For some of the copter data processing folks Agisoft Photoscan turns out to be the most important tool/software to calculate point clouds, orthoimages and nadir data mosaics from copter photographs.
Problem: very long processing times with dense point cloud calculations with high or ultra-high settings (full resolution image matching with SfM (Structure from Motion) algorithms).
Some nice net finds show how multicore processing has its limits and why you should invest into GPU performance … and in high end 3D graphic cards.
Combining more than 20 CPU cores doesnt seem to speed up the process and combining more than 4 GPU systems also doesnt seem to help. There is only a minimal speed increase when you add more CPUs and or more GPUs when a 24 core system is already installed.
It boils down to a dedicated system with 2-4 Graphic cards with 3D acceleration (GTX-1080ti cards from Nvidea or if you can afford it a TESLA p100 based system), with approx 64-128 GB RAM and a dual i7 system setup.
mtk – Sören
Using DroneDeploy and the POI mode of DJI (this article was first published on jenacopterlabs.de).
Have been doing some leaf-off flights now in March on one of my favorite sites for complex tree crown point cloud mapping. To add to the leaf-on data from last autumn.
Fig.: Leaf-Off point cloud with combined height color coding and reflectance color coding.
This time I also checked the full automatic flight modi using the POI (Point Of Interest) mode from DJI and Drone Deploy with the P4Pro and the P3A.
Both work perfectly although I believe the POI mode can be dangerous when its done with low altitudes. You have to carefully check that the radius is free from obstacles when you define the center position, altitude and distance from center (radius) for the POI flight. When POI is started it begins with comparably low speeds. You can modify the speed setting when the POI mode started. Unfortunately you cannot modify this stetting before you start. Tuning the speed on an iPad or (even more difficult – on an iPhone) is kind of dangerous because you easily move the slide too much to higher speeds than wanted and the copter will immediately accelerate and start circling your POI object like crazy until you managed to move the slider to slower speeds. There is however always this stop button to kill the POI mode – this is handy and needed sometimes. When you press the stop button the copter stops the POI mode completely and waits for new commands.
Continue reading “Drone Deploy and DJIs POI Mode copter image acquisitions”
The higher resolution version of the Schlachtensee Pano shot / panorama from early February. This was a magic week. Temperatures and light were just perfect and the ice was incredible untouched. This pano is from the P3A.
For those not familiar with the Berlin south west. The Schlachtensee region is known in Berlin as the area where the people who love dogs used to have some conflicts with those that go for a run and/or the other way around. I think the conflict has been cooling down now somewhat fortunately! In summer its great to have a swim here early in the morning. Skating in winter only works every 5-10years – so these days in February were kind of unique. (Pano from 4 different shots: resampled to 4300×1300).