Glossary
Swyvl terms
Capture session A grouping of files acquired at the same time — one drone flight, one scan day, one photogrammetry run. Sessions give clients context about which data came from which field visit.
Client approval A formal sign-off recorded when a client clicks Approve on a share link. Creates a timestamped record in the Activity tab. You receive an email notification. Clients can also request changes, which records their feedback message.
Delivery What clients call a share link — a branded web page containing spatial data from one or more capture sessions.
Organisation The top-level account entity. Represents your company. Contains all workspaces. Settings like your logo and data region apply organisation-wide.
Share link A public URL that delivers a curated set of spatial files to a client. Clients view and download files in a browser with no login required. Accessible from the Sharing tab.
Site A named physical location on the map. All files must belong to a site. Sites appear as pins on the map home screen.
Workspace Represents a client. Sites, files, and share links belong to a workspace. Each workspace has its own branding (accent colour, header message).
Spatial data terms
3D Tiles
An open standard from the Cesium consortium for streaming massive 3D datasets — point clouds, photogrammetry meshes, building models — in a browser. Files are stored as a directory with a tileset.json index. Swyvl accepts them as a ZIP archive.
Drone video Video footage captured by an unmanned aerial vehicle (UAV/drone). Usually MP4, sometimes with embedded GPS telemetry. Swyvl plays drone video in the browser with a standard video player.
E57 A standardised file format for 3D point cloud data and images from 3D scanners. Common output from FARO Focus, Leica BLK, and Z+F scanners.
Gaussian splat / 3DGS
A novel 3D representation technique that reconstructs a scene as millions of small Gaussian “blobs” rather than triangles or points. Produces photorealistic real-time renders from photogrammetry or NeRF captures. File formats: .splat, .spz.
GeoTIFF A TIFF image with embedded geospatial metadata (coordinate reference system, bounding box). Used for orthomosaics, elevation models (DTM/DSM), and aerial photography.
KML / KMZ Keyhole Markup Language — an XML-based format for geographic data (placemarks, paths, polygons, image overlays). KMZ is the zipped version. Common output from DJI drones, survey instruments, and GIS software.
LAZ Lossless compressed LAS format. Reduces file sizes by 5–10× with no quality loss. Recommended for delivery over LAS.
LAS The industry-standard file format for lidar point cloud data. Stores XYZ coordinates, intensity, classification, and return information for each point. Maintained by the ASPRS.
Lidar Light Detection and Ranging — a remote sensing technology that measures distances using pulsed laser light to generate 3D point cloud data. Used in terrestrial laser scanning (TLS) and airborne lidar surveys.
Multipart upload An upload method that splits large files into chunks and sends them in parallel. Swyvl uses multipart upload automatically for files over 100 MB. Based on S3 multipart upload.
Orthomosaic A geometrically corrected aerial image composed of many overlapping drone photos, stitched into a single georeferenced raster. Common formats: GeoTIFF. Viewed in Swyvl with the Leaflet map viewer.
Point cloud A set of data points in 3D space, each with XYZ coordinates and often additional attributes (intensity, RGB colour, classification). Produced by lidar scanners, photogrammetry, and depth cameras. Formats: LAS, LAZ, E57.
Presigned URL A time-limited URL that grants temporary access to a file in object storage without requiring credentials. Swyvl uses presigned URLs to securely serve files to viewers and downloads. URLs expire after 1 hour.
Row-level security (RLS) A database feature that restricts which rows a user can see or modify based on their identity. Swyvl uses PostgreSQL RLS to enforce data isolation between organisations and workspaces at the database level.
SPZ
A compressed Gaussian splat format. Smaller than .splat with equivalent visual quality. Preferred for delivery.
Tileset
In the context of 3D Tiles, a tileset is the directory of tile data files with a tileset.json index. In the context of map viewers, a tileset is a collection of image tiles served at different zoom levels.
Acronyms
| Acronym | Meaning |
|---|---|
| AGL | Above Ground Level |
| ASPRS | American Society for Photogrammetry and Remote Sensing |
| CRS | Coordinate Reference System |
| DTM | Digital Terrain Model |
| DSM | Digital Surface Model |
| DEM | Digital Elevation Model |
| EPSG | European Petroleum Survey Group (coordinate system registry) |
| GCP | Ground Control Point |
| GIS | Geographic Information System |
| GNSS | Global Navigation Satellite System |
| IMU | Inertial Measurement Unit |
| LiDAR | Light Detection and Ranging |
| RPC | Rational Polynomial Coefficient |
| RTK | Real-Time Kinematic (GPS precision method) |
| UAV | Unmanned Aerial Vehicle (drone) |
| WGS84 | World Geodetic System 1984 (standard GPS coordinate system) |