Frequently asked questions

Neurones 3D (N3D) is point cloud processing software for Windows. It opens survey files (LAS, LAZ, COPC, E57, PLY and more), BIM and CAD models (IFC, STEP, USD) and Gaussian splats, and turns them into deliverables: classified clouds, dimensioned floor plans with sections and elevations, terrain rasters, change maps, meshes and reports. It is made by Dr. Florent Poux at 3D Geodata Academy and runs entirely on your own computer.

There is no installer. Download the free build, unzip it and run n3d.exe: it is one self-contained Windows executable that needs no runtime or redistributable. To remove it, delete the file; its cache can be cleared first from Help > About Neurones 3D > Local index cache > Clear.

That blue prompt is Microsoft Defender SmartScreen. It appears for a new download that is not yet signed with a code-signing certificate and has no download history, and today’s Neurones 3D builds are not signed yet: publisher signing is being set up, and signed releases will open without the prompt. It is not a virus detection. Microsoft Defender Antivirus reports no threat in the current build (checked on the published zip). To run it, make sure you downloaded it from neurones3d.com, then choose More info and Run anyway. To be certain the file is the one we published, open PowerShell in the download folder and run Get-FileHash .\N3D-Free-0.34.2-win64.zip: it must print 05297c7bb79f6b0f2e7ded685c45f5eb75875c16ad3e425e8c7c322abc71606e. If Defender ever names a threat, do not run the file, and tell us.

Your own file, through File > Open… or by dropping it on the window. With no data to hand, File > Demo scenes generates six scenes on the spot (an indoor room, a terrain city, a powerline corridor, a streetscape, factory pipework and a sculpture mesh) and two pairs of clouds for comparison and transfer. The guided tour under Help > Guided tour walks through the interface in twelve steps.

No. N3D has no account, no cloud processing and no telemetry, and the licence is checked on your machine. The only things that go online are the ones you click: the links in the Help menu open this website in your browser.

File > Save Project (Ctrl+S) writes an .n3dproj beside your data: the labels, the camera, the measurements and the layers, not a copy of the points. File > Open Project… (Ctrl+O) brings the analysis back with its source data. Saving to a new location with Save Project As is a Pro feature, because a project carries the labels.

Yes. n3d-render-cli has more than thirty subcommands (render, floorplan, graph, ground, terrain, compare, transfer, primitives, report and others) and loads files through the same cache as the app, so a headless run and an interactive one see the same cloud. report exits with 0 on a pass and 2 on a fail, so a batch can sort results without reading documents. Each guide gives its command-line equivalent.

Viewing, importing, every process that runs in the viewer, and converting a file back out. That covers classification, segmentation, the ground filter, measurement, sections, meshing, the scene graph, the floor plan preview and change detection, with no trial clock and no account. The four trained classifiers ship in every build.

Writing out what the program worked out: computed columns (class, segment, confidence, height above ground, deviation) on an export, drawings (DXF, PDF, SVG), terrain rasters, GIS vectors, meshes as glTF, reports, region and zone CSVs, saved images and flythrough videos. Desktop, Engine & SDK and the academic licence unlock the same features in the program; Engine & SDK adds the Python package and the command line. The boundary is enforced in code and tested in both directions.

Help > Enter License…, paste the key (it starts N3D-) and press Activate. The key is stored in %APPDATA%\n3d\license.key and checked offline. It can also be supplied with the --license argument or the N3D_LICENSE environment variable, which is how the command line picks it up.

Never. A key is an Ed25519 signature checked on your machine, with no activation server. The check is repeated whenever an export is asked for rather than remembered, and costs about 26 microseconds.

It is not a subscription. Every paid edition is one payment for an offline key that does not expire, and renewing is optional. The pricing page lists the editions and their prices. Purchasing opens at launch; until then the free Viewer is the complete program without exports.

A key covers every build released in the twelve months after you buy: at least four releases, because a new build ships every quarter. Those builds keep working for good. The key is checked against the release date of the build, not against today’s date, so there is nothing to expire, nothing to reactivate and no server to lose. The Founder’s edition is the same licence at the launch price: the first 200 licences, or 60 days after launch, whichever comes first.

Nothing breaks. Every build released in your twelve months keeps working. Newer builds need a renewal, which is optional and costs 20 % of the edition’s price for another twelve months of builds.

Desktop: one named person, on all of that person’s own machines. Engine & SDK: one developer, plus the Python package and the command line on as many machines as your organisation runs for its own work, servers and CI included, but not as a service for others. Academic: one student or researcher; a lab buys one per person. Five seats cost the price of four.

It is the engine in your Python: pip install neurones3d, with numpy in and numpy out, reading LAS, LAZ, E57 and PLY without a copy, opening clouds larger than your memory, and running the same segmentation, classification, ground filter, terrain, change detection and floor plans as the program. With it come the notebooks, the headless command line n3d-render-cli, the Desktop edition, and the academy’s Write the Tool course line. One developer, and the machines of one organisation. You may not pass the package or your key outside it, or run it as a service for third parties; putting the engine inside a product you sell needs a written agreement first. The Rust source is not included: it comes only under a separate written agreement.

