文章內容
DJI Terra is an easy-to-usedroneMapping software designed to help industry professionals transform real-world scenarios into digital assets. Check out our exclusive dataset to see the power of DJI Terra.
Update (March 17, 2022): New firmware update (version: 3.3.4) includes improvements to LiDAR processing, DSM downsampling, and many other fixes. It follows the January update that made mapping in DJI Terra faster and smoother
DJI Terra is a very powerful tool for creating highly detailed 3D models – especially for visual inspection and for first-stage analysis using a suite of measurement tools.
DJI Terra can also be used for LiDAR drone mapping to help build dense point cloud representations of the real world.
What is DJI Terra?
DJI Terra is a drone survey software tool that converts drone data into digital 3D models (shown below) and 2D maps for easier analysis and decision-making.
This software package enables businesses and organizations using DJI drone technology to capture, visualize and analyze aerial imagery for a variety of applications in the public safety, construction, infrastructure, agriculture and film industries.
DJI Terra compatible includesPhantom 4 RTKA series of DJI products including. The full list of compatible drones/cameras will be highlighted later in this blog.
DJI Terra has four licenses - Agriculture, Professional, Power and Cluster. New in 2020, the Electricity License is designed to provide new optimizations for powerline modeling, helping enterprise users create detailed 3D reconstructions of thin powerlines.
Introduced in 2021, cluster licenses allow multiple computers to perform computations simultaneously, significantly improving efficiency and suitable for large-scale rebuilds.
Scroll further down this blog to see the differences between the four licenses.
Under the license, Terra tools will allow organizations to map in real-time and generate high-quality 2D and 3D reconstructions and measurements, among other things.
DJI Terra drone photogrammetry
Our sample dataset demonstrates the power of DJI Terra in photogrammetry; the art of capturing high-resolution photos to reconstruct surveyed areas.
DJI Terra's 3D models and 2D orthomosaics (more on this later) can be used in industrial applications such as reconstructing car crashes, tracking progress and finding errors in construction projects or conducting large-scale critical infrastructure inspections of bridges and roads.
Photogrammetric data can also be used to make calculations and measurements (again, more on that later).
3D Modeling with DJI TERRA
One of the most effective aspects of the DJI Terra is its ability to reproduce crisp and true-to-life 3D models—especially with high-resolution 45MP full-frameP1 camerawhen used together.
In many ways, it's close to reality capture. Take this image as an example, which shows in high detail one of our survey sites – a farm in Northumberland, UK – where the data was collected by P1.
Not only are the buildings crisp and clear – including key details of the brickwork and varying roof conditions – but the model fully replicates smaller items in the scene, such as the dumpster in the lower right corner of the image.
Having such a powerful dataset is really valuable to the people who use it for decision making and information sharing.
DJI Terra further recognized for its 3D modeling capabilities compared to other software
Terra models are very complex.
The entire shed is fully replicated, with clean, crisp edges and no distortion or warping. At the same time, the map has enough detail that the viewer can clearly see the items in the shed to the right of the image.
The model built in DJI Terra is a more defined, higher-resolution creation.
This in turn helps pick out small details. Note, for example, how the Terra dataset replicates three chimneys, giving the structure texture and shape and accentuating its complex features. Meanwhile, you can clearly see the letterbox, widow and even the doorknob on the front door.
By contrast, alternative software cannot replicate these fine details. Again, this isn't a bad mod, but the chimney is more blocky and has the least amount of texture. While letterboxes can be distinguished, the front door lacks windows and door handles.
Interestingly, the data collected for both missions was done automatically, each time during a drone flight using the P1's smart tilt capture mode - which only captures basic images.
Therefore, adding manual data capture to complement the initial flight will further enhance these models on both software platforms.
2D Ortho Tessellation
Like 3D models, DJI Terra creates crisp and detailed 2D orthomosaics.
This series of images was taken from an altitude of 80 meters using a P1 and a 35mm prime lens (the P1 can also use a 24 or 50mm prime lens).
The combination of the DJI Terra and P1 is so good that when zoomed in to the ortho mosaic you can count the number of holes in the bricks (third image).
This is incredible detail; the detail can greatly help analysts find subtle or finer points on a digital map – such as during a crime scene investigation or finding problems on a construction site.
And the fact that you can get this level of detail from an 80m flight height greatly increases the efficiency of data collection - covering more ground at any given time.
In fact, in our tests, the P1 yielded a ground sample distance of 1.18 cm at 80 meters. It even achieves a GSD of 0.63 cm from 50 meters - which will result in a higher resolution map!
DJI Terra also features real-time mapping, allowing drone pilots to quickly generate 2D orthomosaics while the drone is flying, ideal for time-sensitive tasks where situational awareness is critical and decisions need to be made within minutes.
Although, we did not use this real-time capability during the M300 RTK-P1 mission; instead, we used DJI Pilot and processed the data after the Terra mission.
Analysis tools for DJI Terra
In addition to map and model creation, DJI Terra helps users analyze data and generate instant insights with easy-to-use measurement and analysis tools, including linear distance, surface area and volume estimates, and coordinates.
