to start Terascan
Functions and GUIs
Terascan is used for mapping and gridding and
for calibration of the satellite data. There are commands for the
direct injestion of raw level 1B data into Terascan.
How to start
Two versions of Terascan (2.6
and 3.1) are installed in this department.
To start terascan 2.6, type
terascan on a xterm, a new xterm titled terascan 2.6 will
To start terascan 3.1, type
ts31 on a xterm, a new xterm titled terascan 3.1 will come
All the terascan command-line
functions and Graphic User Interfaces (GUIs) should be used under
the terascan environment.
Notice : You may need to shell to computer ashcloud
first, because of color demands.
Functions and GUIs
Help for terascan command-line
functions can be found at TeraScan
Online Reference Manual. Online help is also available by
entering man command.
Terascan has several Graphical
User Interfaces, information about terascan GUIs can be found at
Online Reference Manual under the "What is TeraScan ?".
Three terascan GUIs, xvu,
tvis and tmaster, may be of particular interest to
xvu is the GUI for displaying
and manipulating data. To start xvu from the command line, enter
tvis has capabilities similar
to those of xvu, but uses a fancier interface. To start tvis from
the command line, enter tvis &.
tmaster is a GUI for viewing,
creating, and modifying masters. To start tmaster from the
command line, enter tmaster &.
Notice : It is better to start xvu first,
otherwise there may not be enough colors left for xvu.
Masters are used in Terascan for three purposes:
As a base map to which the
sensor view of the data is corrected to an earth-located view of
the data, a process known as registration.
As a criterion for scheduling
pass capture. Satellite passes are scheduled for capture only if
the satellite reaches a specified minimum elevation relative to
the center of the area defined by the master.
To delimit a subset of data
from a whole pass for processing, instead of processing the
entire pass. In this case, data processing is limited to a
line-by-sample rectangle of data sufficient to encompass the
area defined by the master.
To create a master file, use the command-line finction
master or GUI tmaster.