The last decade has seen significant change in the world of spatial information. Over the past five years, remote sensing and photogrammetry have been especially subject to a revolution in imagery.
New sensor technologies have been created, processing and analysis techniques have been improved, and a broader array of applications has been developed. These have changed the industry forever.
The market for imagery created using traditional aerial film matured during the 1970s. The technological changes that have happened since have been limited. A few small growth spurts occurred as digital technology evolved; for example, when analytical machines, airborne GPS and photo scanning were introduced, and softcopy photogrammetry was adopted. However, these developments have not dramatically led to changes in either production processes or the products delivered to users.
Film imagery reached a terminal-maintenance phase in the late 1980s, and no significant investment in R&D has been made since. Today, only two vendors are servicing the global market.
Many purists, including NIIRS10 Inc. president Lewis Graham, believe that no new film aerial cameras will be available after 2006.
What, then, is next?
When recent investment in aerial surveying technology is analysed, one can see a shift from film to digital sensors. The process began during film's terminal maintenance phase. It is continuing now because new sensors, such as airborne laser scanners, are emerging. Moreover, private and public mapping organisations have been adopting digital camera systems and multi-sensor imaging operations.
Investment in these technologies is resulting in development of more-accurate imagery products and significant improvements in image quality. Because data is being captured directly in digital format, product generation times are being shortened. Users are enjoying the cost savings.
Digital sensors have now reached their growth phase. Systems are being deployed in Japan, the US and Europe. Locally, only the Australian Defence Force is operating a digital sensor, but it is widely anticipated that private organisations will commit over the coming 12 months.
In parallel with all these developments, the use of high-resolution satellite imagery has been growing dramatically. During that time, three satellites - DigitalGlobe's Quickbird, Space Imaging's Ikonos and OrbImage's OrbView - have been put into production. As a result, accessibility to imagery has been brought to unprecedented levels.
Access to daily coverage at sub-metre resolution around the globe is now a reality. The local market has expanded by almost 20 per cent. Over the coming years, that will increase.
New methods of doing business have been found, and have led to higher value datasets, flexible capture programs and access to GIS-ready data within 48 hours of capture. This has given satellite imagery significant cost advantages over its aerial imagery equivalents.
Also, satellite vendors are stimulating the market by providing flexible licensing options, such as whole-of-government licensing arrangements. They are also delivering higher-value products by further processing the data. New imagery customers are entering the market.
Over the coming years, imagery will continue to experience dramatic growth in its use, and in the number of applications and customers. A new generation of sensors will arise. Digital cameras will arrive in the Australian market. The number of high-resolution satellites that supply data to the commercial sector will triple.
It is delivering more accurate imagery products ...
This increase in satellite platforms will lead to a doubling in the daily coverage of every location around the globe. Satellites such as DigitalGlobe's WorldView will yield 45 centimetre resolution. Improved multispectral imagery will contain up to eight spectral bands. This extension of multi-spectral bands will lead to an increase in the number of applications and products available.
The technologies used in airborne sensors are essentially a clone of the ones used in high-resolution satellites. The next generation of aerial sensors will capture panchromatic and multi-spectral imagery concurrently, as do satellites today. Vendors will use these merged datasets to produce natural colour imagery that is equivalent to present day film products.
As time goes by, we may expect a host of more subtle changes. For instance, remote sensing and photogrammetry will merge.
Mapping organisations will face a challenge. They will have to acquire new skills and manage changing skill requirements in a rapidly evolving industry.
Aerial imagery will move into the realm of higher value data. This was previously the domain of high-resolution satellite imagery.
Imagery's traditional user base is broadening as a result of digital imagery. Organisations that have little or no experience of imagery are applying digital imagery techniques in industries such as multimedia or news agencies, and precision agriculture. Real estate and insurance have interest in new applications that have been developed in urban planning. Data fusion is now being developed for simulation and fly-throughs.
These organisations are not interested in the science behind the technology. They require reliable solutions that meet their organisational requirements. When these solutions are delivered - through integrating imagery and related geospatial data in decision support systems - it will create significant avenues of continued growth throughout the spatial industry.
We are entering a world of on-demand, high-resolution, cost effective digital imagery that can be accessed in a turnaround time of only several days. We can expect faster coverage of given areas, regular repeat coverage, multi-user licensing and use of more powerful datasets. The range of possible applications will expand as a result.
Imagery will especially be an integral part of decision-support systems. Raster imagery will become more integrated with vector GIS. ESRI's image-analysis extension is a pointer to the future.
The significant benefits that will be created as a result of these new digital sensors will give mapping scientists and spatial professionals opportunities to contribute to improving the community, the environment and the economy.
For the future, the only limiting factor is our imagination.
Andrew McCleave is a partner at Sinclair Knight Merz and the manager of that company's DigitalGlobe business.