These tools are great for first-stage analysis.
The ability to measure volumes and areas is very common for storage and construction planning. Instead of exporting raw data from Terra and performing analysis in GIS software, you can directly access the analysis capabilities of Terra itself.
Volumetric measurements are a common use of photogrammetric data because the density of the data is much higher than what can be achieved with terrestrial measurements, which ultimately means it is more accurate.
Likewise, the ability to count items and measure coordinates is an intuitive and absolute way to collect data from the field.
Additionally, to improve team communication and reporting on ongoing projects, annotation tags can be edited and shared using DJI Terra.
Ground control points can also be imported into WGS84 or any coordinate system.
fast processing
DJI Terra is local-based software, so there is no need to upload photos. Uploading only comes into play when working on a cloud-based platform, since you need to upload to the internet.
With this in mind, it took us just over 8 hours to process the 390 images collected from the farm site, and 14 and a half hours to process the 621 images from our second test site in the North East of England.
The P1's Smart Tilt Shooting Mode can help reduce post-processing time on the 50% by collecting only essential images.
For example, P1 (90°, standard image; 45°, oblique image) only collected 400 images during Smart Oblique Capture Mode on the farm site.
In another test, the P1 captured nearly 1,000 images at the same location while flying in dual grid mode with the gimbal fixed at 60°. This in turn is reflected in the post-processing speed, with double grid tasks taking twice as long.
DJI TERRA LiDAR
DJI Terra fuses IMU and GNSS data for point cloud and visible light calculations, in addition to POS data calculations so you can easily generate reconstructed models and accuracy reports.
It also provides fast data processing - we can process data from a 30-minute task in just 3 minutes.
The results of it? A solid model. For example, the image below shows a fairly complete reproduction of the survey site – especially when looking at the tops of the buildings, which appear dense and complete.
Granted, some areas of the model are not very comprehensive, such as the side of the barn, but this depends on the fact that the head is fixed at a 90° angle during flight. This makes it more difficult to capture a dense set of points to fully flesh out the building's side profile.
However, the reorientation of the gimbal will significantly increase the strength of the point cloud in these regions.
The DJI Terra-L1 combo also helps identify intricate details on survey sites, such as power lines in front of farm buildings. As these images show, this is not the case with maps created using photogrammetry, which miss these power lines because they are too finely detailed.
For post-processing, DJI Terra supports the following color modes:
- visible
- Reflectivity
- high
- return number
On the data side, L1 stores raw information in .dat format. Once processed through Terra, it is converted to .las format, which is a standard point cloud format.
This raw data is processed with all RTK and IMU position data from L1 to produce accurate output.
One thing to note is that raw location and LiDAR data files always need to be processed by Terra, as laser scan data is developer-specific and cannot be processed in third-party applications.
DJI has stated that there is room for third-party applications to be compatible with their initial data processing, so please be aware of this space.
DJI Terra - Which drones and cameras are compatible?
DJI Terra provides seamless connectivity to your DJI drone fleet.
DJI Terra supports the following DJI aircraft for route planning:
- Phantom 4
- Phantom 4 Pro
- Phantom 4 Pro V2.0
- Phantom 4 Pro + V2.0
- Phantom 4 Premium
- Phantom 4 RTK (Monitor Remote Control)
- Phantom 4 RTK (remote control without display). Only supports import of detailed inspection plan routes
- Matrice 300 RTK + H20 Series Payloads: Only supports import of detailed inspection plan routes.
- Mavic 2 Enterprise Advanced: Only supports importing detailed inspection plan routes.
For the Phantom 4 Multispectral, DJI Terra supports NDVI, GNDVI, NDRE, LCI, and OSAVI, but does not have the Vegetation Index Calculator feature. After the update, Terra also supports radiometric correction on P4 Multispectral.
Use DJI Terra to process from:
- Phantom 4 series
- Zenmuse P1
- Zenmuse L1
- Zenmuse X7
DJI Terra Licensing Program
DJI Terra offers four licensing plans – Agriculture, Professional, Power, and Cluster (for computing multiple devices simultaneously to significantly reduce processing time).
Some licenses are available online, while others are available offline.
- Online mode:Connect your device to the internet regularly to verify permissions and use paid features.
- Offline mode:For users with high information security requirements, paid functions can be used without connecting to the Internet.
The following online features are not available in offline mode:
- Unlock the GEO region
- Map loading and location search
- If you do not log in to your DJI account, some flight control functions in DJI Terra will be limited.
Why choose Zhenhe:
- We have creative and rich photography experience: when operating the aerial camera, Zhenhe always has two people to ensure the best picture during the flight, but not neglect the flight safety
- We are efficient: most of our cases are completed and sent to clients within 48 hours
- All drones are insured, and all pilots have a certificate from the Civil Aviation Administration
About Zhenhe:
The core values are: integration, integrity, professionalism, innovation, and thinking about problems from the perspective of customers, thinking about the possible reactions of users and audiences, and delivering the most complete solutions after continuous adjustment.
