PRISM·lidarcloud — User manual

From a raw point cloud to survey-grade, client-ready deliverables — in the browser. All docs · REST API · Open the app

1 · Sign in

Enter your email and we send a one-time sign-in link — no password to manage. The link signs you into your account on any device; your jobs and usage stay private to your account. Open your email (Account) any time to see usage, manage API keys, and review past jobs.

2 · Upload & options

Drop a .las or .laz on Upload — no conversion or preprocessing needed. The one-click defaults run the full suite; open Options to change any of:

OptionDefaultWhat it does
AlignmentUSGS 3DEPauto double-round co-registration (H→V→H→V) to a reference: 3DEP (auto-fetched national model, default), a second cloud you upload (paired), an existing dataset, or none.
Change detectiononwith a reference, compute erosion / deposition / canopy change (post-processing — 0 extra jobs). Against 3DEP it runs our engine on the raw 3DEP point cloud for a same-engine, apples-to-apples DEM & canopy comparison.
Semantic classificationonlabel the cloud into the 8 ASPRS classes.
DEM resolutionautoauto / 25 cm / 50 cm / 1 m.
Vertical datumNAVD88NAVD88 orthometric heights (GEOID18, rigorous per-cell) by default; or keep WGS84 ellipsoidal. Outside the contiguous US (no GEOID18 coverage) it falls back to ellipsoidal with a note.
Visual colorizationautofor clouds with no camera RGB, drape natural colour from public imagery (§7). Visual only.
Accuracy reportonWord report (ASPRS 2014/2023) with an AI-assisted interpretation.
CAD bundleonDXF contours + LandXML surface (State Plane ftUS / NAVD88) in the download.
Email meonclose the tab — we email you when the job finishes.

3 · While it runs

Processing runs on its own cloud machine; a progress bar tracks the stages. You can keep the tab open to watch, or close it — if "Email me" is on, we notify you (and the link signs you back in to the result on any device). Typical jobs finish in minutes; very large clouds take longer.

4 · Inspect

The right panel is a numbered step list — Process · Explore · Validate · Align · Report · Export — with a single detail pane for the selected step and a Run summary that lists the pipeline stages with their status. The list advances as a job runs and tracks which steps you have completed.

5 · Accuracy & validation

From the Accuracy panel:

The uncertainty raster ships with every DEM: low values = well-supported bare ground; high values = where canopy occlusion forced interpolation. Use it to know which parts of the surface to trust most. It is a relative confidence map by default; it is calibrated to an absolute ±cm answer only when you supply surveyed control points (above), which tie the surface to a known datum and yield a numeric vertical accuracy statement.

6 · Alignment, datums, CAD & change detection

Alignment vs validation: co-registration runs automatically on upload — a double round that solves horizontal then vertical, repeated twice (H→V→H→V), on stable ground. The second round verifies the residual from the first. Validation (§5) is the separate post-alignment accuracy check: it measures how well the co-registered product agrees with the reference. Re-run alignment manually from the Align step against a different reference, then re-validate.

Datums/CAD: choose NAVD88 (GEOID18) for orthometric heights; the CAD bundle exports DXF contours + a LandXML surface in the correct Florida State Plane ftUS zone (county-aware) for direct ingest into civil/survey software.

Change detection & apples-to-apples 3DEP: the default comparison is against the USGS 3DEP reference. Alignment and validation use the raw 3DEP DEM (USGS's own product, built by their algorithm) — an honest external cross-check. Change detection runs OUR engine on the raw 3DEP point cloud, producing a same-engine DEM (and canopy surface) so the change — erosion/deposition volumes (with a printed minimum level of detection) and canopy loss/gain — is truly apples-to-apples rather than confounded by differing processing. (When the 3DEP point cloud is unavailable for the area, change falls back to the screening-grade 3DEP DEM.) You can also process against a prior survey of your own (paired upload). 3DEP comparisons are labelled screening-grade (coarse grid, unknown collection epoch). Results render as maps + stats + report pages.

7 · True-colour (visual colorization)

LiDAR is often flown without a camera, so the cloud has no colour. PRISM can drape it in natural colour from flight-time public imagery — date-matched and cloud-masked — for an intuitive 3D view and a colourised cloud in your download.

8 · Download

The product zip contains the DEM, DSM, CHM, and uncertainty rasters (GeoTIFF), the AOI boundary, the classified cloud, the accuracy report (Word), and the CAD bundle (DXF + LandXML) — plus alignment + change products and the colourised cloud when those ran.

9 · Automate it (API)

Everything above is scriptable: create an API key on your account page, install the client (pip install https://app.lidarcloud.app/downloads/prism_lidarcloud-1.0.0-py3-none-any.whl — PyPI publish pending), then prism run scan.las --align 3dep -o out.zip, or use the Python Client / plain REST. Full reference: API docs.

10 · Data sources & licensing

Reference + imagery come from open, commercially-usable public sources: USGS 3DEP (US public domain), Sentinel-2 (Copernicus — free and open, commercial use permitted), and NAIP aerial where available (USDA public domain). Your uploaded data is private to your account and retained for 14 days, then purged.

lidarcloud.app