF LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
PERFORMANCE OF THIS SOFTWARE.
+
\chapter*{Acknowledgements}
\setheader{{\it COPYRIGHT}}{}{}{\ctsimheadtitle}{}{{\it COPYRIGHT}}%
\setfooter{\thepage}{}{}{}{\manver}{\thepage}%
\textbf{Ian Kay, Ph.D.}\\
-Dr. Kay has contributed portions to this manual. He has also assisted the
-development of \ctsim\ with his bug reports and fixes.
+Special thanks to Dr. Kay for contributing portions to this manual. Dr. Kay has assisted the
+development of \ctsim\ with bug reports and fixes.
\textbf{Gabor T. Herman, Ph.D.}\\
-Dr. Herman's publications on computed tomography provided me with my initial inspiration
-to create \ctsim\ back in 1983. Dr. Herman has graciously permitted use of his
+Dr. Herman's publications on computed tomography inspired me to
+create the initial version \ctsim\ in 1983. Dr. Herman
+has graciously permitted use of his
copyrighted head phantom for use in \ctsim.
\centerline{\image{3cm;3cm}{logo-huge.eps}}
-Computed Tomography is a technique for estimating the interior of an
-object from measurement of radiation collected around the object. This
+Computed tomography is a technique for estimating the interior of an
+object from measurements of radiation collected around the object. This
radiation can be either projected through or emitted from the
object. \ctsim\ simulates the process of projecting X-rays
through a phantom object. \ctsim\ can then reconstruct the
projects / ctsim.git / commitdiff