CycloMedia: Geo-Referenced Measurable Street-Level Imagery

Over the past decade, there have been numerous efforts to capture and deliver street-level imagery of major urban areas. The big players, Google Street View and Bing Map Streetside, are well accepted, and most of us use them regularly to get around. But as both indicate in their user agreements, they are for entertainment and marketing and not intended for critical applications. Other than geo-referencing the camera location, there is no metadata and no measurement capability.

More serious users such as tax assessors, transportation planners and emergency responders look to companies like iLookAbout, Facet, Tyler Technologies (formerly Yotta MVS), Geospan and others for imagery that is geo-referenced, measurable with good metadata. IMTS has even been used in overseas combat areas to gather baseline data for intelligence and tactical planning. Its accurately positioned imagery has been used to fill in detail and occluded areas of 3D models derived from aerial imagery.

Although most of the above systems produce excellent geo-referenced imagery, the imagery is not geo-referenced to the pixel, and measurements are generally derived from linked ortho, oblique or LiDAR data. The exceptions are earthmine of Berkley California and a Dutch firm called CycloMedia, which has been in the imagery business for more than 30 years. Both have similar technology, but CycloMedia seems to have significantly more coverage and a more refined toolset.

The patented CycloMedia system uses a process that captures overlapping ground-level 360° panoramic images, called Cycloramas, at 5-meter intervals. The company initially tried merging its imagery with LiDAR data to derive point locations, but that method proved cumbersome and not very accurate, so CycloMedia developed a system that used only its images. Using its system of stereo pair analysis, CycloMedia is able to derive 3D location information with accuracies of 10 cm. The automated system is fast enough to collect those 5-meter interval images at speeds up to 70 mph.

The car-mounted system simultaneously collects accurate location information for the camera system using IMUs, RTK GPS, temperature sensors and precise ground-tracking odometers. The detailed location information combined with imagery from high-resolution cameras then forms the basis of an accurate three-axis location and measurement system. Although this is a very sophisticated system, no special vehicle modifications are needed, and the entire equipment package can be installed and removed when not in use. The system can even be installed on boats and compensates for the boat’s motion.

Once captured, CycloMedia then uses its GlobeSpotter viewing software to accurately locate and measure features in the imagery. The system uses two or more Cycloramas to determine the location of any point in 3D space using geometry between different views and achieving 10-cm accuracy. Earlier versions of GlobeSpotter required the user to identify corresponding spots on two or more Cycloramas to accomplish the point location calculations. That process has now been streamlined with the single spot “Smart Click” selection tool and process. When a user clicks on an object or spot in a Cyclorama, algorithms identify the same spot in adjacent Cycloramas. This facilitates the geometric calculation of the spot in 3D space. The software can then calculate distance measurements in 3D space between the accurately located points.

There is a very good video that shows the process better than I can explain it in this short article. The video shows how the images are organized and accessed in an ArcGIS Desktop integration including measurements, GIS data overlay and polygon creation from the imagery. The creation of these precision 3D environments then opens the door to other capabilities such as 3D model creation and the ability to accurately overlay GIS vector data. Note this example of the Cyclorama footprint locations with planimetric data overlaid on this road and overpass. The same system accuracy also facilitates very accurate edge matching of imagery as a user moves along a road.

CycloMedia and GlobeSpotter are designed to operate as a web service with all imagery stored in the cloud, but the system can also be run as a thick client with the imagery stored on local media. GlobeSpotter integrates Cycloramas, aerial imagery, GIS vector data and documents. It performs the calculations and builds the visualizations. Currently, all leading GIS software suppliers including Esri have built interfaces that allow for the integration of CycloMedia’s GlobeSpotter software with their solutions.

Note this screenshot of an ArcGIS Online session showing the Navy Memorial on Pennsylvania Avenue. You can view the same site and try navigating it yourself. Search for Washington, DC, and zoom in far enough to see and click on the silver balls linking to CycloMedia images.

Uses

The very robust and accurate thre-axis measurement capabilities of CycloMedia make it a natural for tax appraisers as well as a tool for city planning work. Features such as street lighting, road markings, bus stops, benches and other infrastructure are easily viewed, measured and inventoried. The extensive metadata, including location and date of capture, will help anyone needing accurate historic data or images for forensic work.

An especially strong capability of CycloMedia is signage inspection and inventory. When I was with the Atlanta Regional Commission, we spent considerable time and effort working with the Georgia Tech Research Institute to develop an automated video street sign identification and inventory system. The ability of CycloMedia to display each sign with high-resolution imagery, facilitate accurate measurements, and easily geo-locate and link each sign to a GIS database makes the system a powerful tool for transportation managers. The same capabilities could prove invaluable for firefighter pre-plans as well as police tactical planning.

Additionally, extensive work is underway to use the data rich imagery provided by CycloMedia to create photo-realistic and photo-accurate 3D models that could be interactively navigated. See more here.

CycloMedia seems to be a significant improvement in street-level imagery capture. The accurate geo-referencing combined with strong metric tools and the ability to build 3D models could prove especially valuable for military applications as well as disaster response and recovery. My thoughts jump back to Katrina recovery efforts. CycloMedia could have inventoried affected areas by car or boat. The resultant imagery could have been annotated and exported as a GIS layer. It would be interesting to measure the cost vs. benefits of CycloMedia compared to other technology and delivery platforms.