Forum

Author Topic: Tie Points dense, but Point cloud very disappointing  (Read 2076 times)

rowild

  • Newbie
  • *
  • Posts: 26
    • View Profile
Tie Points dense, but Point cloud very disappointing
« on: October 07, 2024, 10:23:03 PM »
I recorded a spiraling ramp for bikers, leading up to a bridge, with a insta360 One RS. Usually 360 degree images and the Spherical setting in Metashape give supercool results. But this time I must have been doing something wrong. While the tie points are rather dense, the point cloud is very dissatisfying. I uploaded some image, which hopefully give some feedback and info (images were to large to be uploaded her to the forum):

Tie points:
https://dl.rowild.at/pcSpiralExampleImgs/tie-points.png

Tie points with Depth map infos:
https://dl.rowild.at/pcSpiralExampleImgs/tie-points-depth-map.png

The resulting point cloud:
https://dl.rowild.at/pcSpiralExampleImgs/pc-spiral-ramp.png

Excerpts from the console:
https://dl.rowild.at/pcSpiralExampleImgs/console.png

And here are also some of the images used:

https://dl.rowild.at/pcSpiralExampleImgs/0414.png
https://dl.rowild.at/pcSpiralExampleImgs/0649.png
https://dl.rowild.at/pcSpiralExampleImgs/0911.png
https://dl.rowild.at/pcSpiralExampleImgs/2486.png
https://dl.rowild.at/pcSpiralExampleImgs/3781.png
https://dl.rowild.at/pcSpiralExampleImgs/5594.png

I should mention that I tried with a set where every 30th, then every 24th, then 12th and eventually 7th image of a 30fps video was used. And I used "Spherical Camera". And i should probably also mention that the images, after the point cloud was calculated, are black+white when inspected, while the preview is in color. Here are 2 examples:

https://dl.rowild.at/pcSpiralExampleImgs/bw-img-1.png
https://dl.rowild.at/pcSpiralExampleImgs/bw-img-2.png

Any tips on how to improve the result?

olihar

  • Full Member
  • ***
  • Posts: 247
    • View Profile
Re: Tie Points dense, but Point cloud very disappointing
« Reply #1 on: October 08, 2024, 12:14:53 PM »

This data needs to be optimized and cleaned up for sure.

rowild

  • Newbie
  • *
  • Posts: 26
    • View Profile
Re: Tie Points dense, but Point cloud very disappointing
« Reply #2 on: October 08, 2024, 05:55:41 PM »
There are tons of tie points, so data is recognised I would assume. Don't understand why the point cloud is such a hotch-potch...

Alexey Pasumansky

  • Agisoft Technical Support
  • Hero Member
  • *****
  • Posts: 15118
    • View Profile
Re: Tie Points dense, but Point cloud very disappointing
« Reply #3 on: October 08, 2024, 07:15:25 PM »
Hello rowild,

Can you share the screenshot of tie points with the camera locations?

I would suggest the following changes in the process:
- disable reference preselection,
- lower tie point limit to 8000 - 10000 range values,
- try using Medium quality or even Low to see if the results are better.
Best regards,
Alexey Pasumansky,
Agisoft LLC

olihar

  • Full Member
  • ***
  • Posts: 247
    • View Profile
Re: Tie Points dense, but Point cloud very disappointing
« Reply #4 on: October 08, 2024, 07:30:17 PM »
There are tons of tie points, so data is recognised I would assume. Don't understand why the point cloud is such a hotch-potch...

Sure Tons of Tiepoints but it looks like a mess so I highly doubt its actually calibrated correctly.

rowild

  • Newbie
  • *
  • Posts: 26
    • View Profile
Re: Tie Points dense, but Point cloud very disappointing
« Reply #5 on: October 08, 2024, 07:37:40 PM »
Olihar - thank you for your answer(s), but you have a way of providing them that force me to keep asking. Why do you do that? It would be way more helpful and less time consuming, if you could share your complete thoughts and observations right away. Or not at all, which is ok.

What I need is help.
You are not providing it.

So I kindly ask you to please refrain from answers that do nothing else but force to post another question due to your answer.

IMO, it also wouldn't hurt anybody, if you could find a friendlier tone. Not only here.

Thank you!

olihar

  • Full Member
  • ***
  • Posts: 247
    • View Profile
Re: Tie Points dense, but Point cloud very disappointing
« Reply #6 on: October 08, 2024, 09:03:24 PM »

Again, I think its not calibrated correctly, what more do you want?

