Question about 2D GS

[Boris-Cui]

Hello, thank you for your work. I would like to try integrating 2D GS into the method you used for 3D GS. However, after the integration, the following issue arises: surface reconstruction can be completed, but there are artifacts resembling light reflections around the surroundings, as shown in the image below. Moreover, this phenomenon intensifies with the increase in the number of iterations. At 500 iterations, it is almost non-existent; at 1000 iterations, a few artifacts start to appear. The following image shows the situation in 3000 iterations.
Could you analyze what might be causing this?

[ddenglina]

I have same question. Have you see mesh file? how about mesh quality?

[Boris-Cui]

I have same question. Have you see mesh file? how about mesh quality?

I didn't export the mesh. How is your mesh result?

[ddenglina]

I have same question. Have you see mesh file? how about mesh quality?

I didn't export the mesh. How is your mesh result?

I used 30 images, After instantsplat I got pose and point cloud. Then put them into 2dgs. The mesh is so bad!

[kairunwen]

@Boris-Cui Hi, thank you for your interest! It’s possible that during the early stages of training, the scale of the Gaussian points is relatively small. However, when photometric constraints are insufficient, the Gaussians may elongate along the viewing direction as training progresses (as shown below), thus leading to "artifacts that resemble light reflections around the surrounding areas".

Here are three solutions that could work.

• Impose a constraint on scale. code muskie82/MonoGS#53.
• Use isotropic Gaussians instead of anisotropic Gaussians. Many surfels are like spikes hbb1/2d-gaussian-splatting#56.
• Reduce the learning rate of the scale of Gaussians here.

[kairunwen]

@ddenglina Hi, could you show us the mesh visualization results so we can analyze them?

[kairunwen]

@ddenglina Hi, you can find the code here: https://github.com/NVlabs/InstantSplat/tree/instantsplat-2dgs. You can run the script bash scripts/run_infer.sh to generate the mesh shown below.