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Ordering high-resolution satellite imagery can be a real hassle. It requires finding a reputable satellite imagery distributor, knowledge on what type of image data is needed for the job, running a search through several image search and discover services, obtaining a price quote, negotiating terms, sending a purchase order, waiting for the order to process, downloading very large data files, and finally ingesting the imagery into specialized mapping / GIS software. Who would have thought it could be so difficult to obtain critical information? 

Taking away the tedious task of ordering imagery pixels from the marketplace, there are now three very mature online subscription services available - allowing us to get on-demand access to high-resolution satellite imagery anywhere in the world at any time. Each service has its own unique character and advantages. All three services allow GIS/IT Managers to serve the imagery to the end user desktop through APIs (Application Program Interfaces) whether through a simple URL or a feature rich desktop GIS software plug-in. 

All are paid subscription services except for the “free” Google Earth. If you’re not a software geek or you don’t work in a GIS environment, then don’t worry, as each service has easy to operate user-friendly interfaces that work in any web browser. Below is a brief description of each service and highlighting its respective advantages and target user. 

Google Earth 

Who doesn’t know Google Maps and its big brother, Google Earth? Google Earth is a classic desktop application but now also has a web browser interface, which is not a replacement to the classic Google Earth but advances the goal of moving the application from a legacy desktop platform to the web. As we all know, Google is not an imaging satellite operator, though it did try to do be in the past when it owned the Terra Bella satellites, which are now owned and operated by Planet. However, we are including Google Earth in this in our article as it has become the benchmark for consumer mapping and is widely used by many businesses. 

Google mines data from the public domain, collects large volumes of aerial imagery, purchases commercial satellite imagery, creates its own map data content and location-based services, and links all this data successfully to its web search and advertising services. Google at its core is not a mapping business but they show how geographic data and a mapping platform is integral to its success as the world’s largest web search and advertising enterprise. 

There’s no need to describe all GE’s capabilities but the most powerful features are its massive data content of imagery, terrain, and vector GIS data, geocoding, navigation, and of course it’s slick 3D globe that operates on any desktop computer, smartphone or tablet. 

In our experience, despite its powerful capabilities, GE does have shortcomings. The data content is limited to whatever Google has available in its platform. A common complaint that we hear from our customers is that the imagery in GE is too old or does not have the image for a specific historic time window. GE does not provide spectral band data that is needed for the professional image analysts (ENVI users). Image metadata is lacking – there is no information on how the imagery was collected and often the image acquisition date is incorrect or cannot be found. Imagery is not always produced to the highest possible accuracy level. Users are unaware of an image’s specific accuracy. GE’s objective is to attract consumers to its search website and driving search-engine usage and advertising revenue. GE is focused on major metro regions and developed countries, so or rural areas of the world. GE does not allow data download, large format printing, distribution, or content can be lacking in remote data sharing. GE has little to no flexibility for displaying and publishing vector overlays, as they are tied to the platform. GE does not allow customization or user-requested image refresh. One other item to consider mentioning is that the Google Earth terms of service

() may not be conducive to some business needs. Finally, there is the issue of privacy and confidentiality where platforms like GE collect customer data for future monetization. These disadvantages are exactly the advantages of the following commercial satellite imagery subscription services! 

SecureWatch 

�Ѳ��油��’s SecureWatch subscription provides on-demand access to the some of the most recent, and highest resolution satellite imagery, mostly 0.5 m but also and WorldView-3 0.3 m spatial resolution, currently the best spatial resolution commercially available, as well as and other geospatial data including RadarSat SAR imagery. This platform provides flexible access options including online streaming and download, API, and integrations with ESRI ArcGIS. Maxar has the largest holdings high-resolution satellite imagery with 20 years of coverage, 2000 to present, with new images added daily and the added benefit of a customizable image alert service as images arrive into the platform. The satellite sensors include the first high-res. images from IKONOS and QuickBird to the latest collections from GeoEye and WorldView. Light image analysis such as visual change detection, map annotation, basic measuring capabilities are available within the platform. As with the other platforms, all imagery is provided as 3-band natural color orthorectified base map. However, one of the key benefits we have found of SecureWatch is the ability to download any imagery for offline analysis including the unique WorldView satellite’s 8-band multispectral and SWIR (short wave infrared) band imagery, global image mosaics, as well as in-track stereo imagery and SRTM-2 30 m DEM data where available. SecureWatch even has a plug-in for Google Earth and uses both Open Street Map and Google Maps data for geocoding. Once going through the series of tutorials on �Ѳ��油��’s web site, it seems that SecureWatch was specifically designed for defense and intelligence organizations, especially with the availability of standard NATO military annotations, but SecureWatch is just as useful for a host of other applications from utility operators, energy companies, and environmental managers. SecureWatch also allows tasking orders permitting the user to program a new image collection of any specific area of the world. 

