\ctsimfooter%
-\section{Overview}\index{Graphical shell}
+\section{Overview}\index{Graphical interface}
\ctsim\ is the graphical shell for the CTSim project. This shell uses
the \urlref{wxWindows}{http://www.wxwindows.org} library for
cross-platform compatibility. The graphical shell is compatible
frequency domain as their natural domain.}
\twocolitem{\textbf{X Size}}{Number of columns in the output image.}
\twocolitem{\textbf{Y Size}}{Number of rows in the output image.}
-\twocolitem{\textbf{Hamming Parameter}}{Sets the parameter for the Hamming filter.}
+\twocolitem{\textbf{Hamming Parameter}}{ This parameter adjusts the smoothing of the Hamming
+filter and can range from \texttt{0} to \texttt{1}.
+At a setting of \texttt{1}, the Hamming filter is the same as the bandlimit filter.
+At a setting of \texttt{0.54}, the Hamming filter is the same as the Hanning
+window.}
\twocolitem{\textbf{Bandwidth}}{Sets the bandwidth of the filter.}
\twocolitem{\textbf{Axis (input) Scale}}{Sets the scale for the filter input. By default, the input to the filter is
the distance in pixels from the center of the image. By changing this value, one can set a scale the input to the filter.
\end{twocollist}
-\subsection{View}\label{intensityscale}\index{Intensity Scale}
+\subsection{View}\label{intensityscale}\index{Intensity scale}
These commands are used change the intensity scale for viewing the image.
These commands do not change the image data. When the minimum intensity is
set, then the color pure black is assigned to that image intensity. Similarly,
\item Color scale on or off.
\end{itemize}
-\subsection{Filter}\index{Image filter}
+\subsection{Filter}\index{Image!Filter}
These commands filter and modify the image
\subsubsection{Arithmetic}
have options for converting a complex-valued image into a real-valued image via
the \texttt{Magnitude} and \texttt{Phase} filtering commands.
+
\subsection{Analyze}
These commands are used for analyzing an image.
also exists for generating a difference image from the two input images.
There are also commands for comparison plotting of rows and columns from two images.
- This is quite helpful when comparing a phantom to a reconstruction.
+This is quite helpful when comparing a phantom to a reconstruction.
+
+The three distance measures 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.}
+\end{twocollist}
\section{Projection Menus}
The displayed properties include:
\begin{itemize}
-\item Number of detectors in the projections
-\item Number of views
-\item The variables used when generating the projections from the phantom
+\item Number of detectors in the projections.
+\item Number of views.
+\item The variables used when generating the projections from the phantom.
\end{itemize}
\subsection{Process - Convert Polar Dialog}\label{IDH_DLG_POLAR}\index{Polar conversion}
Creates an image file with the polar conversion of the projection data. The options to set are:
\begin{twocollist}
-\twocolitem{\textbf{xsize}}{Number of columns in output image.}
-\twocolitem{\textbf{ysize}}{Number of rows in output image.}
-\twocolitem{\textbf{interpolation}}{Selects the interpolation method.
+\twocolitem{\textbf{X Size}}{Number of columns in output image.}
+\twocolitem{\textbf{Y Ssize}}{Number of rows in output image.}
+\twocolitem{\textbf{Interpolation}}{Selects the interpolation method.
Currently, the \texttt{bilinear} option provides the highest
quality interpolation.}
\end{twocollist}
\subsection{Process - Convert FFT Polar Dialog}
-The parameters for this option are the same as \helprefn{Convert
+The parameters for this option are the same as the \helprefn{Convert
Polar Dialog}{convertpolardialog}. For this command, though, the
projections are Fourier transformed prior to conversion to polar
image.
\subsection{Reconstruct - Filtered Backprojection Dialog}\label{IDH_DLG_RECONSTRUCTION}\index{Dialog!Reconstruction}
This dialog sets the parameters for reconstructing an image from projections
-using the Filtered Backprojection technique.
