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Pix4D uses images from another group to produce point cloud

Dear Community,
I have a pix4D project with images from two different cameras (NIR and RGB). Therefore, I have assigned the images to two different groups in the image properties editor before starting the processes. I have now finished step 2 and when I load the densified point clouds I do have two point cloud groups as expected. But when I click on points in the point cloud (from one group) I see that images from both NIR and RGB have been used. Is that normal? I also find that the RGB point cloud looks very gray compared to other projects that I have done.
Best regards

Hi @jehammar,

Image Groups allow to define which image groups are used to generate each of three different outputs: the Point Cloud, the Mesh Geometry and the Mesh Texture. It is useful for projects that consist of images of different band configuration like yours. For a project that consists of both RGB and NIR images, the point cloud can be generated based on both the RGB and the NIR images. As a result if you used both groups to generate the pointcloud then when selecting a point in the point cloud it is expected to notice that images from both NIR and RGB have been used.

You also said that the RGB point cloud looks very gray compared to other projects. Can you share with me the quality report (pdf format) the log file and some screenshots of the issue. Have you checked your images RGB images to see if this problem also exists on them? Have you upgraded your GPU drivers recently?

Best,

Hello @Nikoleta_Dimopoulou,

if I understand it correct I will find points used from the NIR in my RGB point cloud as well as long as I have selected both groups in the advanced options:

So to make sure, that in my RGB point cloud only RGB images are used I need to uncheck NIR? I have not upgraded the GPY servers recently and I attached my log and report.
The RGB orthophoto on the end looks great by the way and not gray as the point cloud.

TVC_small_roi_report.pdf (248.7 KB)
the log file is too big to upload.

First a screenshot of a project (project 1) from the RGB point cloud:

And here is a screenshot of an another project (project 2) from the same region:

I have used the same images for both projects the only difference is that I used an individual histogram stretch in project 2. Here are an example of the images used:
project 1:


Project 2:

The reason why I decided not to use histogram stretch was that some images then got saturated.

Hi,

May I ask if you are experiencing any issues?
I would suggest to you to have a look at this article if you want to process a dataset with both thermal and RGB imagery and follow instructions of this section:

Best,

Hello, the issue I have is that the RGB pointcloud appears gray (as seen in the photos above) and if I want to use the colour for classification I would need the point cloud to appear in RGB colors as in the photo from project 2 above.

Hello again @Nikoleta_Dimopoulou,
since my goal is to perform a classification on the point cloud based on the color I need to figure out how I can get a nice looking RGB colored point cloud again as I did in the previous projects. What I also see is that in the map view in Pix4D the images appear in RGB:


But then in the Raycloud they appear gray:

Consequently, the RGB point cloud also is gray…
If you have any idea on what I am doing wrong here please let me know :slight_smile:

Hi,

Would it be possible to share the images with us?

Best,