Badly calibrated data will give you bad or no output.

So I would suggest you have a closer look at the calibration you get, try filter it for example and see how it actually looks. Because right now it looks very poor and unusable.

How can we help, you provide almost no information other than this screenshot being the only one able to show your problem.

rowild

  • Newbie
  • *
  • Posts: 26
    • View Profile
Re: Tie Points dense, but Point cloud very disappointing
« Reply #7 on: October 08, 2024, 10:34:01 PM »
Thank you, Alexey Pasumansky, for your feedback and your advise! Making the camera visible in the point cloud was an important tip! It shows that on the second level of that spiral bridge something went wrong.

Here are 2 images of the object I filmes:
https://de.wikipedia.org/wiki/Praterbr%C3%BCcke#/media/Datei:Praterbr%C3%BCcke.jpg
https://www.derstandard.at/story/2000128494051/under-the-bridge

I am actually surprised that the internet does not offer better images of my motive, but anyway... in both pictures it is possible can see the "spiral" in the background, a bike lane that leads up to a bridge in order to cross the river.

The image of the tie points with the cameras visible is here:
https://dl.rowild.at/pcSpiralExampleImgs/tie-points-with-cameras.png

Being new to MetaShape, I don't know what it means when someone says "its not calibrated correctly". I used a insta360 RS One camera, and I am currently of the opinion that there is not much to calibrate, if it is the camera that is meant. Here is a screenshot of my camera settings anyway:
https://dl.rowild.at/pcSpiralExampleImgs/camera-calibration.png

Or what does "calibrating" actually mean, specifically in the context of this project?

(In my first post I linked over 10 images. Can they be opened?)

I will try some more renderings this night with the settings you recommend. Thanks again!

olihar

  • Full Member
  • ***
  • Posts: 247
    • View Profile
Re: Tie Points dense, but Point cloud very disappointing
« Reply #8 on: October 08, 2024, 10:45:49 PM »
Seeing your screenshot, I have to ask, what version/build number are you using.

rowild

  • Newbie
  • *
  • Posts: 26
    • View Profile
Re: Tie Points dense, but Point cloud very disappointing
« Reply #9 on: October 08, 2024, 11:08:32 PM »
The latest downloadable one.

olihar

  • Full Member
  • ***
  • Posts: 247
    • View Profile
Re: Tie Points dense, but Point cloud very disappointing
« Reply #10 on: October 09, 2024, 01:20:55 AM »
That does not answer the question. What version and build number. The reason I am asking is because of the screenshot of your software.
« Last Edit: October 09, 2024, 01:37:48 AM by olihar »

rowild

  • Newbie
  • *
  • Posts: 26
    • View Profile
Re: Tie Points dense, but Point cloud very disappointing
« Reply #11 on: October 09, 2024, 07:40:10 AM »
Olihar, you write: "That doesn't answer the question" – well, then you know what your answers feel like, when I read them.

"The reason I am asking is because of the screenshot of your software." – what has that to do with my problem? It doesn't explain anything. Aside from that, as for the version and build number everything should be mentioned in that very screenshot.

Alexey Pasumansky

  • Agisoft Technical Support
  • Hero Member
  • *****
  • Posts: 15118
    • View Profile
Re: Tie Points dense, but Point cloud very disappointing
« Reply #12 on: October 09, 2024, 07:43:43 PM »
Hello rowild,

Try to realign the images using the following parameters:

Accuracy - High
Key points per MPx - 2,000
Tie point limit - 10,000
Generic preselection - enabled
Reference preselection - disabled
Guided image matching - enabled
Exclude stationary points - enabled (providing that you do not have multiple images taken from the very same location).

In case there is a tripod visible or any considerable part with no data that is same on all the images, I would suggest to apply the same mask to all the images and enable Apply Masks to Keypoints option.

Also may be reasonable to update to 2.1.3 version, which is the latest release version: https://www.agisoft.com/downloads/installer/
Best regards,
Alexey Pasumansky,
Agisoft LLC

rowild

  • Newbie
  • *
  • Posts: 26
    • View Profile
Re: Tie Points dense, but Point cloud very disappointing
« Reply #13 on: October 17, 2024, 11:32:28 AM »
@Alexey Pasumansky - thank you very much for your guidance and detailed support! It helped, the point cloud turned out to be rather nice! :-)