select / delete points by color

[patman27]

Hello,

is it possible to select and delete points with a specific color, e.g. if you want to erase all white points of your point cloud?

Thanks,
Patrick

[daniel]

You can convert RGB colors to one or several scalar fields (with Edit > Colors > Convert to SF). You can choose to export each component (R, G, or B) or the mean value ((R+G+B)/3) as a separate scalar field.

Then you'll be able to segment the points based on the SF values (Edit > Scalar fields > Filter by value). If you only want to remove white points, you can directly work with the composite SF.

[patman27]

Ok thank you this solves my problem :)

[Matthieu]

thank you a lot daniel,
it solves my problem :)

[jochemla]

Hi daniel,

What if I would like to select green points RGB = (0, 255, 0) ?
The ideal would be to allow setting a custom scalar field from RGB values. For example, I could set X = 2^16 x R + 2^8 x G + B and find points where X=000000001111111100000000 in binary.

Would that be possible ?

Thanks a lot,

Jonathan

[daniel]

Oups this message was lost in the moderation queue :D.

For the records: https://github.com/cloudcompare/trunk/issues/363

[cosmocompare]

Hi, The option Edit>Colors>Convert to Scalar Field is greyed out and not selectable, it's for a RGB scalar field that was generated using Tools>Sandbox>Distance Map...

What is missing from the RGB distance map to let it be selectable by RGB values?

[daniel]

Make sure the map is selected (and the original cloud, as this one remains selected after the tool has finished).

[LeeFluff]

Edit> colours> Convert to scalar field
check boxes to enable all channels
Properties... Scalar Field Colours... scalar Fields dropdown active to select which channel

to get a specific R G B value.... you would have to first filter to the correct Red value...
Properties... SF Display Params ... Display Ranges... and use the sliders or enter number specifically

Edit> scalar fileds> filter by value, then Split

then change the scalar over to the next Green.... then filter...
and finally repeat for the last B field and filter.

This may be cumbersome... but if you actually know the RGB value in terms of 255:255:255, then you could do this.
you could probably use a tool like this to find the specific colour you intend to select for

https://www.ginifab.com/feeds/pms/color ... _image.php

[WargodHernandez]

We have the colorimetric segmenter for this now

colorPlugin.JPG (66.49 KiB) Viewed 13125 times

colorimetricSegmenter.JPG (80.98 KiB) Viewed 13125 times