But what can we do with this data?
For some of us, it's no secret that all this data belongs to operators of spacecraft and is available to government organizations, commercial companies, and individuals collaborating with spacecraft operators. However, not all of us can or want to process this data ourselves. Most of us need derived products from this data.
But what kind of products?
The first thing that comes to mind is a map. Topographic, thematic (tourist map, population distribution map, and others). A map, as a product depicting terrain using conventional symbols with a certain accuracy, was invented long before Emé Lossed photographed Paris from the roof of a tall building and created a city plan from the photos, and the 16th-century Turkish admiral Piri Reis depicted a very detailed coastline of Antarctica, now hidden by kilometers of ice. But a map is a very old product and maps have their drawbacks. A map can be subjective — the person creating the map decides what to depict on it and what not to, and a map can be objective — in this case, everything depicted on the map is shown according to clearly established rules and instructions, but some information is lost that complements the spatial description of the terrain. On a satellite image, you can see more. Objects in satellite images are displayed with all their features and appearances. The completeness of information in the image is limited only by the scale of photography and perspective (the direction in which the photography was performed).
A satellite image of a large area of the Earth's surface is an immortalized moment of time and space in which the displayed Earth's surface looked exactly as it is. The shape, structure, color of building roofs are visible, and even walls. Clusters of people in certain areas of the terrain, hectares of growing plants, trees, machines processing agricultural land, traces of legal and illegal tree cutting can be seen. It turns out that a satellite image is not just raw material for creating a product like a map; it is also a very powerful tool for proving the existence of a phenomenon or process at a certain point in time, as we can observe a particular object or territory where interesting events unfold.
Decades of collecting such immortalized moments. Only the archive of DigitalGlobe, if all the areas covered by images are combined, will cover about 9 surfaces of the entire planet Earth. 9 surfaces covered with data with a spatial resolution of half a meter and better. And this is just one satellite imaging operator. There is the European AIRBAS with its satellites, there is Twenty First Century Aerospace Technology providing imagery from satellites like TripleSat, TH-1, ZY-3, GF-1, GF-2. There is UrtheCast with the DEIMOS 1 and 2 satellites and many others. The Belarusian spacecraft has accumulated a huge archive of satellite information over five years of orbiting, together with the Russian spacecraft Canopus-V. Imagine how much data this is!
With the appearance of satellite maps on the market from Google, Yandex, BingMap, and others, we realized that satellite images stitched together into unified mosaics of large sections of the Earth's surface are a very useful product that can be used as an addition to an existing map or as a ready-made material. Unfortunately, satellite data on such maps are updated with a specified regularity and localization only by their owners, and the accuracy of the data on such satellite maps is objectively not established, therefore they are not applicable for producing any precise engineering surveys or other works where the accuracy of placing a particular object is extremely important. Updates also occur without notifying the product consumer about the update area, and some areas remain provided with outdated information for years. Therefore, there is a need for accurate global and regional satellite maps with a defined update period. Primarily for those for whom the accuracy of terrain contour representation and update regularity is important.
Seamless, color-matched, tone-matched mosaics. We named our product "ORTOCART". Using the archives of various satellite operators, the company "Innoter" creates mosaic images of extensive areas with the accuracy necessary and sufficient for the Customer of such mosaic images.
How does it work?
We check the archives of available data operators for materials that are suitable in parameters for the Customer, both domestic and foreign spacecraft, form preliminary mosaic pictures, obtain materials, align the materials with each other using existing or provided by the Customer plan-altitude data of the area of interest, perform transformation of space imagery materials, correcting the position of image pixels relative to the relief of the terrain and the geometric model of the images themselves (the process is called orthotransformation), obtain orthotransformed images of processed space imagery. These images become the basis for creating the "Ortocart" product.
We cut out areas of the terrain from the images that are free from clouds, snow (if necessary), or other factors that do not meet the Customer's requirements. The cut-out fragments are stitched together into a single picture. And since the images were aligned before orthotransformation, the contours of objects at the image borders do not diverge with sufficient accuracy for the Customer. Then images with different spectral histograms are aligned with each other, and seams at the borders between images are smoothed, making the border between images indistinguishable or practically indistinguishable. As a result, we obtain a seamless, color-balanced, contrast-enhanced orthotransformed mosaic with the accuracy of contour image determination established — "Ortocart". Local updates are also available. The Customer can set the periodicity and order of updating such a seamless mosaic. Thanks to many years of work with satellite operators, we can designate areas for new imaging to update "Ortocart" data, and thanks to the capabilities of modern photogrammetric software, aligning and stitching new images is done without difficulty. "Ortocart" can be used when it is necessary to obtain a unified cartographic base over extensive territories and for the purpose of creating various geospatial information: determining the population density of territories, identifying indirect evidence of the existence of areas prone to hazardous natural phenomena (such as landslides), creating and updating topographic maps, determining the position of coastal lines of extensive hydrological objects, boundaries of objects within the framework of deciphering monitoring, and qualitative-quantitative characteristics in forestry activities, as well as territory planning.
I'll add that the production work to create the "Ortocart" product is fully implemented using modern Russian software, which is taught at the famous university MIIGAiK, preparing specialists for work in the field of remote sensing.
The global or regional nature, as well as the accuracy and detail of the "Ortocart" product, depend on what the Customer wishes to receive. You can set the parameters and conditions for the seamless mosaic that you need for your purposes.
"Ortocart" — your own satellite map with the most accurate and detailed images. It's waiting for you!