The TeraScan Graphical User Interfaces
The TeraScan Graphical User Interfaces |
The TeraScan suite of graphical user interfaces includes:
TeraCapCon stands for TeraScan Capture Control. The TeraCapCon GUI is used for programming the TeraScan system to automatically capture and archive data coming via direct broadcast from satellite. Data-capture programming can also include links to automatic data processing.
Note: Although the TeraCapCon GUI is available on all systems and can be used for viewing polar-satellite coverage and overpass times, the capture-scheduling capabilities of TeraCapCon are available only to systems which have been licensed for the Data Capture Package.
From TeraCapCon, the user can:
- Define the autoscheduling rules that govern the daily updates of the pass-capture schedule.
- Modify the pass-capture schedule, if necessary, by adding, deleting, or editing pass records. This is one means of resolving scheduling conflicts flagged by TeraCapCon.
- View coverages for polar-orbiting passes at their home receiving site or at other receiving sites.
The autoscheduling rules that govern pass-capture scheduling can include these criteria for selecting passes:
- Specific satellites for a given telemetry.
- For polar-orbiting satellites, minimum satellite elevation at the satellite's highest point relative to the receiving site, or to another specified target.
- Minimum sun elevation (for polar-orbiting satellites).
- For geostationary satellites, selected time windows.
The autoscheduling rules can also dictate:
- The time of day when the schedule is to be updated.
- The number of days of passes to be scheduled.
- Whether or not passes are to be archived on tape.
- A processing script to be run on the data, which can include TeraScan functions for automatic product generation.
Note: XCapCon, the original TeraScan X windows capture and control GUI with capabilities similar to those of TeraCapCon, is also still available in TeraScan.
Graphic overview of PGS processing.
TeraPGS is a system for automatically generating and distributing products according to user specifications. TeraPGS handles multiple telemetries and can generate and deliver both TDF datasets and picture products. The picture products can have any of the following formats: TIFF, JPEG, METOC-TIFF (JIF), PNG, MARTA-PCX, PostScript, GIF.
TeraPGS consists of three main components: the GUI, the product-generation scripts, and the distributor.
The TeraPGS Graphical User Interface
The TeraPGS GUI enables you to configure, edit, and store product definitions. Each definition can prescribe a TDF dataset and up to three picture representations of the data to be generated from a given satellite telemetry.
Product definitions can dictate:
- Data selection by telemetry and variable, by time window, by geographic coverage, and by minimum sun elevation.
- For TDF datasets, any or all of the variables of a telemetry, as well as any synthesized variables (such as multi-channel sea surface temperatures).
- Options for picture products: automatic or manual data scaling; map, grid, and wedge overlays, and custom legend overlays; data overlays such as TOVS or GRIB contours, vectors, wind flags, marker plots, or stream plots; data unit, palette, and enhancement selection
- Delivery destinations and times, which can be different for each product.
- Notification of delivery success and/or failure.
Picture definitions can be tested via the GUI's dry-run feature, which enables the product to be generated and displayed locally with no delivery.
The TeraPGS Processing Scripts
The TeraPGS processing scripts generate products (either datasets or picture products) according to the product definitions set up from the TeraPGS GUI. Processing progress is logged and e-mail notifications of failures are issued.
The TeraPGS Distributor
The distributor is a daemon that manages asynchronous, non-blocking delivery of products. This means that delivery is independent of the time of product generation and doesn't interfere with product generation. The distributor has these features:
- Delivery of up to 50 products at a time to multiple recipients.
- Delivery by one of three means - FTP, copying, or remote copying - with file naming handled via a template that allows for numerous naming options.
- Retry capability and the option for notification of success or failure.
- Delivery-attempt options, including time windows for transmission of products, maximum number of tries, and time-outs.
- Options for post-delivery scrubbing of local directories.
Graphic overview of PGS processing.
PGS Express is a subset of TeraPGS that invokes custom scripts to generate products and then automatically distributes those products. PGS Express handles multiple telemetries (data streams) and can deliver either a dataset (TDF and HDF) or a picture product (GIF, GTIF, JPG, MIFF, PCX, PNG, and TIFF).
PGS Express consists of two GUIs, as well as custom user scripts and the distributor.
PGS Express GUIs
- PGS Express Template:
- The system administrator or programmer creates a template that identifies a custom processing script, one or more data streams, and an output format.
- PGS Express:
- The user selects a template, selects a single data stream if the template contains multiple data streams, and defines an area of interest (optional) and distribution point(s) for a product.
Custom Processing Scripts
These are user-created processing scripts that are invoked to do the actual processing and product generation. These scripts must be written so that they accept the following command-line arguments in the order shown: stream, master, output file, input file(s), optional user arguments.
