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Control LAZ tile size

Since the last update of Pix4D it seems the LAZ output tile size has gotten larger - so large in fact that its causing problems with other software. Is there a way to control the tile size? Has anyone else run into this?

I am having similar issue.  las file has too many points for a direct import to Civil 3D.  I believe it has to stay below 10million points.  I would like to have a clipping boundary to export the points I want/need.  I want the aerial photo for the whole site, but only need the points for about 1/4 of the site for volume calcs.  Anyone have a solution?

Todd,

Don’t even think of putting 10M points in Civil 3D. I have a powerful system and I won’t go over 50,000 (0.5% of what you want to do) not because the system can’t handle it but because the surface doesn’t look very good. Typically I keep my cloud sizes under 10,000 points.

LAStools works very well to get rid of redundant points and noise, but it’s a bear to get set up correctly and is quite expensive for a lone operator. Nonetheless I would recommend looking at it if you haven’t already. The problem is, you need to tile the point cloud down into small chunks and the current size produced by Pix4D is too big for the released version of the tiler. You have to contact the author directly to get a different version that works on a file stream and is much slower because the Pix4D clouds aren’t spatially sorted in a way that makes tiling fast.

I’m still experimenting with LAStools and haven’t purchased yet, so it will introduce some small errors and strip out data that is more useful to the Lidar folks. My current script to go from a Pix4D cloud to a cloud I will bring into Civil is 400+ lines long, so be prepared to invest some time.

For your current issue, perhaps you can use CloudCompare to import and clip the cloud. You can also clip small sections out and do easy editing and then recombine, export the Z ordinate to a scalar field so you color the points by height, run noise filters, etc. you should also use the classification functions in Pix4D and then export out only the ground points (use the Ray cloud editor layers tree for that).

Hope this helps.

Hi David.  Thanks for the feedback.  Most of that was over my head.  I am just starting to use point clouds.  I just did a 9.5million points file into Civil 3D today.  Civil 3D displays 150,000 of the points.  I create the surface from on the areas I need volumes on (gravel piles).  These are clean surfaces and the contouring looks great.  I wish Pix4D had an option to export only a specific area.  I believe there is a process using ReCap to delineate and use the area of interest.

Thanks! 

Then definitely download CloudCompare to clip your AOI. It’s free and will become indispensable.