Basic Imagery Analysis
Imagery analysis is the art of analyzing images to extract useful information. Overhead imagery analysis has been practiced since 1858, when the first aerial image (of Paris) was taken by Gaspar Felix Tournachon from a balloon. Images were later captured from cameras carried by pigeons (1903), kites (1906), and compressed air rockets (1906).Wilbur Wright took the first photograph from an airplane in 1909 of Centrocelli, Italy. The intelligence value of overhead imagery did not go unnoticed by the military. Overhead images were collected during the U.S. Civil War,World War I, and World War II, but this increased in significance with the advent of satellite imagery. Corona was the United States' first photo reconnaissance system. It operated from August 1960 to May 1972 and was declassified in February 1995. During the 12-year program, it flew more than 100 missions and captured more than 800,000 images.25 The satellites in the Corona program were given the KH (KeyHole) designator from KH-1 to KH-6, with a maximum ground resolution (that is, for the smallest discernible object) of 6 feet.26.
Today Google Earth and Google Maps users enjoy significantly greater resolution with images collected using satellites and aircraft, opening up the art of imagery analysis to anyone with access to the Internet. These images, along with other information freely available on the World Wide Web, have magnified the sensitivity of the content of these online services. In the past, nations risked the lives of spies and service members to acquire what you now can simply download from your living room or office. Full coverage of the risk associated with overhead imagery is beyond the scope of this book; however, it is important to realize that although an untrained eye can detect sensitive information, an experienced imagery analyst can extract significantly more insight. Let's consider a few simple examples.
The first example is that of a humble parking lot. Google Maps has plentiful imagery of many cities with resolution capable of detecting relatively small objects, such as automobiles. Figure 9 shows an example of a shopping mall from Google Maps. Note that something as innocuous as a parking lot can reveal a great deal of information, such asvthe number of employees a company might have or whether the image was taken on a weekend or weekday.
If you've ever played a city building game, such as SimCity, you've carefully built a city by adding commercial, industrial, and residential zones, as well as transportation and public utilities. Similarly, you can analyze a city by deconstructing it layer by layer. See Table 1, which I've based on the menus of SimCity and other sources, for more detailed examples. A profound security risk arises from skilled analysis, and we can do little to protect against it, unless we want to install camouflage netting over our homes and businesses.
We face two major threats regarding online mapping and imagery: the sensitive information we disclose through our interactions with these services and the content itself. Our interactions reveal locations of interest and the time we were interested in them.We might reveal travel plans, confidential facilities, our homes, or other sensitive locations. Direction-providing services indicate specific destinations as well as the probable routes you will take. Social networks emerge as we share these locations via hyperlinks with our friends, families, coworkers, and readers of our blogs. Even apparently unrelated people can be linked because they examine or seek directions to similar locations. Table 2 summarizes the actions you might take when using mapping and imagery services and the types of information you can disclose.
The content itself also raises important security concerns. Your home, car, place of employment, perhaps even you, all probably exist in the terabytes of imagery data comprising Google Earth, Google Maps, StreetView, and similar services. In the future, we can safely assume that the number of sensors gathering information will increase.
Beyond static images, we will see video, perhaps combined with data from terrestrial sound sensors.We see early approaches now. The California-based company Wild Sanctuary has more than 3,500 hours of "soundscapes" and software that can layer relevant recorded sounds in Google Earth. AstroVision recently announced its plans to delive the "first live, continuous, true color image stream of Earth from space." We see only relatively sanitized data in publicly available systems. However, although it is likely occurring today, in the future it is easy to imagine multinational corporations sponsoring corporate overflights of locations of importance. Today we see powerful collaborative analysis of imagery through sites such as Google Sightseeing and Wikimapia, but in the future we can expect to see powerful automated processing augment these human-centric approaches. Advances in facial recognition, machine vision, data mining, and even automated lip-reading could one day be applied to global scale sensor data. Of more concern is that a future advance could be applied to all historical data. Even though a data-mining system cannot currently identify every face in Google's StreetView, a future system might well have this capability.
At their heart, mapping, directions, and imagery sites are about combining sensor data with other semantic information, such as highway traffic data, into a seamless, easy-to-use tool. I would like to suggest simple-to-implement countermeasures to help protect your privacy from surveillance sensors. Unfortunately, this genie is out of the bottle; unless we see major changes in privacy legislation, we need to seek new approaches to privacy and learn how to live in this environment. Currently, nation-states can use such extreme measures as anti-satellite missiles and armies can use battlefield deception and camouflage in an attempt to limit successful surveillance. Both of these are unrealistic to us average citizens. As one friend aptly put it, "I don't want to live in a place where I need to wear a ski mask to my local mall to protect my privacy."