Reality capture is a term used to describe the process of digitally capturing, documenting, and representing the physical world. This is done using a range of technologies and techniques, most commonly laser scanning, photogrammetry, and unmanned aerial vehicles (UAVs) equipped with lidar or camera sensors.

Reality capture typically involves the use of specialised equipment and software to collect data about the physical environment. This data can be used to create digital 3D models, point clouds, maps, and other visualisations that accurately represent the real-world objects and spaces being captured.

Reality capture has many applications across a variety of fields, including architecture, engineering, construction, archaeology, and urban planning. It can be used to create detailed, accurate representations of buildings, landscapes, archaeological sites, and other physical environments. It can also be used to monitor and track changes to the physical environment over time, such as the progress of a construction project or the erosion of a natural landscape.

Key Reality Capture Technologies

Several different technologies are used for geospatial reality capture, each suited to different scales and environments:

• Terrestrial laser scanning (TLS): A static ground-based scanner emits laser pulses and measures the time-of-flight of returns to build a dense, millimetre-accurate point cloud of the surrounding environment. TLS is commonly used for heritage documentation, infrastructure inspection, and detailed site surveys.
• Mobile laser scanning (MLS): Laser scanners are mounted on a moving vehicle or backpack and combined with GNSS and inertial measurement unit (IMU) sensors to capture continuous 3D data along a corridor. MLS is widely used for road surveys, utility mapping, and city modelling.
• Photogrammetry and Structure from Motion (SfM): Overlapping photographs taken from multiple angles are processed by software to reconstruct a georeferenced 3D model. SfM photogrammetry is the computational method that drives most drone-based reality capture workflows, producing dense point clouds, orthophotos, and digital elevation models (DEMs).
• UAV (drone) surveys: Unmanned aerial vehicles carry cameras or lidar sensors and can rapidly survey large areas that would be difficult or dangerous to access on foot. Drone-captured data is processed using photogrammetry or lidar processing software to produce orthophotos, DEMs, and 3D meshes.
• Airborne lidar: Lidar sensors mounted on fixed-wing aircraft or helicopters are used for large-area topographic mapping, forestry, floodplain modelling, and corridor mapping. Airborne lidar routinely covers hundreds of square kilometres in a single flight and produces georeferenced point clouds classified into ground, vegetation, and structure returns.

Reality Capture Outputs

The primary raw output of most reality capture workflows is a point cloud — a set of georeferenced x, y, z coordinates (often with colour and intensity values) representing the measured surfaces. Point clouds are then processed into derivative products depending on the application:

• 3D meshes: A surface model built from the point cloud, often textured with photographic imagery.
• Orthophotos: Geometrically corrected aerial images with a consistent scale, suitable for measurement and GIS integration.
• Digital elevation models (DEMs): Raster grids representing ground or surface elevation, derived from classified point clouds or photogrammetric processing.
• BIM models: Intelligent 3D building models created from scan data, used in architecture, engineering, and construction workflows.

