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Imagery on the Big Screen

February 20, 2009 By: Cyrena Respini-Irwin


One month ago today, eager souls filled the National Mall, braving cold weather and enochlophobia to experience the presidential inauguration firsthand. But for everyone outside Washington, the place to be was in front of a television or computer screen. Even those responsible for safety and security during the event relied on monitors — in a big way.

To help prepare for the logistically demanding inauguration, the U.S. Department of the Interior's (DOI) Interior Operations Center in Washington, D.C., used an OptIPortal — a four- by eight-foot tiled display composed of flat-screen monitors. The portable system, on loan from the Sioux Falls U.S. Geological Survey (USGS) office, displayed 1-foot-resolution aerial imagery of the National Mall and surrounding areas on a 100-megapixel "wall" of 15 monitors.

Brian Davis explained that on a standard-sized monitor, users would be limited to viewing one building at a time at that level of resolution. Davis, an IT researcher with Stinger Ghaffarian Technologies, contractor to USGS, works in the Earth Resources Observation and Science Center at the Sioux Falls office. "The monitors [in an OptIPortal] are aggregated together as if it were one display," he explained, noting that the fully scalable technology can accommodate as many monitors as needed for a particular application.

Users can pan, zoom, and freely roam around the imagery using a keyboard, mouse, or wireless game controller. And they can do so without delays, thanks to the MagicCarpet software running on the Linux cluster that drives the display. Each node manages its own display space, said Davis, and that information is aggregated by a master node before being shown on screen. The viewing software refreshes the pixels composing the requested images at 30 times per second.

Technology Serving Science

The University of Illinois at Chicago's Electronic Visualization Laboratory (EVL), in collaboration with partner agencies and universities, developed the OptIPortal technology with funding from the National Science Foundation (NSF). Today there are 34 of the systems in use by scientific researchers around the world; for the past six years, USGS has worked with EVL on geologic projects using the portable, 15-monitor version of the display system.

The monitors that make up the viewing surface of any OptIPortal, and the computers that run the EVL-developed MagicCarpet software, are all standard off-the-shelf items, not custom hardware. "They're just component parts that you can mix and match," said Davis; that feature makes the technology useful to a broader range of users. NSF's goal, he continued, is to nurture technologies that will be useful in a wide variety of Earth science and information technology applications. With that in mind, EROS personnel like Davis act as liaisons, facilitating collaboration between universities and government agencies like USGS. "Technology researchers in universities don't want to operate in a vacuum," he said.

What researchers of all kinds do want is to convey information about their projects, sharing it with colleagues, managers, funding entities, the public, and the press. "What we're really trying to do is develop visual communication tools," said Davis, noting that the medium has a significant impact on how quickly and thoroughly the message is understood. He gave the example of a stereo-display model that showed fires on the Montana landscape in 3D. "To do that visually, instead of with charts and tables — within two minutes, the audience gets it."

The Future of the Portal

The OptIPortal has already proved itself as a research and communication tool, and it will become more valuable as the technology continues to evolve. As high-resolution televisions continue to increase in size and decrease in cost, they are becoming an attractive option, and may eventually replace the 21-inch computer monitors currently used in the DOI OptIPortal. Also, there's great potential for more and better software applications for the system, Davis reported. While MagicCarpet is a basic program, SAGE (scalable adaptive graphics environment) is a higher-level option already in use with high-speed, optically switched networks.


John R. Evans, USGS information technology specialist, briefs outgoing Interior Secretary Dirk Kempthorne (center) and Secretary-designee Ken Salazar (right). Image courtesy of John Evans.

Although the OptIPortal provided DOI staff with high-resolution images of the National Mall, separate displays and software were required to view road networks and other data, which couldn't be overlaid on the OptIPortal display. "This system is not a GIS," Davis noted. "We need to get to that level of complexity so it becomes more useful." Davis believes that with the recent turnover in leadership at DOI now complete, he and his fellow researchers will begin a variety of long-term projects to enhance the usefulness of the OptIPortal.

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