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Author Topic: Dense point cloud: export point reconstruction quality parameter  (Read 8101 times)

RalfH

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At the moment, I am working a lot with dense point clouds. I'm still amazed by how - from nothing but a set of photographs - Photoscan can create and export dense point clouds with more than a 1000 million points without problems (yes, some patience is required). One thing I do with the dense 3D point clouds is, for example, to create 2D point density maps.

A feature that I think would be very useful would be an option to export a point reconstruction parameter as an additional column in the dense point cloud xyz file. That way I could also create maps showing the spatial distribution of point reconstruction quality.

P.S.: Of course, this feature would also allow to do point cloud filtering by reconstruction quality in post-processing.
« Last Edit: March 25, 2013, 11:09:23 PM by RalfH »

Diego

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Re: Dense point cloud: export point reconstruction quality parameter
« Reply #1 on: March 26, 2013, 01:17:16 AM »
Of course, this feature would also allow to do point cloud filtering by reconstruction quality in post-processing.

I think this does not add much, it is best to define the minimum number of images for the determination of a point, currently each point in the cloud of points is determined by a pair of images, why overlapping areas have a lot of points, but more is not always better. it would be more accurate if it is determined by three or more images, less points but more precision in the points. How it works Semi-Global Matching Intergraph and is much better. I've been compared with the algorithm of Intergraph and works excellent. For each point is determined by all possible images, and that gives greater precision, and the point cloud is thirty times smaller but much more accurate.

RalfH

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Re: Dense point cloud: export point reconstruction quality parameter
« Reply #2 on: March 26, 2013, 10:31:47 AM »
I am not talking about using a different 3D reconstruction algorithm.

I would like to have the possibility to export an additional data column with the dense point cloud which would contain information on reconstruction quality of each point. This could be the parameter "reconstruction error" or "reconstruction uncertainty" that you have under gradual selection in point cloud mode, or both of them. By the way, it is not quite clear to me what exactly these two parameter mean, so some more information from Agisoft would be great.

andyroo

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Re: Dense point cloud: export point reconstruction quality parameter
« Reply #3 on: July 09, 2013, 10:53:50 PM »
I would like to have the possibility to export an additional data column with the dense point cloud which would contain information on reconstruction quality of each point.

+1

I would love this. Even if the value was the number of images used to calculate the point location this would be helpful to remove erroneous points for me. The more I use dense point clouds, the more I think they are very powerful to deal with some of the artifacts I get from exporting DSMs in PS.