40 Applications of Reality Capture

1. Architecture and construction: reality capture can be used to create detailed 3D models of buildings and other structures, which can be used for design, planning, and construction.
2. Heritage and cultural preservation: reality capture can be used to create digital records of important historical and cultural sites, allowing for their preservation and study.
3. Geographic information systems (GIS): reality capture can be used to create detailed 3D models of the landscape, which can be used for mapping, navigation, and environmental analysis.
4. Urban planning: reality capture can be used to create detailed 3D models of urban environments, which can be used for city planning, infrastructure development, and public safety.
5. Virtual and augmented reality: reality capture can be used to create realistic 3D models of real-world environments, which can be used for immersive virtual and augmented reality experiences.
6. Cinematography and visual effects: reality capture can be used to create digital assets for use in film and television productions, allowing for more realistic and convincing special effects.
7. Industrial design and engineering: reality capture can be used to create detailed 3D models of products and machinery, which can be used for design, testing, and manufacturing.
8. Archaeology: reality capture can be used to create detailed 3D models of archaeological sites and artefacts, allowing for non-destructive study and analysis.
9. Virtual tours and real estate: reality capture can be used to create virtual tours of properties, allowing for more immersive and engaging experiences for potential buyers.
10. Criminology and forensic investigation: reality capture can be used to create detailed 3D models of crime scenes, which can be used for analysis, documentation, and courtroom presentations.
11. Search and rescue: reality capture can be used to create detailed 3D models of disaster areas, which can be used to plan and coordinate search and rescue operations.
12. Medical imaging and surgical planning: reality capture can be used to create detailed 3D models of the human body, which can be used for surgical planning and training.
13. Conservation and environmental protection: reality capture can be used to create detailed 3D models of natural environments, which can be used for monitoring and conservation efforts.
14. Traffic and transportation engineering: reality capture can be used to create detailed 3D models of roads and other transportation infrastructure, which can be used for planning, design, and analysis.
15. Education and training: reality capture can be used to create realistic 3D models of real-world environments, which can be used for immersive training experiences in a variety of fields.
16. Archaeological excavation: reality capture can be used to create detailed 3D models of archaeological sites, which can be used to plan and coordinate excavation efforts.
17. Land surveying and mapping: reality capture can be used to create detailed 3D models of the land, which can be used for property boundary determination, topographic mapping, and other surveying applications.
18. Manufacturing and quality control: reality capture can be used to create detailed 3D models of products, which can be used for quality control, inspection, and assembly.
19. Disaster response and recovery: reality capture can be used to create detailed 3D models of disaster areas, which can be used to plan and coordinate response and recovery efforts.
20. Virtual museum exhibits: reality capture can be used to create digital replicas of museum artefacts, allowing for more immersive and engaging virtual exhibits.
21. Entertainment and gaming: reality capture can be used to create realistic 3D models of real-world environments, which can be used for immersive gaming and other entertainment experiences.
22. Retail and e-commerce: reality capture can be used to create detailed 3D models of products, which can be used for online product demonstrations and virtual try-ons.
23. Accident and crime scene reconstruction: reality capture can be used to create detailed 3D models of accident and crime scenes, which can be used for investigation, analysis, and presentation in court.
24. Environmental and geological modelling: reality capture can be used to create detailed 3D models of natural environments and geological formations, which can be used for analysis and simulation.
25. Infrastructure inspection and maintenance: reality capture can be used to create detailed 3D models of infrastructure such as bridges, tunnels, and power plants, which can be used for inspection and maintenance planning.
26. Cultural heritage documentation: reality capture can be used to create detailed 3D models of important cultural heritage sites and artefacts, which can be used for documentation, preservation, and study.
27. Landscape and garden design: reality capture can be used to create detailed 3D models of landscapes, which can be used for design and planning of gardens, parks, and other outdoor spaces.
28. Product design and development: reality capture can be used to create detailed 3D models of products, which can be used for design, testing, and prototyping.
29. Interactive marketing and advertising: reality capture can be used to create immersive and interactive marketing and advertising experiences, using realistic 3D models of products and environments.
30. Emergency response and preparedness: reality capture can be used to create detailed 3D models of emergency response facilities and routes, which can be used for training and planning.
31. Archaeological site management: reality capture can be used to create detailed 3D models of archaeological sites, which can be used for site management and preservation.
32. Health and safety training: reality capture can be used to create realistic 3D models of hazardous environments, which can be used for training and simulation of emergency situations.
33. Security and surveillance: reality capture can be used to create detailed 3D models of security and surveillance areas, which can be used for monitoring and analysis.
34. Military training and simulation: reality capture can be used to create detailed 3D models of military environments, which can be used for training and simulation purposes.
35. Land use and zoning planning: reality capture can be used to create detailed 3D models of urban environments, which can be used for land use and zoning planning.
36. Virtual events and conferences: reality capture can be used to create realistic 3D models of event venues, which can be used for virtual conferences and meetings.
37. Virtual interior design: reality capture can be used to create detailed 3D models of interiors, which can be used for virtual interior design and home staging.
38. Cultural and historical research: reality capture can be used to create detailed 3D models of historical sites and artefacts, which can be used for research and analysis.
39. Virtual education and training: reality capture can be used to create realistic 3D models of real-world environments, which can be used for virtual education and training programmes.
40. Asset management and inventory: reality capture can be used to create detailed 3D models of assets, which can be used for inventory and asset management purposes.

In summary, reality capture is the process of digitally documenting, analysing, and representing the physical world using specialised equipment and software. It has applications across a wide range of fields and can produce detailed, accurate representations of physical spaces and objects in the form of point clouds, 3D models, orthophotos, and elevation models.