What Is An Orthomosaic?
Orthomosaic Maps & Orthophotos Explained
Drones are state of the art meausring tools for helping to create orthomosaics.
But what is an orthomosaic? How are they being used? And why would you want one?
Put simple terms, an orthomosaic is similar to Google Earth, but much more accurate.
Imagine a large, map-type image with high detail and resolution produced by stitching many geo-referenced smaller images & captures together called orthophotos.
An orthophoto, sometimes referred to as an orthophotograph or an orthoimage, is an aerial photo that has had the lens distortion corrected, camera angle, perspective, and topographic relief, which are changes in the elevation of the earth’s surface at certain points. These corrected orthophotos haven't any distortion whatsoever and a consistent scale across the image, this is very usable.
What’s the Difference Between a Normal Photo and an Orthophoto?
The key difference between a traditional aerial photo and an orthophoto is that the perspective and accuracy.
A normal aerial photo, as you'll see below, features a perspective view. You can see the edges of buildings and other objects, and therefore the perspective changes counting on where the photo was taken.
An orthophoto, is what is called “orthorectified”.
It is geometrically corrected for this attitude view, along side lens distortion and point of view , to make a wonderfully straight-down view of all objects within the frame as you would see on Google Earth.
The precision and accuracy of orthophotos means both orthophotos & orthomosaics have an equivalent quality as high definition maps and therefor you are able to measure true distances.
How Are Orthomosaics Being Used and Why Would You Want One?
One of the main use cases for an orthomosaic is to get an updated view of a large area of land. Google Earth is helpful, but often the imagery is outdated & not as resolute.
Your new housing development project could be near completion, new construction projects could be underway, or the landscape could have changed from natural disasters or indeed development.
Real estate companies may also want an updated view of property to ascertain if it's right for the project in hand.
Whatever the reason is, orthomosaics are the simplest thanks to combine aerial images for an updated view of your land.
Use Orthomosaics for Accurate Measurements
Construction firms also find orthomosaics particularly useful. They can get updated views of their construction sites on a daily basis, and that they can leverage the accuracy of the orthomosaics for precise measurements. Software programs like Drone Deploy allow users to live measure distance, area, and volume.
Construction firms can use these tools to calculate the quantity of stockpiles, estimate material costs, and collect other valuable data without actually having to be at the development site.
Landscaping Companies can easily find the boundaries of a particular property, making their job much easier and time which is money.
Software programs also can use the data from the aerial photos to construct 3D models, DEM's(Dtigital Elevation Models) with contours which is another powerful tool for construction firm, making sure the ground slopes the correct way avoiding flooding issues.
Monitor Crop Health
The agriculture industry is additionally seeing an enormous benefits from orthomosaics.
Specialized drones have multispectral cameras that gather data from specific bands of sunshine , like Red, Green, Blue, Red Edge, and Near-Infrared.
The added data from multispectral camera systems along side the power to urge orthomosaic maps allows farmers to get an in depth understanding of their vegetation health with an NDVI index.
They can use this data and treat areas that require immediate attention and have a more successful crop season.
Along with inspecting crops, orthomosaics are great for performing aerial inspections of just about any structure and other facilities.
They can be used for inspecting roofs, church spires, solar installations, buildings that are in need of reconstruction, and more.
Legal Proceedings and Court Cases
Orthomosaics are occasionally utilized in legal cases too.
Orthomosaics provide the necessary imagery such as a property size and location needed for the legal proceedings.
Count Cattle, Monitor Supplies, Measure Roofs, & More
You can use orthomosaics to count trees, monitor forest health, count cattle, determine the amount of cars during a parking zone , see the supplies on a construction site, measure rooftops, make annotations, then far more counting on app or program you’re using.