Keeping Grid info (e57)

[jonathanlepage]

Hi,

Using the command line utility, is there a way to keep an E57 gridded after manipulations?

here's the context :

We have Large point clouds (20-50gb) that we clean with an in-house decimation tool to reduce the size without loosing quality of the data (down to 4-10gb).

To clean outliers and noise (from steam and snow) I use a density filter but my output looses all grid information.

here's my command line.
cloudcompare -NO_TIMESTAMP -C_EXPORT_FMT E57 -AUTO_SAVE OFF -o %FILE% -DENSITY 0.01 -TYPE KNN -FILTER_SF 10 MAX -MERGE_CLOUDS -SAVE_CLOUDS

Thanks,

[daniel]

For now CloudCompare doesn't handle "gridded/structured" clouds (it considers all clouds as "unstructured"). Blame the manufacturers who were jealously keeping their formats description for themselves and were only exporting plain ASCII files ;)

There's a project to add a 'structured' cloud structure in CC but I fear it will take ages before this work is actually achieved.

Meanwhile there would the possibility to "remember" that the cloud was structured (basically saving the grid dimension and angular steps as "meta-data") and then projecting the points back to their 'original' 2D scan world when exporting as E57 (or PTX).

[jonathanlepage]

Meanwhile there would the possibility to "remember" that the cloud was structured (basically saving the grid dimension and angular steps as "meta-data") and then projecting the points back to their 'original' 2D scan world when exporting as E57 (or PTX).

I was thinking of using that method with the e57xmldump utility from lastools wich creates the meta data of the e57 in XML format.

I just wouldn't know how to write it to the e57 so it would "keep" its structure.

any suggestion?

[daniel]

The main issue is that CC actually writes the points as an "unstructured" set (and not a gridded one). So in addition to be able to restore the original meta-data, you would still need to back-project the points in their original grid inside CC.

And doing this in the current state of CC would be an horrible hack (the kind of hack that one can do by modifying the sources and compiling CC on his machine, not the kind of one I can do ;)

[jonathanlepage]

Allright, I'll try and find another way to do it.

Merci de prendre le temps de répondre à mes questions.

[Laserbrain]

Hi,

Old topic. Wondering if CC is able to output structured data in the newest release, or if there are any future plans for it?

Thanks