Graphical Methods for Interactive Science Data
 Analysis and Visualization


The long-term objective of our research is to develop and distribute freely available software that allows users to quickly and easily visualize and analyze data on the majority of the computer platforms in use today.


Our approach is to use emerging network technologies to develop a multi-disciplinary, multi-user, multi-platform visual data analysis system for rapid and interactive data exploration. In particular, we have chosen to use Java to create what is to date a stand-alone client tool called WebWinds. Our approach may also be characterized as a user-driven development activity which seeks to avoid building solutions in search of problems by addressing real and current scientific problems. For this reason, the task is carried out in very close collaboration with several scientific investigators and teams.


This fiscal year we have had 4 releases of our software. The main features of each release are listed below:

Version 0.407 Beta III Sept 29, 1998

  • Mainly a bug fix version:

PDS/VICAR files read incorrectly, some HDF files read incorrectly, file finder moved to wrong file tree, calculator application failed for some operations, Combine layout incorrect, nonfunctional help buttons removed, Color Tool had no effect.

  • Early release had an omission crucial for the Mac version to operate as a helper application
  • The documentation has been upgraded to fix errors and omissions.
  • Quick install versions created for Mac and PC
  • (Mac) MRJ early release software not recommended

 Version 0.505 Beta IV Dec 29, 1998

  • New and enhanced display and control tools: Contour, Grids
  • Preliminary (FITS, NetCDF) output capability
  • New data formats: ASCII table, HDF-EOS Swath (with geo-location)
  • New scripting capability which allows: automatic session setup or re-run, collaborative sessions over the internet
  • An integrated, context sensitive help system has been developed. Because it uses the documentation, the latter is no longer bundled separately but is included in the software download

 Version 0.573 Beta IV Jan 20, 1999

  • This is a bug fix release:
  • improperly constructed HDF and HDF-EOS files caused a null pointer exception .slang (script) files were not properly recognized via command line input

Version 1.00 released July 20, 1999

  • Data Objects may be saved in the following file formats: Binary (Raw) Flexible Image Transport System ("FITS"), Video Image Communication and Retrieval ("VICAR") and Network Common Data Format ("NetCDF")
  • Buttons, text pads and messages have been expanded, clarified and made consistent across applications
  • File concatenation: multiple files can be stacked together to produce a larger file for most file types
  • FITS files with coordinate and/or projection information can be displayed with that information. Thus, cross-hair, grids and other Overlays appear with the proper coordinates/projection
  • A new Overlay tool allows tabular ASCII data to be superimposed on an Image. These overlays can show variations in symbol size, color and range which can represent the numerical value of the tabular data
  • Grids and tic marks are compatible with non-linear scales
  • Shortcuts can be generated automatically with macros
  • A new Pause tool allows the temporary delay of the execution of a script, allowing, e.g., the selection of a file

One publication (Elson et. al, 2000) will result from this year's work.


We have developed the only freely available, ready to use software package with the following attributes:

  • Cross platform capability: Windows (95/98/NT), Mac, Unix/Linux.
  • The ability to present and manipulate 2 and 3 dimensional data in a variety of 1 and 2 dimensional display tools.
  • The ability to subset and subsample data on input or display output, making it possible to handle very large data sets.
  • Simultaneous display and analysis of multiple data sets which may be unrelated.Interactive data, image and color manipulation.
  • The ability to act as a Web browser helper application.
  • A scripting language which allows session configuration, re-run and real-time network collaboration, automatically.
  • A context sensitive help system.
  • Complete documentation including examples.
  • The ability to save modified or original data in several formats including FITS and NetCDF.
  • The ability to stack (concatenate) files together to produce a larger file.
  • An Overlay tool which allows tabular (ASCII) data to be superimposed on an Image.
  • Automatic shortcut (macro) generation.
  • A Pause tool that allows the temporary delay of the execution of a script.
  • Compatibility with Java 2 (JDK 1.2).
  • The ability to display several types of coordinate projections for appropriate FITS data.


The following new capabilities are planned for FY00:

  • Visual subsetting
  • Network distributed-object version of WebWinds
  • Animation record/playback tool
  • Tiling
  • Add subset capability to all data types
  • Efficient 3D rendering
  • Georeferencing/geolocation of point data
  • Point data overlay
  • ASCII output
  • User selectable point data interpolation
  • 'Snapshot' capability with output as .gif, .jpeg and Postscript
  • Bounding curves and circles

The following capabilities will be added farther in the future:

  • Roving agents
  • User accessible builder tools,
  • Interfaces to other visualization and database management packages


Click on either of the images below to see an example of how WebWinds operates.

over_sm.jpg image1_sm.jpg

Point of Contact

Lee Elson

Jet Propulsion Laboratory

(818) 354-4223


To Web Winds