Yes. A Desktop owner upgrades by paying the difference between the two prices, at the prices in force when they upgrade.

It is one price for everyone in teaching and research: €199 per person, for the Desktop edition, for non-commercial work only, on proof of enrolment or of a research post. A lab or department buys one per person, on invoice or purchase order. Publications that use N3D should cite it. Commercial work, including contract research for a client, needs Desktop or Engine & SDK, and so does the Python package.

Yes. Institutes and organisations can ask for a quote at howto@learngeodata.eu, send a purchase order and pay the invoice by bank transfer. Every card order gets an invoice too, issued by 3D Geodata Academy.

Without. Prices are one-time and exclude VAT, which is added at checkout where it is due, and the total is shown before you pay. A business in the European Union with a valid VAT number is invoiced without VAT, under the reverse charge.

The key is delivered by email as soon as you pay, so at checkout you ask for immediate delivery and acknowledge that you lose the fourteen-day right of withdrawal: purchases are final. Your legal guarantee of conformity is not affected. That is why the free Viewer is the complete program without exports: try it on your own data first. The terms give the details, including how to withdraw if delivery had not started.

Yes. neurones3d needs an Engine & SDK key, which it finds in the N3D_LICENSE environment variable or in the same key file the program uses, so one activation serves the program, the command line and Python. Ask for a 30-day trial key if you want to try it on your own data first. A Desktop or academic key does not unlock Python.

The same for everyone, and it runs on feedback: one feedback form, a public board to vote on what comes next, the guides and the FAQ, and at least four releases a year, planned from what users send. There is no service-level agreement and no phone line.

Point clouds: LAS (PDRF 0 to 10), LAZ, COPC, E57 (multi-scan, with panoramas), PLY, PCD, NPY and ASCII .xyz .pts .asc .txt .csv, whose column layout is detected from the values. Splats: PLY and SPZ. Models: IFC (2x3 and 4), STEP (AP203, AP214), USD (.usd .usda .usdc .usdz), glTF / GLB, OBJ and STL. Drawings: GeoJSON, Shapefile, DXF, SVG and CityGML. The format matrix gives what each one carries and how fast it opens.

Point clouds as PLY, LAS and CSV, a USD stage (.usda) or a self-contained web viewer. Meshes and voxels as glTF / GLB. Drawings as SVG, DXF (R2000) and PDF 1.4. Vectors as GeoJSON and Shapefile. Rasters as GeoTIFF and ESRI ASCII grid. Reports as HTML. Images as PNG or JPEG and flythroughs as MP4. Writing results out is a Pro feature.

No. DWG and DGN are proprietary binary formats: DWG’s specification is not published, and the only maintained open reader is LGPL, which N3D’s permissive-only licence policy excludes. So neither is read nor written, and N3D says so. Save the drawing as DXF from the program that made it, or convert a folder with the free ODA File Converter; N3D reads DXF fully and writes drawings as DXF R2000 (which AutoCAD and every CAD package open), PDF and SVG.

The class column fills LAS’s classification byte (0 to 255). Segment, instance and component ids are written as exact 32-bit unsigned extra bytes, and computed scalars such as height above ground or deviation as 32-bit floats, so PDAL, laspy and CloudCompare read them back. Intensity, returns, point source and scan angle keep their standard slots. The file is LAS 1.2 unless a class exceeds 31 or a coordinate system is present, in which case it is LAS 1.4.

Yes. It is read from LAS GeoTIFF keys, the OGC WKT record and LAS 1.4 extended records, carried into reports, and stamped on a LAS export as long as the geometry is still the source’s. A cloud that was moved by hand is written without it, because the stamp would no longer be true. Vector layers are checked against it and a clash is reported.

N3D says so. A half-finished download keeps a plausible header, so most readers do not notice; N3D checks the LAS 1.4 record offsets against the file size before decompressing anything. A damaged USD stage is refused before anything is allocated from a count inside it.

Four, in every build including the free one. Indoor, ten classes: 81.9 % and 82.3 % held-out accuracy. Outdoor (LiDAR), aerial land cover: 86.2 %. Powerlines: 87 to 88 %. Streetscape, fifteen classes of street furniture: 31 of 32 traffic-sign objects found. Accuracy is per point, on data the model was not trained on.

Each classification writes a confidence column: the share of the random forest’s trees that agreed. Colour by it to see where the model hesitated, threshold on it, and review those parts in Label Components…. N3D does not certify its own output; confidence, a human override and a baseline you can export are what it offers instead.

Against IGN LiDAR HD’s own production ground class on 16.2 million points, at a 2 m resolution and a 0.5 m threshold: precision 83.8 %, recall 97.9 %, F1 90.3 %, in 2.1 s. It needs no training data and no model file. Precision and recall are reported separately because they fail in opposite directions.

Not inside the app. You can correct labels in Label Components…, keep a baseline to compare the model against your review, and export per-segment features with n3d-render-cli classify-features (Pro) to train elsewhere.

