Volume comparison between different projects of the same area

PIX4Dmapper PIX4Dmapper Questions/Troubleshooting
1

Hi,

I need to compare two different projects of the same area, surveyed in different periods. I’d like to know if there is a simple way to compare volumes in Pix4d (or using some other software), in order to know how much material has been added or removed.

Thank you

2

Hi Stefano!

The way to compare volumes in Pix4Dmapper is as it follows:

  1. Process your related projects separately with the same GCPs.
    If you do not have GCPs, you can mark some points in project 1 and take the coordinates that Pix4Dmapper calculates for these points. Then you should add as GCPs the same points in project 2 (using the coordinates that you already took from project 1). Then, the two projects will be perfectly aligned. The above-mentioned procedure is better explained here.
  2. Draw a volume object in Project 1.  How to draw a Volume
    Now you have the volume of this object/area in Project 1.
  3. Export the volume object.
    Right click on the volume object in the rayCloud > Export.
  4. Then open Project 2 and import the volume object.   How to import a Volume into Volumes.
    The idea of importing and exporting the base surface is to make the comparison accurate enough.
    Now you will have the volume of this object/area in Project 2.
  5. Compare your results by calculating the difference, e.g. in an Excel sheet. For more information see our article about Volume Difference of an Area Surveyed over different Time Periods.

Cheers! :wink:

3

Hi,

thank you so much for your help :slight_smile:

4

You’re welcome! 

Have fun exploring the software :wink: