The 3D textured mesh is generated based on the point cloud. All the points of the densified point cloud are used for the generation of the mesh. Therefore, any errors in the 3D points are reflected on the 3D mesh. Thus, the first step for assessing the quality of your outputs is to click on random points in the point cloud and check their reprojection on the images.
To do so, simply hover the mouse above the point cloud and click at a random point. Then, on the right side bar you will see how this point is reprojected on the images. If the reprojection is incorrect, you may mark more GCPs in that area or add MTPs and reoptimize the project.
Are they correctly reprojected on the images?
I assume that the two software (Pix4D Desktop and Bentley ContextCapture) are using a different point cloud for the mesh generation. I am not familiar with ContextCapture software, so I cannot assess the quality of this output.
I can though provide some recommendations for improving the results:
- Increase the maximum number of triangles of the 3D textured mesh. This will help to render the finer details in the model.
- Select High Resolution , so that the parameters values yielding a high resolution mesh are selected.
Process > Processing Options > 2. Point Cloud and Mesh > 3D Textured Mesh tab > Settings > High Resolution.
- Select Custom.
Process > Processing Options > 2. Point Cloud and Mesh > 3D Textured Mesh tab > Settings > Custom.
- In Decimation Criteria, select Quantitative.
- In Maximum Number of Triangles, introduce a higher value. I suggest starting with a value 10 times higher, i.e. 10000000.
If it does not help, you could try improving the quality of the point cloud:
- Adjust the parameters of the point cloud densification, to get denser point cloud
Process > Processing Options > 2. Point Cloud and Mesh > Point Cloud tab _> Point Cloud Densification > s_et the Minimum Number of Matches to 5.
Draw surfaces that will be used in the generation of DSM and 3D Textured Mesh.
- Remove the noise from the point cloud using the Point Cloud Editor before generating 3D models of your data set (3D Textured Mesh, DSM/DTM).
For more information about how to remove noise from the point cloud, you can take a look here: https://support.pix4d.com/hc/en-us/articles/204085149.
I hope this helps to improve the quality of the 3D textured mesh.