POINT CLOUD
STREAM is a desktop LAS / LAZ viewer that opens large point clouds without uploading them anywhere. It streams the file in chunks, so a cloud far bigger than your memory still opens; then it turns the points into terrain you can work on — a bare-earth DEM from ground points, a surface model from all points, or an orthophoto from the point colours — and lets you measure volumes, cross-sections and slopes on the result.
A point cloud is a dense set of 3D points (x, y, z) captured by LiDAR or produced by photogrammetry. LAS is the standard format; LAZ is its compressed form, and STREAM opens both directly.
Point clouds are rich but heavy. To get engineering results you usually need to turn them into a surface — a DEM or a mesh — which is exactly what STREAM does on import.
One thing to be clear about, because the online viewers in this space do the opposite: STREAM does not draw the raw points. It rasterizes them into a surface and shows that. If you want to spin a cloud around point by point, a web viewer does it; if you want a terrain you can measure, that is what STREAM is for.
Both formats open directly — LAZ needs no unpacking. The importer streams the points through in fixed-size chunks rather than loading the whole cloud into memory, so file size is not the limit.
The import dialog reads the cloud first: point count, classification, RGB and bounds. If there are no ground-classified points, the bare-earth option is disabled and says why; if there is no colour, the orthophoto option is disabled and says why. Nothing is silently attempted.
Bare-earth DEM from class-2 ground points (minimum elevation per cell), an all-points surface model (maximum elevation per cell), and an orthophoto from the colour of the highest point. They are checkboxes, not a single choice — build the DEM and the orthophoto in one import.
The cell size is pre-filled from the cloud's point density, and the dialog previews the output size in pixels. Set it finer than the density and STREAM tells you that adds no detail — gaps are filled from neighbouring points, not new information.
The result is written in STREAM's native tiled format with overview levels, so the surface derived from a huge cloud opens and pans like any other DEM — only the visible tiles are resident.
The cloud is read and rasterized on your machine. Nothing is uploaded, which is the difference between a desktop viewer and the browser tools that ask you to drop your survey on their server.
Volumes, cross-sections, stockpiles, slope, hydrology, contours — every terrain tool in STREAM runs on the surface the cloud became.
Write the derived DEM out as GeoTIFF for the rest of your workflow, or draw on it and export vectors to DXF.
Select the LAS or LAZ file. STREAM probes it first — point count, classification, colour, bounds — and streams it rather than choking on the point count.
Tick the outputs you want: a bare-earth DEM from ground points, an all-points surface model, an orthophoto from the colours. Options the file cannot support are disabled with a note saying why.
The cell size is suggested from the point density and the output size is previewed. Change it if you need to; going finer than the density does not add detail.
The cloud is rasterized asynchronously into STREAM's native tiled format. A progress card shows the build and can be cancelled.
Inspect the derived surface in 2D and 3D and confirm the coordinate system before adding it to the project.
Run volumes, cross-sections, stockpiles, slope and hydrology on the surface derived from the cloud, and export the DEM as GeoTIFF or the vectors as DXF.
| Output | Built from | Available when |
|---|---|---|
| Bare-earth DEM | Ground-classified (class 2) points, the minimum elevation in each cell. | The cloud carries ground classification. If it does not, the option is disabled and the dialog says so. |
| All-points surface model | Every point, the maximum elevation in each cell — vegetation and structures included. | Always. This is the one output every cloud can produce. |
| Orthophoto | The colour of the highest point in each cell. | The cloud carries RGB. Without colour the option is disabled and the dialog says so. |
A LAS file is a point cloud from laser scanning or photogrammetry, and any point cloud viewer will open it. STREAM opens it for a different reason: not to spin it around, but to turn it into usable terrain — a bare-earth DEM from the ground points, a surface model from all of them, and then contours, volumes and cross-sections. LAZ is simply LAS compressed; it opens directly too, with no need to unpack it first.
No — it is a Windows desktop viewer, and that is the point. Online viewers ask you to upload the survey; STREAM reads it on your machine and nothing leaves it. It also handles clouds far larger than a browser tab will, because the file is streamed in chunks rather than loaded whole.
No. STREAM rasterizes the cloud into a surface — a DEM, a surface model or an orthophoto — and shows that. If you need to inspect single points, a point-cloud viewer built for that is the better tool; if you need a terrain you can measure and design on, that is what STREAM makes from the cloud.
Yes. STREAM opens both LAS and LAZ point clouds and rasterizes them into a DEM, a surface model or an orthophoto at the resolution you choose. LAZ is not unpacked first.
Yes, if the cloud carries ground classification: the bare-earth DEM uses the class-2 points and the minimum elevation per cell. If the file has no ground classification, STREAM disables that option and tells you — you can still build the all-points surface.
Start with the value STREAM suggests: it is computed from the cloud's point density, and the dialog previews the output size. A finer cell than the density does not add detail — the gaps are filled from neighbouring points — so it only makes the raster larger.
STREAM is designed for large clouds. The importer streams the points in fixed-size chunks instead of loading the whole file, and the result is written in STREAM's native tiled format, so the derived surface stays responsive however large the source was.
No. STREAM reads LAS and LAZ. RCP and RCS are proprietary scan project formats and E57 is not supported yet; export to LAS or LAZ from whichever package produced them.
Yes — that is what the import does. Choose the bare-earth DEM or the all-points surface, accept or change the resolution, and the LAZ becomes a DEM you can export as GeoTIFF.
If you only need to spin a LAS/LAZ file around, a free web viewer may be enough. STREAM is for when you need to turn that point cloud into a bare-earth DEM, a surface model, or an orthophoto — then measure volumes, cross-sections, and slopes on it, offline.
From the Download button on this site. It is a Windows installer (Windows 10/11, x64) and the same STREAM build for every feature — there is no separate viewer download. Once installed, opening LAS/LAZ files and everything you do with them works offline; nothing is uploaded.
For the terrain side of LiDAR work, yes: it opens LiDAR and photogrammetry LAS/LAZ, streams large files in chunks and turns them into a surface model, a bare-earth DEM (when the cloud is ground-classified) or an orthophoto that you measure and design on. It does not classify or edit individual points.
Free beta for Windows x64. Works fully offline with GeoTIFF, LAS/LAZ and DXF.
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