Airbus OneAtlas 

Hot on the heels of �Ѳ��油��’s SecureWatch platform comes Airbus’ OneAtlas, a direct competitor, which our assessment shows has its own set of key advantages over other subscription platforms. Even though Airbus does not have as deep an archive of very high-resolution images than Maxar, it is adding as much daily data volume. The key imaging satellites included in OneAtlas are the two SPOT 6/7 1.5 m and Pleiades-1 0.5 m sensors. Later in 2020, Airbus will add TerraSAR-X SAR and Pleiades Neo 0.3 m optical sensors. Whereas SecureWatch has high-res. coverage globally, OneAtlas 0.5 m high-res. imagery are mostly concentrated in urban or densely populated areas of the world, while rural areas are mostly at 1.5 m resolution. OneAtlas has better quality terrain data as Airbus has global WorldDEM 12 m DEM coverage. Full image spectral band data download as well as tasking of either SPOT or Pleiades is available in OneAtlas. API integrations are of course available in OneAtlas and mobile access through tablets and smartphones – though I would not personally recommend using a small display for such a rich content platform. A key advantage of the OneAtlas platform is its analytical capabilities using its Analytics toolbox. A selection of analytics can be run on top of OneAtlas archive imagery including automated car and truck detection, ship and aircraft detection and a powerful infrastructure change detection tool. OneAtlas also has the ability to monitor multiple AOIs. It has its own slick looking reference base maps and excellent geocoding. We find that he main applications of OneAtlas are Business and Financial Intelligence, Defense and Security and Urban Planning. 

Planet Explorer 

Last, but not least, comes Planet Explorer which is another platform that will run in any web browser. Of course, Planet offers its own API integrations with direct integration to ArcGIS and the open source geospatial platform QGIS. We see Planet’s biggest advantage as the frequency of image collections with its signature huge constellation of PlanetScope satellites, also known as Doves, which collect the entire surface of the earth daily at 3 m / 4 m resolution with 4-band multispectral. They have a data archive going back to 2009 when the RapidEye constellation was launched. In common with the other platforms, Planet offers its own version of high-resolution imagery from its Sky Sat constellation which was 0.8 m resolution with 4 multispectral bands. Planet recently announced that it will be improving the spatial detail of its Sky Sat constellation by lowering their orbit and will soon be offering 0.5 m images to compete with Airbus and Maxar. We see one disadvantage of Sky Sat compared to Airbus and Maxar satellites are their small footprints and less accurate geometry. Explorer provides AOI-first programmatic search, download, and image alert notifications. It also has automated image processing functions such as orthorectification, radiometric corrections for sensor artifacts and transformation to at-sensor radiance, and top- and bottom-of-atmosphere corrections reduce spectral inconsistency across time and location. Like the other platforms, images can be compared against each other visually with side swipes or flickers. 

Summary 

Image subscriptions are the state of the art of visualizing and exploiting large volumes of satellite image data. It won’t be too long in the future when no one will be consuming imagery by purchasing individual, large, and cumbersome GeoTIFF image pixel files. Airbus, Maxar and Planet and other new players in the satellite imagery market won’t be standing still on development of their platforms and technology allowing all of us imagery nerds to benefit. 

Our experts are ready to help you find the best imagery or subscription plan for your projects. Contact us today at GeospatialData@L3Harris.com 

Commercial High-Resolution Satellite Image Subscription Services versus Google Earth