It is closed, not edge-manifold, and N3D says so. Dual contouring puts one vertex per cell, and where two sheets of surface pass through one cell that vertex serves both: measured at 501 non-manifold edges on a 20,000-point sphere and 2,431 on a real indoor scan. The mesh audit reports boundary edges, non-manifold edges, shells and genus.

With M3C2 and a level of detection. Both surveys are averaged in a cylinder along the local normal, and each point carries the 95 % change it would take to be believed. A region with no points in the later survey is reported as not observed, not as lost, so a parked van is not called a demolition. On the demo pair a 120 mm settlement is found and a 10 mm one is reported unchanged against a measured 14.9 mm threshold.

The limit is the disk, not the memory. The index is built out of core with bounded RAM and memory-mapped back: 43.5 million points open in about 1.2 s, and a 127.8 million point, 7.9 GB E57 in about 22 s. Very large clouds are classified in tiles automatically.

Yes. Process > Floor plan… builds the scene graph, finds the rooms by flooding the empty space, extracts the walls between their measured faces with their openings, and draws a dimensioned plan with room areas, a scale bar, a north arrow and a title block, plus sections and elevations placed where they show the most. On a 43 million point survey the whole set takes about a second. Nothing needs tracing by hand.

No. The plan is drawn from the points, so any cloud N3D can open works: LAS, LAZ, E57, PLY and the rest, from a terrestrial, mobile or handheld scanner. No trajectory, no panoramas and no upload are needed. An IFC model can be drawn too, from its own storeys, rooms and walls.

A plan per storey, and automatic sections and elevations, at a scale from the ISO 5455 series (1:20 to 1:1000 when fitted to the sheet; 1:20 to 1:500 when set by hand) on A4 to A0. Each is saved as SVG (text stays text), DXF R2000 (model space in metres at 1:1, with real dimension entities) and PDF (vector, at the sheet’s true size). The building is also written as GeoJSON and Shapefile. Saving is Pro; the preview is free.

Lettering from the ISO 3098 series only (1.8, 2.5, 3.5 and 5.0 mm), scales from ISO 5455, a sheet frame with a 20 mm filing edge per ISO 5457, a title block with size, sheet and revision per ISO 7200, pen widths and hatched poché per ISO 128, dimension text above the line as read per ISO 129, and ISO 13567 layer names in the DXF.

Yes. Drag a dimension, a room label or a mark to move it: a dimension slides along its normal and its witness lines stay on what it measures, a room label stays inside its room, and the scale bar, legend and north arrow move anywhere clear above the title block. ✚ note adds a note with a leader that snaps to a wall; a right-click resets a moved item. Further editing belongs in CAD, which is what the DXF is for.

Wall thickness is as good as the decomposition voxel: about plus or minus 30 mm at the default 50 mm voxel on a real survey, exact on a synthetic test. Ends are joined within 0.9 m and a wall running into another’s side within 2.2 m; wider gaps are left as the survey found them rather than bridged on a guess. Levels are on the scan’s datum.

A 64-bit Windows 10 or 11 PC with a GPU that supports DirectX 12 or Vulkan. Integrated graphics work: they start in the Eco quality preset, which drops supersampling and effects for smoothness. See system requirements.

Less than the file size. Point clouds are indexed out of core and streamed, so a cloud larger than your RAM still opens. Composing a large USD stage for the first time is the heaviest case measured: 6.5 GB peak for a 900,000-prim stage, after which every reopen reads a cache in 1.64 s.

Not today. N3D is Windows only; a macOS build is on the roadmap.

No. The classifiers, segmentation, decomposition and the ground filter run on the CPU, on your machine. The GPU draws the scene.

In a local cache folder, never beside your data, so cloud-synced folders such as OneDrive are not filled with index files. Help > About Neurones 3D shows its size and clears it; the next open rebuilds what it needs.

No. Files are opened, processed and written locally. N3D has no upload, no cloud service and no account.

No. There is no analytics, no crash upload and no usage reporting in the application.

Nothing by itself. Help > Send Feedback… puts your message, the version, the build and the machine type on the clipboard (no file names, no data), and Open the form… opens the contact section so you can paste it.

Three strictly necessary items and nothing else: the n3d_board voting cookie on the board, a draft of the feedback form in local storage, and your cookie choice. There is no analytics and no advertising, and a Global Privacy Control signal is honoured. Cookie settings in every footer shows the list.

No. There is no mesh decimation, and OBJ is read-only. Meshes are written as glTF / GLB.

No. Manifold repair is not built. The mesh audit measures and reports the defect instead of claiming it away.

No. Trajectory and RTK pseudo-fix quality control is not built; it needs a trajectory parser per scanner manufacturer.

Not yet. The splat level-of-detail tree makes large captures fast (2.4 times faster at a 500,000-splat budget), but the whole tree is uploaded to the GPU. Point clouds, by contrast, stream beyond video memory already.

No. Automatic metric anchoring needs a seven-parameter solve that is not built. A capture can be rescaled by hand in the layer’s Reposition window.

No, deliberately. N3D reports a per-point confidence, lets a person review and correct every component, and keeps the model’s baseline beside the human labels. That is what can be signed; a model marking its own work is not.