Scanner app photo stitching and ridge artifact


#1

Hey all, I’m having a hard time understanding how the image mapping works in the scanner app, since often the “color” display mode at the end causes warping and duplication in colored surface landmarks. Any idea on how to minimize this?

Also, a recent issue we’ve been having is with a ridge forming on the model when the most recent part of the capture connects back with the first part after a full revolution about the object being scanned. Re-calibration hasn’t seemed to help, and the only way I can minimize it is by moving the scanner very slowly, which results in even poorer recreation of 2D colored surface details (too may keyframes to be seamlessly stitched together?). Any insights you all might have on this would be invaluable!


#2

Could you, possibly, post a few screenshots of some of the scans you’ve taken for reference?

It seems that you are encountering a loop closure issues with both the color texture and 3D mesh.

I, also, want to let you know that the Scanner - Structure Sensor Sample Application is just a sample built to show off the features of the Structure SDK. It does lack robust features that can be seen in other apps.

Could you let us know a little more about your use-case so that we may suggest a more specific app for you to use?


#3

People never gave me trouble but I had trouble scanning large objects like cars and boats with Skanect. Its working better now though. When I could keep tracking I would get a disappointing closure overlap. I thought I was moving too fast or jerky movement. It turns out these objects are rather boring to the tracking algorithm.

I now attach several small cups or tape tags to the scan object to keep a solid track. Closures are much improved. You want contrast in geometry and color. It is also helpful to keep other objects nearby. Chairs and things in frame really help. These are very easy to edit it of a scan in meshmixer.

It would be helpful if the developers could add clear tracking quality indicators during the scans. We can try to keep several Xs on the screen to know things are going well. Right now it is just an error/freeze warning that you are either too fast or have few features.


#4

Hi Anthony,

Here are some screenshots of the two main issues I’m running into. Loop closure sounds like the right way to describe it, but I’m still not sure how to fix it.

Regarding our use-case, we hope to use the scans on torsos (with markers on significant landmarks, hence the stickers you see in the models) to run different volumetric analyses of growth over time. So far, I’ve encountered similar issues with Captevia.

Thanks so much in advance for your help!

Ridge2


#5

Hey Cheapscan,

You have a point there! Interesting that the more complex the room (ie more things in the frame) the better the scans seem to turn out. Will definitely explore options in that area!

Thanks so much.


#6

Couple of things.

The Scanner Application is a sample application used to show off our Structure SDK. I would recommend taking a look at other applications available for the Structure Sensor to see if you can get better results
You can find all apps available for the Structure Sensor by doing the following:

  • Connect the Structure Sensor to your supported iPad or iPhone
  • Navigate to Settings -> General -> About -> Structure Sensor -> Find App for Accessory

This will open the App Store, and display all apps available for the Structure Sensor and your mobile device.

Two, the results of a scan are affected by a number of different things. When scanning, try to limit the amount of natural IR light in the room by covering windows and doors. Also, try to increase the amount of artificial light on the object you are scanning to help reduce shadows. When scanning, try to limit going over areas multiple times by planning a scanning path before you start.

If you are still experiencing difficulty with your scans, posting a screen recording of the iOS device you are using while scanning would be very helpful.

Hope this information helps!