Calculate plant height using dense cloud

[anagellerramser]

Hello Everyone,
I have flights of an experimental soybean area, two different flights on the same date, with a time resolution of 2 hours. One of the flights is before the plant sampling and the other is after. I generated two dense clouds and want to calculate the height between these two dense clouds, the height difference after the sampling in that specific point. What can I do to calculate this height? What tool should I use?

[daniel]

I would use the '2.5D Volume calculation' tool (see https://www.cloudcompare.org/doc/wiki/i ... .5D_Volume)

It converts the clouds to rasters, and then computes the difference between the 2 rasters. You can then export the raster difference as a (gridded) cloud. This should give rather robust distances, and you can read a specific distance by spawning a 2D label on a point of this grid (shift + left click on a point).

[anagellerramser]

Hi Daniel, thank you for your answer.

I used the volume tool, what generated a Height difference raster, that I can visualize as a cloud, and a volume. I transformed this cloud into a raster to import to QGIS and extract more information. I am not sure if I used the right parameters to generate both the cloud and the raster. Do you think I can use the volume that the volume tool calculates as the value that I need to find? (cloud after sampling - cloud before sampling)? My goal is to compare this value with field values.

Thank you for your help.

[anagellerramser]

I actually want to export the volume value, because I need to do this with 2,000 clouds, so I need a way to export this volume information to QGIS or excel

[daniel]

So the parameters you used seem ok to me. The volume should be reliable looking at the statistics displayed in the Volume calculation report (matching cells percentage and 'average neighbors per cell').

For the automation, you can use the command line mode (https://www.cloudcompare.org/doc/wiki/i ... _line_mode). The -VOLUME option generates the report in a 'VolumeCalculationReport.txt' file, so you'll have to add some intelligence to your script to extract the right piece of information from it before it's overwritten by the next call.

[anagellerramser]

Got it. Thank you for your answer.