|This article does not cite any sources. (November 2007)|
Imagery analysis is the extraction of useful information from bi-dimensional graphic formats, including screen shots. This includes color and black-and-white photographs, infra-red photographs and video, radar screens and synthetic aperture radar formats, ultrasound, EKG, EEG, MRI, echo cardiograms, seismographs and others. In short, any type of sensor-related data projected in 2- and 3-D formats qualifies as imagery.
Prior to the invention of early photography, military commanders depended on scouts that would survey or recon enemy activity, depending on simple eyesight and human memory. Once photography became available, tactical information became frozen in time, details could be preserved, enhancing the quality of available information.
World War I saw the start of ground-based and aerial photographic collection. For the first time commanders were able to access timely and accurate intelligence. Such was the value of this type of information that observers in tethered balloons and scout planes were attacked, first with crude weapons and later escalating to machine guns and the development of the fighter aircraft.
Frank Luke, an American pilot procured incendiary ammunition and used it to destroy numerous enemy observation balloons, gaining the title of Balloon Buster. The end of the war resulted in the scaling down of tactical and strategic capabilities, resulting in an almost dormant state in the development of photographic analysis. The perceived threat from Germany and Japan revived the collection and analytical capabilities of the major powers and helped military planners including U.S. General Dwight D. Eisenhower prepare for the next war.
In the 1930s experiments with film media and its processing resulted in the introduction of film that could now detect non-visible wavelengths in the infra-red spectrum. One of the first applications was the use by those associated with rare art collections. Previously invisible details made it possible to detect and deter forgeries.
Radar made its appearance during World War II, primarily in its early warning capability. In the early days of the Cold War, Soviet troops would use a directional radar beacon to lure surveillance aircraft toward their airspace in order to shoot them down. By this time radar scopes became available in larger aircraft monitoring Soviet-controlled border areas. Having these scopes made early radar navigation possible, indeed, in photos released by the Soviet air force, pictures were taken of the screens, documenting this use.
The importance of tactical information is shown in the case of Operation Market-Garden, the aerial invasion of the Netherlands on Sep 17, 1944. Photo missions revealed the presence of two Panzer Divisions in the city of Arnhem, a bridgehead at the farthest reach of those airborne troops assigned.
British intelligence Major Brian Urquhart warned his commander of the threat, but an overpowering optimism cause by the recent collapse of the Western front overruled any possibility of an objective threat assessment, resulting in a night-time river crossing in which out of 10,000 members of the British 1st Airborne Division that jumped into Arnhem, only 2,600 survivors would reach the southern shore 9 days later. In spite of the introduction of color film, photo interpreters to this day continue to use black and white because of the greater detail available. The early Cold War era also saw the introduction of strategic collection. In tactical collection, analysts count guns; strategic collection includes butter. The categories of collection is, of course, classified.
The post-Vietnam era saw the introduction of airborne infra-red sensors. Differences in temperatures between objects and their surroundings made it possible to detect targets on the ground. These early systems would record data which would be accessed once the aerial platform would land. Later developments in transmission technology would provide periodic data dumps and would further evolve into real-time collection.
Synthetic aperture radar would soon be developed in the later part of the Cold War. The concept of an optical camera aperture affecting the image acquisition process would be emulated with radar waves, providing an undisclosed amount of detail. One clue would be the NASA photo released in the late 1980s showing a previously hidden African dry riverbed.
This is also about the time when ultrasound would make its appearance. For the first time it was possible to view variations in tissue density which made it possible to detect possible tissue and organ anomalies. Another application was that of detecting material flaws in manufacturing.
Experimentation with monochromatic imagery (black and white) revealed the potential of exploiting the hundreds of shades of grey available in this medium. The next step would be to digitally manipulate the greyscale to enhance the acquisition of usable information. The first applications of this new technology would be by the intelligence community and by medical researchers who would refine and further develop the technology, resulting in the introduction of the CAT Scan.
Another technology introduced roughly at this time would be that of the echo-cardiogram, which could show heart movements and the actual blood-flow through its chambers.
One of the more recent developments has been that of magnetic resonance imaging (MRI), where tissue and blood-flow anomalies could be detected. Evidence of spinal cord injuries and even complex neurochemical reactions in the brain could now be detected and documented. Scientists have also explored the possibilities of multi-spectral imaging such as the 1970s LandSat, and yet more parts of the electromagnetic spectrum such as astronomical gamma-ray imaging.
The first use of tactical imagery obtained during the first World War readily revealed the straight man-made lines of roads, cites, airfields and trenches. Finding concealed high-value targets like artillery, ammo dumps, and other logistical sites was quite another matter.
This was a process that was strictly by trial and error, with the resulting body of knowledge transmitted to new recruits and officers. Terrain and the proximity to supported units would dictate probable locations of logistical routes, ammo dumps, supply depots and assembly areas. Being that the military by definition embraces uniformity, patterns of emplacement and concealment, once discovered would result in widespread targeting by artillery and air strikes. The size, shape, and surroundings of items frequently gave away the location of military assets, with shadows only making it that much easier to identify targets. The development of analytical techniques is really a part of the evaluation of the new technology itself. The first photograph to be taken was that of a French neighborhood. It was crude, yet it clearly showed the outline of the houses. Immediately it was apparent how the new technology, the chemical film plate, was of immediate usefulness.
In the case of infra-red photography, the new details made available were puzzling at first, and took some time to explain. In the pictures taken of works of art, the strange images would eventually be interpreted as showing a feature being painted over and finished. Simultaneous aerial coverage by photo and IR of a given target would reveal how a warm vehicle would warm up the ground and once moved, the warmed plot would stay warm for some time, giving the illusion of more vehicles. Just as in the case of an experienced scientist, once a new observation is made, it must then be explained.
In the case of the application of radar, all there was at the beginning was a variation of the cathode ray tube which would show only the distance to a single target. Only with the introduction of the more familiar round-screen format would radar reach its full potential. So, there were the raw data, but without the use of a readable 2- or 3-D format no-one can make that much use of this information. One thing to remember about radar is that when it comes to illuminating aircraft, most of the energy is deflected. Only the existence of corners, air intakes and flat surfaces that face the radar makes it possible to detect these aircraft. What is actually seen by traffic controllers is the return beep from the aircraft's IFF. As in the case of 9/11, once the hijacked aircraft's IFF was turned off, there wasn't much to see. This can also be seen in the use of radar reflectors that are routinely added to power lines in order to avoid crashes by low-flying aircraft. The actual characteristics of synthetic aperture radar is of course, classified, so one can only speculate on what is actually observable.
For the development of CAT scans, computer-aided design (CAD) had to come first. Pictures were publicized in the 1960s showing design engineers using light pen peripherals to draw proposed design features to be evaluated for fit and aerodynamics before costly manufacturing jigs had to be built. In the case of CAT scans, the information from x-rays is useless without 3-D capability.
For the development of ultrasound, the use of anatomical studies, dissections, and autopsies would have been necessary to provide insight and confirmation of what was now visible. It would have taken some time to establish average dimensions for organs and, in the case of pre-natal scans, body dimensions and growth rates.
The development of MRI would have been a question of comparing their data with that of CAT scans and ultrasound. As far as how they established the visibility of neurochemical reactions, that would have been dependent on current knowledge of neurological and physiological processes. Now a situation exists where a new technology that is based on previous understanding actually increases those fields of knowledge that made it possible.
The current emphasis of multi-spectral imaging is really a question of maximizing the amount of data available for geological, agricultural, and environmental research. This means that a given area would only have to be covered once, making global coverage a more economical proposition.
The latest imaging technologies are driven by nuclear physics and astronomic research. This can be seen in the evaluation of particle acceleration, where theoretical physics helps to make sense of the collected data. As in the case of particle physics, multi-spectral orbital imaging is driven by theoretical research, only to be confirmed by other sources.
Besides the traditional tactical and strategic use by civilian and military intelligence, other entities have made extensive use of this discipline. Law enforcement has made use of imagery in forensic crime scene documentation in order to determine how crimes were committed to include how the assailant approached and left the crime scene. Also, bullet trajectories can be detected in order to determine the location of a sharpshooter.
The United States Border Patrol have the use of imaging technology, determining transit routes and the detection of illegal aliens trying to escape into the interior, beyond the reach of the agents. Their only real problem is that there are far too many routes to cover with the manning and technology only able to do so much.
Highway departments make use of stereo and terrain analysis techniques to determine potential highway routes. As in the case of currently available programs, imagery is included with other types of information to create detailed maps useful for commerce, taxation, city planning, and infrastructure.
The most important application has been for medical and research purposes. Many advances in diagnostics and monitoring have contributed to the ever-increasing body of knowledge and treatment options. The only problem is that with the increase in diagnostic capability, the aspect of accountability and malpractice has made necessary the costly regimen of multiple-discipline testing. This is not about to change. The positive side of developing new imaging technologies is that enhanced observation and understanding will result in better diagnostics and treatments.
The introduction of LandSat in the mid '70s made possible new applications in the fields of agriculture, geology, mining, and the environment. The actual resolution would not be great, but sufficient for these types of applications. The raw data would include the grey scale, and information from a variety of sensors. The designers would find it necessary to assign colors for each type of return, creating a multicolored map.
Meteorological imagery since the '60s has made it possible to detect and monitor severe weather well in advance of its arrival, saving numerous lives.
One promising application would be in the field of archaeology. Terrain analysis would show trade routes, lines of communication, cities, forts, farming, grazing, water sources, supporting communities that surround cities and service trade routes, ancient borders, and more.
In the case of Ancient Egypt, IR would reveal water sources that would have supported communities in the desert. Terrain analysis reveals that in order to access the Sinai copper mines, one had to access the shallow eastward valley north of present-day Cairo and reach the Red Sea just south of Port Said. From there it would have been a question of sailing east toward the western coast of the Sinai and turn southward toward Ras Abu Rudeis, a small coastal plain just east of the two copper mines. The reason for this is that an overland route would have required the costly logistical support of garrisons through territory held by hostile desert tribes.
In the case of the biblical Exodus, terrain analysis excludes the traditional sites as being too far and not being accessible to such a large group of people. Advancing through mountainous terrain would have exposed them to ambushes. The only confirmed location within Egypt or the Sinai is that of Baal Zephon. Ancient papyri describe this location as being close to Ramses, Tahpanhes and present-day Lake Menzaleh.
Being that Biblical Archaeology is almost devoid of independent confirmation, one has to use what little confirmed information is available. Following terrain, they would have set out eastward along the Mediterranean coast, reaching the Wadi of Egypt (Al-Arish), and turning southward, following the wadi towards the interior. There are numerous dams crossing the wadi, easily seen from above. Travel would have depended on the use of scouts who would survey water sources, grazing areas and topography that would permit travel for such a large group of people.
Imagery would also benefit exploration in greater Palestine. Radar would readily detect tells (mounds indicative of multiple layers of ruins) in the plains. In mountainous terrain, it would be a question of branching out from confirmed locations and establishing a 10-mile radius, the idea being that cities depend on smaller, surrounding communities. Terrain would dictate probable trade routes, water sources, grazing, farming, and supporting infrastructure.
Surveying jungles would require terrain analysis and radar to detect stone cities and temple complexes.