Generate Orthophotos, DEMs & Point Clouds with ODM
- Anvita Shrivastava
- Jul 20
- 4 min read
Updated: 6 days ago
The use of drones for mapping purposes has fundamentally changed the way data is collected and analyzed. Drones allow surveyors to obtain quick, high-quality aerial images at a reasonable cost. However, the raw images require additional processing to become effective geospatial products.
OpenDroneMap (ODM) is among the most widely used open-source photogrammetry software tools used for processing drone images into GIS maps. Thanks to ODM, surveyors, GIS professionals, engineers, environmentalists, and researchers can produce high-quality geospatial datasets without purchasing expensive proprietary software.
What Is OpenDroneMap?
OpenDroneMap (ODM) is an open-source aerial imaging program that converts overlapping images taken from various drones into georeferenced maps. The software utilizes computer vision and the Structure from Motion (SfM) and Multi-View Stereo (MVS) techniques in reconstructing 3D models.
ODM works with imagery from the following drones:
DJI drones
Autel drones
Skydio drones
Parrot drones
SenseFly drones
Customized UAVs
Drones with RTK and PPK capabilities
This software comes in downloadable form for Windows, Linux, and macOS platforms, making it usable by individuals and businesses.
Why Use OpenDroneMap?
OpenDroneMap has many benefits compared to commercial photogrammetry software.
Free and Open Source
There are no costs associated with the software, making ODM a great choice for any start-up, research institution, or government department.
High-Quality Outputs
ODM is capable of producing state-of-the-art Orthophotos, Digital Surface Models (DSM), Digital Terrain Models (DTM), point clouds, 3D texture meshes, and contour lines.
Flexibility in Deployment
ODM can run on desktops, Docker, cloud servers, Linux laptops, and automated workflows.
GIS Integration
Finally, ODM results can be directly integrated into various GIS platforms, including ArcGIS Pro, QGIS, Global Mapper, GRASS GIS, AutoCAD Civil 3D, and CloudCompare.
What Outputs Does OpenDroneMap Generate?
Orthophotos
Orthophotos are aerial images that have been geometrically rectified such that the scale of the image remains constant throughout.
Advantages are:
Distances can be measured accurately.
Areas can be calculated accordingly too.
Infrastructure can be viewed easily.
Land use can be evaluated.
Crops can be analyzed.
Common output format:
GeoTIFF
Digital Elevation Models (DEMs)
OpenDroneMap produces two types of elevation models.
It consists of:
Structures.
Vegetation.
Vehicles and
Terrain.
Common uses include:
City planning.
Flood forecasting.
Solar projects and
Telecommunication.
Depicts the Earth's surface devoid of any vegetation and buildings.
Common uses are:
Hydro-geomorphological studies.
Watershed study.
Road building and
Earthworks.
Output format:
GeoTIFF
Point Clouds
ODM offers dense 3D point clouds representing millions of points in unique formats.
Common formats include:
LAS
LAZ
PLY
Point clouds can be used in:
Mining
Construction
Forestry
Digital Twins
Cultural heritage sites.
3D Meshes
The ODM generates textured 3D models that are valid for visualization and simulation.
Formats that are supported are:
OBJ
GLTF
Applications include:
Building visualization
Architecture
Virtual tours
Reality capture
Contour Maps
Contour lines can be produced from the elevation models for:
Civil engineering
Topographic mapping
Drainage design
Landscape planning
How OpenDroneMap Operates
ODM employs an advanced photogrammetry process.
Step 1: Uploading Images
Capture drone images with considerable overlap, which are as follows:
75-85% overlap from front to back,
65-75% overlap from left to right.
Optimum overlap enhances the quality of output.
Step 2: Detection of Key Features
ODM processes many images simultaneously and finds distinct features from each of the images.
These include interesting points such as:
Corners of buildings,
Rocks,
Trees in the landscape,
Roads,
Convexity of surfaces, and others.
Step 3: Matching of Images
Matching algorithms are used to match similar features in multiple images at the same time.
Step 4: Generating a Sparse Point Cloud
A sparse 3D visualization is built for the purposes of determining the orientation of the cameras and the scene geometry.
Step 5: Creating the Dense Point Cloud
Utilizing Multi-View Stereo (MVS), ODM produces a dense point cloud, with a great number of points contained in it.
Step 6: Creation of Surface Models
ODM creates such models as DSM, DTM, and meshes.
Step 7: Generation of Orthophotos
As a conclusion, georeferenced orthophotos are generated from the adjusted images.
Installing OpenDroneMap
One of the easiest installation methods is Docker.
docker pull opendronemap/odmRun ODM:
docker run -ti \
-v /home/user/images:/datasets \
opendronemap/odmAlternatively, users can install:
Native Linux version
Windows installer
WebODM interface
OpenDroneMap Limitations
ODM is indeed strong; however, several aspects need some consideration:
Large datasets have to be processed, and this requires a high-performance CPU, RAM, and storage.
The time required for processing can be greater than the time required by some commercial solutions using GPU acceleration.
The outcome of the work depends on the quality of the captured images and redundancy.
Experienced users may want to use command-line processing instead of the much more intuitive WebODM, though.
OpenDroneMap can be defined as a robust solution in photogrammetry that is open source, allowing its users to change the drone images into top-grade orthophotos, DEMs, clouds of points, and 3D models. Due to its ability to be adapted, its meaningful interface, and the ability to work with the leading GIS systems, OpenDroneMap is an ideal solution for surveying, construction activities, agriculture, mining, forestry, and environmental analysis.
No matter if you are a GIS expert, drone operator, researcher, or developer, OpenDroneMap is a financially successful approach to working with quality geospatial data and blending it with other processes.
To learn more about OpenDroneMap and its geospatial capabilities, click here.
For more information or any questions regarding the LizardTech suite of products, please don't hesitate to contact us at:
Email: info@geowgs84.com
USA (HQ): (720) 702–4849
(A GeoWGS84 Corp Company)
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