Generated texture is not smooth

[coderSinol]

First of all, this is a great project. Thanks for sharing.

I tried the given sample mansion.zip. However, it generated a texture like this for grass, it is not smooth and contains 4 tile-like areas. Do you have any suggestions to improve this?

[wonjunior]

Hi @coderSinol, I appreciate your comment, I also noticed this happening in some instances. During denoising, noise unrolling only enforces a local constraint such that the content of contiguous patches is aligned after decoding. Since decoding is done in batches, the stitching won't be perfectly continuous. I believe the shift in appearance between patches originates from the separate decoding.

It wasn't made very clear in my code but you can try to apply a renormalization step (at the image level after decoding) to try to counter that. It normalizes the patch means with the mean of the entire image. Something like this:

lmean = image_stack.mean(dim=(-1,-2), keepdim=True)
gmean = image_stack.mean(dim=(0,2,3), keepdim=True)
image_stack = image_stack*gmean/lmean

When there are outliers, this might lead to major artifacts, however. So I recommend you also experiment by aligning the median. Let me know if that helps!