Quality of mesh output

Hi There

I am really struggling to get quality/acceptable results when generating the 3D mesh.

I’ve spent a fair amount of time adding surfaces, reoptimising and cleaning up the densified cloud (which looks great and the Orthomosaic is spot on for this test dataset, A single double grid flight, GSD 0.98cm). This doesn’t appear to help the mesh output, if anything it seems worse! Ive spent hours on the support site, trying things out but to no avail.

its a simple building in progress (with a lot of clutter) plenty of visual interest

Im also struggling with this post as I don’t wish it to be a ‘versus’ post but as an experiment I uploaded the raw dataset to Drone Deploy as a check, so no MTP’s, surfaces etc.

The results were significantly better, the Drone Deploy mesh was denser, had detail where it should and dealt with things like clutter and thin items such as scaffold more ‘elegantly’ (flattened spurious bits and pieces etc), textures were handled better in places with less smearing. Better so much so that I was bit taken aback. I would love to be able to get these results (or better) in the Mapper. I don’t like DD because there is no control, its fire and forget stuff, but ‘out of the box’ results (in terms of the mesh generation) is pretty good. Look at the definition of the dormers and the truck, detail on the round window.

below are comparison screenshots.

If anyone could help or at show me what I’m doing wrong (I’d really like to be doing something wrong!)

 

Pix4D version

Drone Deploy version (unsure why they are a bit dark, didnt appear like that in app)

 

 

 

 

 

I hate to say this here but Pix4D is not great at making a mesh…it is the best at accurate point clouds but something like RealityCapture is much better for a mesh.  I have spent weeks and weeks trying to improve Pix4D’s meshes and it just never has worked for me.

For my company, we don’t mesh in Pix4D…maybe some day they will get meshes improved but it is only eye candy as the “real data” is in the point cloud.

Thanks Adam, that’s a shame, I agree its only eye candy but I have some customers that like the visual of a mesh and animated orbit.

At least it wasn’t me so much. 

Well hopefully some others here have some better suggestions but I strongly recommend checking out RealityCapture from CapturingReality.com

And I know very well that people like to look at the mesh…point clouds are not easy to visualize :slight_smile:

indeed, currently checking out. cheers

I wanted to show everybody (including Pix4D) that one piece of software doesn’t fit every need.  Here is a Pix4D cloud mesh followed by a RealityCapture mesh of the exact same pictures…both pieces of software fully customized to do their best.

Hello Rob and Adam,

This is a very interesting discussion. Here at Pix4D, we are very interested in taking steps to improve the mesh generation, both in terms of speed and quality. Already, version 4.0 is much faster for the regular mesh and particularly the LoD generation.

Regarding the quality of the mesh, there is space for improvement, as shown by your screenshots, and we do have some ideas on how to improve the outputs. At the same time, it is hard to compare meshes that might be of different number of triangles or texture size and reach a safe conclusion. It would be very interesting for us to compare the two point clouds and meshes (and their texture) to reach safer conclusions. We would really appreciate it if you could share these files with us (together with the p4d project and images) so as to help us improve our mesh export. You can do so by sharing a google drive or wetransfer link in this post or by sending a support ticket here.

As a last note, looking at the screenshots of the rayCloud, it seems that some of the surfaces drawn in the rayCloud do not have the correct orientation (drawn counterclockwise); in this case, please make sure that the option Automatic Orientation and Use for DSM and Triangle Mesh are selected for all the surfaces drawn to improve the mesh. If the option Automatic Orientation did not provide the expected results, you can try to disable the option making sure that the surfaces are drawn counterclockwise. You can find more information here.

Thank you for your collaboration.

Best regards,

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Hello Despina Karavia,

Architect designers are rejecting our 3D meshes results. Not only Pix4D meshes but coming from any photogrammetry method. This is not about precision or resolution but only based on esthetics.

The problem is the low quality and high number of triangles. Low quality refers to topological artifacts on the meshes.

Trying to improve results on Meshlab I’ve seen a tutorial related to topological artifacts. They say that it often comes from mesh simplification. As Pix4D outputs refer to simplified mesh, I’m wondering if this precisely is a point to improve.

Workarounds exist but increasing cost. I perfectly agree with the fact that one software cannot do everything or solve all existing cases.

Best regards

Daniel, other software as I mentioned does meshing better. Pix4D is best for the point cloud.

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