Kodak service spots changes in aerial pics

Eastman Kodak Co. earlier this month unveiled a new service to help federal agencies detect changes in aerial images of landscape that might not be readily visible to the human eye— a capability generally associated with Defense and intelligence agencies.

The new service, called Clear Change Imagery and available through Kodak's Commercial and Government Systems Division, is based on Kodak-proprietary "change detection" software and is available for film or digital imagery.

Currently, the service is available for black-and-white images, black-and-white infrared images and color infrared images. But John Boland, a Kodak program manager, said he expects the service to evolve to handle other types of imagery.

Under the service, customers will provide the company with historical aerial imagery— for example, of a forest as it appeared 20 years ago— and more recent imagery of the same site. Kodak will apply its change-detection software, using color to highlight changes in the landscape. The service might plug in colored dots for trees appearing in one image but not in another, for example. Kodak will provide the customer with a copy of the highlighted image in hard copy or digital format.

Observers of the imagery industry said the new service could be useful to agencies such as the Federal Emergency Management Agency, which might use the service to assess hurricane damage; the Environmental Protection Agency, which might use the service for monitoring wetlands; and the Interior Department, which could use Clear Change Imagery to manage federal lands.

Although change-detection software is usually rolled into programs for processing digital imagery, change-detection software for traditional aerial photographs is not common, according to one federal official.

"I'm not aware of good pattern-recognition software that would give us land-use/land-pattern change from photography," said Dave Wolf, the geospatial information manager for the Envirofacts Warehouse Team at the EPA. Envirofacts is a database of information of EPA programs and facilities.

"The Navy, the Air Force, the military, the spooks have always been doing this, but it's always been very pie-in-the-sky, very expensive, very exotic," said Pat Garvey, director of the Envirofacts Warehouse Team. He said such a service could help agencies avoid the confusion that emerges when several people use their eyes— not software— to determine changes in a set of images. The EPA currently does not use such software.

But the Kodak service may fall short of some federal users' needs. The service shows readers simply that something has changed. Fred Limp, director of the Center for Advanced Spatial Technologies at the University of Arkansas, said the service would be more valuable if it showed how something has changed— by reporting that a grove of trees has been replaced by a patch of cement, for example.

"The more information you can provide to the user in the nature of change makes it more useful," Limp said.