Turning on Shape From Silhouette Crashes Zephyr Pro

[Modeler17]

Hi All,

I have been working with Zephyr Pro making full body scans. I had a subject which I thought might benefit from using Shape from Silhouette for stereo Initialization. But when I enable Shape from Silhouette on the stereo setting page and then begin the point cloud densification, Zephyr immediately crashes.
This happens whether I choose the ON option or the USE FOR STEREO INITIALIZATION Option.
Other settings are as follows:
Output type = Refined
Resolution = 75%
Noise Filtering = 29% (set high to filter out noise under armpits)
Depth Map Hierarchical levels = 1
Discretization Level = Very High
Voting Type = Heirarchical
Looseness = 0
Has anyone else experienced this?

[Andrea Alessi]

Hi!

As a quick test, may I ask you to try and reset Zephyr to factory settings ? We did not change anything in the SfS algorithm in 3.1x, so i suspect that the problem might be tied to some setting somewhere (you can do it from tools -] application -] restore factory default settings )

I will do some testing right away to see if i can reproduce it!

[Modeler17]

Hi Andrea,
I did the reset. Then I tried to run dense point cloud generation with the silhouette turned on. I got the same result, crash.
I hope you can reproduce the error at this point.

[Andrea Alessi]

Hm, i couldn't reproduce it this morning

Any chance you could share with me the dataset ?

[Modeler17]

I have a couple of thoughts.
I am trying to activate the silhouette feature when densifying a merged project. When I tried to activate the silhouette feature on an unmerged project, I simply got an alert that the densification failed.

So perhaps I am dealing with two issues:
1) The crash is happening because I amd trying to silhouette a merged project?
2) perhaps, because of the arms overlapping the body at points, it is not a suitable project for merge anyway?

I will check with my subject to see if it is OK to send you the project files if you think this would help.

[Modeler17]

Point 2) correction. I meant to say "perhaps, because of the arms overlapping the body at points, it is not a suitable project for SILHOUETTE anyway?"

[Andrea Alessi]

The arms overlapping the body is not a problem for the SfS itself. The SfS will discard automatically cameras with partial views (the silhoutte must be of the whole subject).

It is possibile, however, that there is a bug when dealing with merged dense point clouds then, i tried simple datasets earlier today so that's something different for sure

[Modeler17]

Ok, so as soon as I get permission from my subject, I will upload the merged project file and possibly one of the original unmerged project files (for comparison). I will send you an email once the upload is completed.

Thank you!

[Andrea Alessi]

Thanks!

If you need a signed NDA anyways (for this or for future uploads) feel free to ask

[Roberto]

Hello!

I've had a look at your latest dump file that you sent us and maybe I've understood the problem. The generated point cloud has zero points after the shape from silhouette and it was crashing after the shape from silhouette. We will fix the crash of course, but still there's the problem of the zero points / failed processing.
Maybe the bounding box has been not set properly after the merge? Or some camera are not correctly oriented? Can you please try to reset the bounding box (right click on the sparse point cloud -] adapt bounding box to points) or increase the looseness factor?

[Andrea Alessi]

I can confirm what Roberto said. There's a bug, which is now fixed in our internal build. Expect a bugfix in the next release, scheduled for next week! Thanks for reporting!

[Modeler17]

Oh, great news! and you are welcome. I really appreciate Zephyr Pro. It is very useful