-
+using the filtered backprojection technique. The parameters available are:
\begin{twocollist}
\twocolitem{\textbf{Filter}}{Selects which filter to apply to each
\item \texttt{abs\_bandlimit}
\item \texttt{abs\_cosine}
\item \texttt{abs\_hamming}
+\item \texttt{abs\_hanning}
\end{itemize}
} \twocolitem{\textbf{Hamming parameter}}{Sets the alpha level for
-Hamming window. At setting of 0.54, this equals the Hanning
+Hamming window. This parameter adjusts the smoothing of the Hamming
+filter and can range from \texttt{0} to \texttt{1}.
+At a setting of \texttt{1}, the Hamming filter is the same as the bandlimit filter.
+At a setting of \texttt{0.54}, the Hamming filter is the same as the Hanning
window.}
-
\twocolitem{\textbf{Filter Method}}{Selects the filtering method.
-For large numbers of detectors, \texttt{rfftw} is optimal. For
-smaller numbers of detectors, \texttt{convolution} might be a bit
-faster.
-\begin{itemize}\itemsep=0pt
-\item \texttt{convolution}
-\item \texttt{fourier} - Uses simple Fourier transform.
-\item \texttt{fourier-table} - Optimizes Fourier transform by precalculating trigometric functions.
-\item \texttt{fftw} - Uses complex-valued Fourier transform with the \emph{fftw} library.
-\item \texttt{rfftw} - Uses optimized real/half-complex Fourier transform.
-\end{itemize}
+For large numbers of detectors, the FFT-based filters are preferred whereas for
+smaller numbers of detectors \texttt{convolution} can be
+faster. When \emph{Advanced Options} have been turned off, this menu only shows
+the two basic choices: \texttt{convolution} and \texttt{FFT}. However, when
+\emph{Advanced Options} have been turned on, additional selections are available as
+discussed in the next section.
}
-
\twocolitem{\textbf{Interpolation}}{Interpolation technique.
\texttt{cubic} is optimal when the
data is smooth. Smooth data is obtained by taking many projections and/or
using a smoothing filter. In the absence of smooth data, \texttt{linear} gives better results and
-is many times faster than cubic interpolation.
+is also many times faster than cubic interpolation.
\begin{itemize}\itemsep=0pt
\item nearest
by expert users.
\begin{twocollist}
+\twocolitem{\textbf{Filter Method}}{Selects the filtering method.
+The general comments about this parameter given the previous section still apply.
+With \emph{Advanced Options} on, the full set of filter methods are available:
+\begin{itemize}\itemsep=0pt
+\item \texttt{convolution}
+\item \texttt{fourier} - Uses simple Fourier transform.
+\item \texttt{fourier-table} - Optimizes Fourier transform by precalculating trigometric functions.
+\item \texttt{fftw} - Uses complex-valued Fourier transform with the \emph{fftw} library.
+\item \texttt{rfftw} - Uses optimized real/half-complex Fourier transform.
+\end{itemize}
+}
\twocolitem{\textbf{Backprojection}}{Selects the backprojection
technique. A setting of \texttt{idiff} is optimal.
\begin{itemize}\itemsep=0pt
\item \texttt{trig} - Use trigometric functions at each image point.
\item \texttt{table} - Use precalculated trigometric tables.
\item \texttt{diff} - Use difference method to iterate within image.
-\item \texttt{idiff} - Use integer iteration math.
+\item \texttt{idiff} - Use integer iteration techique.
\end{itemize}
}
\twocolitem{\textbf{Zeropad}}{Zeropad factor when using
frequency-based filtering. A setting of \texttt{1} is optimal whereas
-a setting of \texttt{0} disables zero padding.}
+a setting of \texttt{0} disables zero padding. Settings greater than \texttt{1}
+perform larger amounts of zero padding but without any significant benefit.}
\end{twocollist}
\begin{itemize}\itemsep=0pt
\item the number of curves in the plot and the number of points per curve.
\item the EZPlot commands used to format the plot are displayed.
-\item history labels from the originating image(s) and the plot function
+\item history labels from the originating image(s) and the plot function.
\end{itemize}
\subsection{View Menu}
projects / ctsim.git / blobdiff