This tutorial illustrates how to perform different types of measurements based on the Digital Elevation Model for the projects covering mining or construction sites. If you need guidance on how to build DEM with Metashape refer to Tutorials. This workflow is suitable for the Metashape Professional version.

Build DEM using the following settings:

  • Surface data: Point Cloud
  • Interpolation: Enabled or Extrapolated.

To switch to the Ortho view mode double-click on DEM or Orthomosaic label in Workspace pane: 




Contents of this article:




Measure point coordinates 


1. Switch to the point drawing tool. Using the corresponding button on the Toolbar.


2. Create the item in the point of interest on the Ortho view and choose Measure option from the context menu after right-clicking on the point:



3.  In the opened dialog on the Planar tab three-dimensional coordinates for the selected point shape will be displayed. Using Save button the report data can be saved to PDF and HTML format.




Measure distances and profiles


1. Switch to the polyline drawing using the corresponding button on the Toolbar


2. Draw a polyline from one or more segments and choose Measure option from the context menu after right-clicking on the polyline: 




3. In the opened dialog on Planar tab the coordinates of the polyline vertices will be displayed and the planar length (in XY plane) of the polyline will be displayed in Perimeter field


4. In Profile tab the profile information along the polyline will be displayed. Moving the mouse over the profile will display the height information for the actual point. The Length field contains information about the length of the profile. Using Save button the profile data can be saved to KML, SHP, DXF vector formats and in JPEG, JPEG 2000, PNG, TIFF, BMP, OpenEXR, TARGA raster formats.

 


5. You can Generate Shape Report. Using Save button the report data can be saved to PDF and HTML formats.



The report includes image with shapes, elevation mode, and table with shape parameters, such as perimeter.


Measure volume


1. Switch to the polygon drawing tool using the corresponding button on the Toolbar.


2. Draw a polygon using three or more vertices and choose Measure option from the context menu after right-clicking on the polygon: 




3. In the opened dialog on the Planar tab, the coordinates of the polygon vertices will be displayed. The length of the polygon perimeter (in XY plane) and the area covered by the polygon in XY plane will be displayed in the Perimeter and Area fields correspondingly: 



4. In the Profile tab, the profile information along the polygon perimeter will be displayed. Moving the mouse over the profile will display the height information for the actual point. The Length field contains information about the length of the profile. Using Save button the profile data can be saved to KML, SHP, DXF vector formats and JPEG, JPEG 2000, PNG, TIFF, BMP, OpenEXR, TARGA raster formats.



5. In the Volume tab, the volume measurements are displayed. 

  • You can select one of the three supported options for the volume calculation: Best Fit, Mean level or Custom level plane. 
  • Best fit and Mean level planes are calculated based on the drawn polygon vertices. Volume measured against custom level plane allows to trace volume against the fixed value that can be defined by the user. 
  • Volume measurement fields contain information about the volume above the selected plane, below it, and total volume. 



Best fit and mean level planes are calculated based on the altitudes of the bounding polygon vertices. Volume measured against custom level plane allows tracing volume changes for the same area in the course of time. The Level is set by the user in the corresponding box. Update button should be pressed for the Volume to be re-calculated against the set level.

Volume is calculated Above set level and Below set level, also Total volume value is calculated according to the following formula: Total volume = Volume above - absolute value of the Volume below


6. Using Save button the report data can be saved to PDF and HTML formats. The Report includes image with shapes, elevation model and table with shapes parameters such as perimeter, area, volume (above, below, total). 


Export shapes


To save the shapes, right-click on the label of the Shape Layer to be exported in the Workspace pane and choose Export Shapes to option from the context menu. File data can be saved to SHP, KML, KMZ, DXF formats.