In addition to becoming an invaluable tool for law enforcement, VISAR was named NASA's 2002 Commercial Invention of the Year (see NASA Tech Briefs, June 2003, page 22). NASA Tech Briefs: What is VISAR? Dr. David Hathaway: VISAR is a technique for stabilizing video that goes two steps beyond normal image stabilization. It takes out motion -- horizontal and vertical -- like other methods do, but it also takes out changes in rotation if the image is rocking back and forth from someone walking with a camera. It also takes out changes in zoom, either from a cameraman moving closer or away from an object or actually zooming in and out unintentionally. NTB: How did VISAR originate? Dr.
Hathaway: It was developed when law enforcement came to us asking
for help with videos they had of crime scenes where they needed a cleaner
image. We realized that the way to do that was to have the ability to
add images together. These were dark, nighttime images and if you add
them together, you can get a cleaner image that can be sharpened easier.
In order to add them together, you have to register them, which means
that they have to match up as to where things in the image are. So we
had to develop a process that would do the matching as well as stabilize
the video and keep the image that you are looking at steady in your field
of view. NTB: How is VISAR different from other video stabilization techniques? Dr. Hathaway: It provides an image that is relatively free of noise and random fluctuations in brightness; if you tried to sharpen it up [using non-VISAR software] the image would be ruined. VISAR reproduces clean images that you can sharpen with techniques that wouldn't be available otherwise. NTB: How are law enforcement officials using VISAR today? Meyer: We occasionally still get requests for assistance. Our licensee,
Intergraph Government Solutions, also gets requests and is selling workstations
for law enforcement and military applications as well. Occasionally,
we do work on other cases and get involved, although it is heart-wrenching
to sometimes have to turn down requests. NTB: How else is VISAR being used? Meyer: I've been doing some work with ultrasounds. The difficulty with fetal ultrasounds is the way the doctors move the wands around so rapidly, and irregularly. If you've seen typical ultrasound video pictures you know they are inherently noisy. At one point the doctors were able to hold the wand pretty steady and move it across the abdomen, and were able to take half a second to a third of a second of video. From that we were able to make a slightly crisper and sharper picture. I'm hopeful that one day if a more automated procedure was performed and the doctors could work the wands a little bit differently, this would result in getting sharper, crisper pictures from ultrasounds. NTB: Has VISAR been developed for the home user? Meyer: Our technology transfer department is still attempting to find
a licensee to get it to the public. We are very hopeful that one of these
software companies will step up to the plate someday and write a module
or tool and build it into applications such as Adobe Premier. NTB: What are you currently working on for NASA, and does it involve VISAR? Dr.
Hathaway: I spend most of my time doing solar physics and occasionally
get back to doing bits and pieces of VISAR-related things. There have
been a number of times where it's come in handy within my research. There
are other areas in which it has been useful, such as the series of images
that came from the International Space Station that astronaut Don Petit
took of moon rises and moon sets. To make them easier to look at and
nicer to see on the Web, we stabilized those using VISAR. Resources:
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2003
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