The PGS Distributor
The PGS distributor is a daemon that manages delivery of products. Delivery is independent of the time of product generation and doesn't interfere with product generation. The distributor has these features:
- Delivery of multiple products at a time to multiple recipients.
- Delivery by one of two means - FTP or copying (remote copy is not available for PGS Express) - with output file naming handled via a template.
- Delivery-attempt options.
- Options for post-delivery scrubbing of local directories.
TeraMaster is a GUI for viewing, creating, and modifying masters. A master, also known as an area of interest (AOI), is a TeraScan dataset that defines an area of the earth's surface in terms of map projection (shape), extents, and pixel resolution.
Masters are used in TeraScan for three purposes:
- 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.
- 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.
With TeraMaster, the user can define a master area for any part of the world, by using the computer mouse or by entering numbers into fields. The user can:
- Select map projection from a menu.
- Enter center latitude and longitude from the keyboard or select a master center point by clicking on a map.
- Specify master extents by entering area height and width from the keyboard or by selecting the area from a map by dragging a box around it.
- Specify pixel height and width.
- Zoom in and out on a map to increase or decrease area size, pixel size, and pixel density of the master.
- Map projection options for masters are: Albers conic, equal area cylindrical, equidistant azimuthal, Lambert azimuthal, Lambert conic, Mercator, Mollweide, orthographic, perspective, polarstereo, polyconic, rectangular, stereographic, UTM
TeraVision is the TeraScan GUI for displaying and manipulating TeraScan data images and overlays. TeraVision has these features and capabilities:
- Capability to present data as images.
- Capability to present data as contours, vectors, wind flags, marker plots, or stream plots that can be overlaid on images.
- Capability to add informational overlays such as topography contours, bathymetry contours, latitude/longitude grids, user annotation, weather fronts, and standard meteorological symbols.
- Animation of a series of images (time/product looping).
- Data analysis tools for generating and displaying histogram plots, profile plots, Skew-T diagrams, and scatter plots.
- Data measurement with tools for distance, bearing, area, perimeter, mean, median, minimum, maximum, and standard deviation.
- Easy access to products via real names like Pacific Sea Surface Temperature rather than pcfsst.img.
- Easy editing of data display parameters, which can then be saved as future viewing preferences.
- Image enhancement via color palettes, convolution filters, and histogram equalization.
- Manipulation of the view area by panning and zooming.
- Data combination through fading, compositing, mathematical functions, and true color imaging.
- Product or plot output to any color or black-and-white PostScript Level 2 printer.
XVu is the original TeraScan X windows GUI for displaying and manipulating data. It has capabilities similar to those of TeraVision, with the added capability to allow manual navigation of the data. This is especially useful for adjusting the satellite pitch, when necessary, for SeaWiFS passes.
The System Configuration Editor is a GUI that allows a person to easily enter into the system information that the TeraScan software needs access to in order to be able to control data reception. The information is organized into telemetry chains. A telemetry chain identifies a telemetry and the chain of hardware components used to receive the telemetry. A system may have more than one telemetry chain.
One part of the System Configuration Editor is for the purpose of defining the layout of the pass disk, the hard disk area specially formatted for the storage of raw pass data (online passes). The definition includes the number, size, and location on disk of the pass partitions, and the telemetries that can be stored in each. Each partition accommodates the data from one satellite pass. Note: For Linux and X-Band systems, the file $PASSDIR/BAST must be edited manually.
This information is stored in a TeraScan configuration file. Note: For Linux and X-Band systems, the file $PASSDIR/system.config must be edited manually.
Satellite TV enables the user to view direct-broadcast data as it is coming into the TeraScan system from the satellite. Satellite TV can also be used to view raw pass data already stored on disk.
TeraScan continually generates a log of data-capture events and a series of data-processing logs (one for each pass captured). The purpose of the Log Viewer is to provide the user with a means of easily viewing these log files. The information they contain can be very useful for diagnosing and troubleshooting problems with data capture and processing.
Trackeye is a window that can be displayed on the screen and used to monitor various aspects of antenna tracking and data-capture progress.
The Tracking Monitor GUI presents a continually updated status of antenna tracking and signal reception. The information it displays for each pass received is also stored in a file that can be replayed through the GUI for diagnostic purposes.
The Satellite Tracker allows multiples satellites to be tracked and displayed simultaneously, along with multiple receiver sites and the sun's location. Orbit plot updates are performed every thirty seconds. All satellites, receiver sites, and the sun are plotted on a base map of the earth in either an orthographic projection or a Mercator projection.
StatPass reports the status for the previous, current, and next scheduled pass by telemetry.
Last Update: $Date: 2002/09/10 20:30:00 $