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DBH and height measurement

Added by Beyene Solomon Mulat over 2 years ago

Hi Jan
I managed extracting DBH and Height automatically using the new Beta 17 version. From your tutorial, you said the length column in the output excel table could be height and the height column could be a length. The result seems very nice. However, I have two issues to be solved.
1. So should I take the parameters column as you said?
2.I have tagged the trees with tree number in the plot before scanning each plot. So how can I much the tree dbh measured automatically with the manually measured dbh? Because I want to see how the dbh and height can be measured automatically and manually from each individual tree.

best regards
Solomon


Replies (4)

RE: DBH and height measurement - Added by Hackenberg Jan over 2 years ago

Hi Solomon

I am working on a bug with length. You should anyway use height. This is what you measure with a vertex on a standing tree. Height seems to be stable since a long time. So take height instead of length because it should not be buggy and is what you have measured if you did not fell the trees.

I just checked the whole file and it seems to be corrupt partially. Need more time...

The same file should have x,y positions inside the scan which you need to convert into real world stem positions. The solution you find in mathematics or statistics forum, not here. I will fix the x,y position though and try to fix length .... This is still a beta.

Thanks for your feedback.

Jan

RE: DBH and height measurement - Added by Hackenberg Jan over 2 years ago

Hi again

yesterday I fixed the plot level file (result_list.csv). Beta 24 (sorry for the frequent releases, Alexandre will release Computree 4 next week as far as I know and I need to be ready) will solve that issue.
The file will contain the following fields:
ID volume (m^3) length (m) height (m) DBH (cm) DBH_taper_linear (cm) cut_height (m) x_position y_position
volume is the sum of all cylinders volume, use only if you work under leaf of conditions and run the allometric improvement. My SimpleTree paper gives all needed details. Recommend for single tree scanning design.
length I do not recommend to use this, but it is interesting for foresters I assume. You have just height as GT comparison as soon as you use vertex and should use height instead.
height that one everybody who does not know better should use both height and length seem to be now reasonable close
DBH take this one, it is a direct radius from the DBH cylinder. If not stem cylinder exists at this height (should barely happen since yesterday use
DBH_taper_linear instead this one is an interpolated value
cut_height is not needed for people who do not do fency stuff in R
x_position + y position is what you need to link to GT measurements. You need to be able to transform scan coordinates with real world coordinates by your own. You find help in appropriate forums.

I just uploaded this version (Beta24) with an adapted script. Without warranty Alexandre will release next week Computree 4 including SimpleTree. I will only fix bug and not extend the pipeline after this release anymore.

Jan

RE: DBH and height measurement - Added by Landisch Patrick about 1 year ago

What step should one use to automatically determine a tree’s height? I have segmented individual trees within my scanned area and accurately extracted dbh, but am unsure of where the height can be calculated from. Thank you for any insight, I truly appreciate your software and dedication to maintaining it.

Patrick

RE: DBH and height measurement - Added by Hackenberg Jan about 1 year ago

Hi

you need to use the full QSM SimpleTree step to compute height. Well I assume that there is a faster step for only height (no QSM) from Alexandre aka ONF Plugin, but I am not sure.
Jan

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