RMS

Any question about the main GUI application (frontend)
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aloe
Posts: 20
Joined: Fri Sep 16, 2016 11:21 am

RMS

Post by aloe »

HI
when i do registration or point alignment i get a RMS number and even when i do a cloud to cloud distance whats the difference between both?
the values are in what measurements is it mm ?
thanks
daniel
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Re: RMS

Post by daniel »

When doing alignment / registration, you get the RMS computed with the points actually used:
- a few of them for point-air based alignement
- a few thousands for ICP (depending on the 'random sampling limit' parameter)
- and all of them when computing the C2C distances

And the values are expressed in the same units as the input cloud (CC doesn't deal with units, it loads the point coordinates as they are stored in the input file).
Daniel, CloudCompare admin
aloe
Posts: 20
Joined: Fri Sep 16, 2016 11:21 am

Re: RMS

Post by aloe »

thank you so much for your reply and for the software as well.
I had customised a scalar field but most of the scalar field was grey? whats does this mean? and when i want to have a symmetrical scalar field it doesn't get applied on the data?

thanks a lot
daniel
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Posts: 7711
Joined: Wed Oct 13, 2010 7:34 am
Location: Grenoble, France
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Re: RMS

Post by daniel »

With a custom color ramp, you can't use the 'symmetrical' option (you simply have to define the color ramp in a symmetrical way).

And all gray points correspond to values outside the defined ramp range.
Daniel, CloudCompare admin
aloe
Posts: 20
Joined: Fri Sep 16, 2016 11:21 am

Re: RMS

Post by aloe »

hi there
when i do alignment for my stl files from a scanner, do i have to sample both scans to align them over each other to check deviation ? or only the model i want to compare the reference to ( a reference which is also scanned and saved as STL).
and when i want to sample based on what i select the number of points?

THANKS ALOT
daniel
Site Admin
Posts: 7711
Joined: Wed Oct 13, 2010 7:34 am
Location: Grenoble, France
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Re: RMS

Post by daniel »

With the latest version (2.7 and 2.8 beta) you don't need to sample the reference mesh anymore.
Daniel, CloudCompare admin
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