Topics

1

General / 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?

2

General / Batch Process offers "Point Spacing" for "Build Point Cloud"...

« on: October 07, 2024, 05:47:40 PM »

...but the regular "Build Point Cloud" interface does not. I am sure I miss something: Maybe the feature is called differently? Or is there a reason why this option is not available in the "regular mode"?

3

General / Adjust red rectangle to view?

« on: October 05, 2024, 10:00:37 AM »

Hi!

Beginner here. I created a pointcloud and would like to adjust it to the XYZ coordinates. The result of that can be seen in the attached screenshot. The red rectangle though does not seem to be adjustable to the view of the model.

I do not really know what the red rectangle means: does it define the "world coordinates", while the gray transparent rectangle establishes "local coordinates"?

Is there any way to align the red rectangle with the gray one? (So that world and local coordiantes are the same?)

Thank you!

4

General / Extracting images from imported Video does not respect frame steps?

« on: December 27, 2023, 09:58:07 AM »

I use the video importer to extract images from there. Usually I want to extract every 15th frame from a 30fps video, so I enter 15 in the "frame step" input field, which offers a name template in the form of "frame{filenum}". But it seems it does not count the frame number, but instead the consecutively extracted file numbers.

Shouldn't it rather count the frame number given that the template says "frame{filenum}"? "frame2" is indeed not "Frame 2", when every 15th frame is extracted.
Using the correct frames would also help to identify if a specific sequence needs more images or not, so I could better pinpoint the sequence needed and extract only the images of that respective area.

5

General / Which values does "Pixel size" in "Camera type: Frame" expect?

« on: December 27, 2023, 02:21:18 AM »

I do not understand which values I am supposed to enter in the "Pixel Size" field, which appears when the "Frame" camera is chosen. The screenshot shows that I currently use 1920x1012 which is the (edited) output of a video of a DJI Mavic 3 camera (which is a frame camera, right?). (The specs of that drone camera can be found here: https://www.dji.com/at/mavic-3/specs)

I have a feeling that I am misunderstanding that input field... Any clarification would be most welcome! Thank you!

6

General / How to remove the "snow" at the edges of the point cloud

« on: December 21, 2023, 02:42:13 AM »

Hi!

I am rather new to Photogrammetry and to Metashape, which I use int he standard edition's trial version at the moment. I am particularly fascinated by the point cloud results Metashape generated and use them purely as "art".

I would like to get a little better and am currently struggeling with the problem of removing white noise at the edges of many of my point clouds. As the attached image shows, the trees in the point cloud seem to have snow on them – but there hasn't been any snow at the time of shooting those images. I assume it is an "artifact" from the bright background?

I've read that I can use the point cloud's filter option with values from 0 to 3. But those remove some green from the ground first, before any white is touched.

Is there another way to handle this "phenomenon"?

Thank you!