[chestnut sugar GIS] how does global mapper batch produce ground contour lines through DSM

【 Chestnut sugar GIS】global mapper How to use dsm Mass production of contour lines and elevation points

Operation steps

Catalog

1. Prepare the data

2. dsm Convert to las

3. las Automatic classification

4. After classification, only ground points are reserved

5. Yes las Conduct thinning

6. Generate contour lines directly

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1. Prepare the data

need dsm, Contains information about the surface elevation

2. dsm Convert to las

3. las Automatic classification

Automatic classification requires a moment

4. After classification, only ground points are reserved

Right click the results generated by classification - analysis - grid - from 3D vector /Lidar Data to create elevation grid

  Click the position in the red box to filter the point cloud

Check only the ground points

 

  The data before filtering is shown in the following figure ：（ Grayish brown is due to the use of classification rendering ）

The filtered data is shown in the following figure ：

4. Fix the model

Fill in the remaining vacancies

export las data

Also right click on the layer -

5. Yes las Conduct thinning

Load the newly generated point cloud , Because the dot density is too high , Use thinning

Set the thinning spacing

Before thinning, see the figure below ：

  After thinning, see the following figure ：

 

6. Generate contour lines directly

 

Export contour lines dwg Format

Right click on the contour layer -

 

  stay cass As shown in the figure below ：