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Certification lab 4 - Don't see changes after removing noise/deleting objects

Good morning, all:

I am doing the Pix4D course, but in the LAB4, after removing noise by editting the point cloud, I generate a new mesh and see now changes, everything seems the same. I even run STEP 3, and the deleted points still appear. I have tried a lot of times changing the processing options, but I get nothing. I’m a little bit desperated. 

Thanks for your help

Hi Jose, 

Which version of the software do you use? I will try to reproduce the same behavior. 

When regenerating the 3D Textured Mesh, do you use Process > Generate 3D Textured Mesh or do you recompte step 2 entirely?

If possible, please share the log file of your project and the quality report with a file sharing service. This will enable me to investigate more in detail. 

Thanks!

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Hi, Pierangelo, thanks for the quick answer.

Version 4.0.25

I have tried both ways. In fact, I don’t know what should I expect. For example, LAB 4 says “Go back to the rayCloud view and add planar surfaces on the side of the sheds and regenerate the mesh. Do you see any improvements”. I do that, but I don’t see any change after regenerating the mesh, I see the green rectangle that I have created (that was there before regenerating the mesh), and nothing more. I would expect to see a new surface or something similar.

If I unmark the “deleted” group, all the cars appear again (that also happened before regenerating the mesh) so, what is the practical change that regenerating the mesh produces?

 

And some “ghost” points remain even when the group “deleted” is unmarked. But they seemed totally gone before regenerating the mesh:

How could I share the log file with you?

After processing step 3, the removed points are gone in the DSM, that does work at least.

I will be doing my Pix4D certification exam tomorrow, without possible delay.

Thanks again!

 

 

Okay, let me answer each question individually below: 

1) Surfaces to improve 3D Textured Mesh

Please make sure to select the checkbox Use for DSM and Triangle Mesh in the surface options. The detailed procedure is described in this article. If this is selected and the surface is well aligned to the wall, it should flatten the area in the 3D Textured Mesh.

2) Deleted points

As long as the points are assigned to the Deleted class they should not be taken into account when the 3D Textured Mesh is regenerated. The checkbox you have checked in your screenshots is only for visualization purposes, by default the Deleted class is not displayed. 

3) Ghosts points - Automatic Tie Points


The points you see are the Automatic Tie Points (ATPs) that were generated after step 1. Initial Processing. If you unselect the checkbox next to “Automaticos” in your screenshot, these will not be visible anymore. 

I believe I do not need to see the log file for the moment, as I believe the questions could be answered without. In case you would need to send the log file once, you could use a service such as Google Drive, Dropbox or WeTransfer to send the log file. 

Good luck for the certification exam!

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Hello, Pierangelo:

Question 1) Check.

Question 2) Check.

Question 3) Check.

Your explanations help me a lot and I see things clearer now. I hope it will be enough. 

Thank you very much from my heart for your help, and I will let you know if I pass.

Best regards!

Hello Jose, 

I’m happy that it helped you! Yes, let me know :slight_smile:

Kind regards!

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Hi, Pierangelo, 

I passed!

Thank you very much!!!

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Yeah! Congratulations!