Photogrammetric restitution using drone
Modern photogrammetry currently uses autonomous vehicles, the most common currency is to use software such as Pix4d Mapper for the derivation of products.
Maybe you are wondering. Can you perform photogrammetric restitution using drones?. If you have done it before with satellite images, or manned flights, you know what I mean, and if you are starting in this, in the photogrammetric restitution you need a stereo pair of images, with some special glasses let's say basically some anaglyphs glasses that you can see in 3D, like in the movies!
Now imagine drawing in 3D each of the elements that are taken in the photographs with your anaglyphic glasses and 3D mouse.
Remember when you fly with a drone, there are a lot of images. If you want to perform the stereo digitization it is pair per pair of images, we also clarify by the nature that fixed wings fly the angles compared with a copter are more noticeable (pitch, roll, yaw).
To make the adjustment, you should consider the coordinates and angles of the images (omega, phi, kappa) control points if there were, and also focal length, main point, radial and distortion coefficients that correspond to: f, px, py, k1, k2, k3, k4 and p1, p2. There are important! because those allows correcting the model, otherwise the generated model will not be correct and parallax errors will occur. It is important to mention that parallax will always be by technique, especially in high structures, where the floating mark moves to the height of it, but the problem is when there is a parallax that does not allow you to work.
I have seen how they have tried to merge restitution software in old versions that are designed for ideal images (satellite, manned.) with the images acquired using a drone, you cannot form complete models!. Do you imagine that manually you have to join pair by pair? How many images does a drone flight have? What a headache!
Photogrammetric restitution is a technique that requires expertise, time and effort. Do you evaluate if your project requires it?
What about if you digitalize 2D on your orthophoto?. What is your cost-benefit relationship?
If there are objects in your cartography that you can identify in 2D, then you digitize it!, but otherwise, I recommend that you locate software that has already resolved the photogrammetric restitution using drones, believe it or not, there is not many that have been solved. I recommend Photomod UAS that module has a completed process.
By: Bethania Peña
LAS General Manager Perú.
For more information visit: www.latitudeas.com
Phone: +1 347 960 6444