Isoline Extraction
A contour is the set of locations where elevation equals a constant level.
Ch={(x,y): z(x,y)=h}
hk=h0+kΔh
Best used when: terrain needs line-based elevation representation.
Generate Contour
Generate vector contour lines from a continuous elevation raster at a chosen interval.
Terrain / ElevationEnd-User DocumentationTheory + Formula + Parameters1. What This Feature Does
Generate vector contour lines from a continuous elevation raster at a chosen interval.
Cloud workflow: choose data → configure the scientific method → run → review the resulting layer/report. No programming is required.
2. Recommended Workflow
Select elevation raster/band.
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Set contour interval and optional base level.
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Generate contours.
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Inspect line density and artifacts in flat/noisy terrain.
3. Theory, Methods & Equations
4. Input Data
| Input | Type | Requirement | Description |
|---|---|---|---|
| Elevation Raster | raster | Required |
5. Parameters Available in the Application
| Parameter | Default | Choices / Range | How to Use It |
|---|---|---|---|
| Band | 1 | 1 to — | |
| Contour Interval | — | 1e-07 to — | |
| Base Contour | 0 | — | |
| Minimum Vertices | 3 | 2 to — |
6. Output & Interpretation
The result should be interpreted according to the selected method and the physical meaning of the input data. Preserve source units, coordinate reference information, NoData meaning, acquisition date, and preprocessing level when comparing results.
Scientific interpretation: an algorithm can produce a numerically valid result even when the input data are unsuitable. Always check masks, units, sensor characteristics, spatial resolution and reference data.
Important: The contour interval should match DEM resolution and vertical accuracy. Very small intervals on noisy DEMs create clutter rather than useful information.
7. Best Practices
- Use analysis-ready inputs and remove invalid/cloud/noise artifacts that are not part of the target phenomenon.
- Choose parameters from the physical scale of the data, not only from visual appearance.
- Keep categorical and continuous rasters conceptually separate when selecting interpolation/resampling methods.
- Compare the result with the source image and independent reference information.
- Document the settings used when results will be compared across dates, sensors or study areas.