Generating images with img_size=512

I'm trying to get (Janus Pro)[https://huggingface.co/deepseek-ai/Janus-Pro-7B] text-to-image to work with the example code from this repo, and it keeps generating garbled images if parameters like image size and patch size are changed from the defaults given in the example. I have the gist with the changed parameters here:

https://gist.github.com/ivoras/0d61dfa4092388ce960745f1d19d2612

In it, if img_size is changed to 512 or patch_size is changed to 8, the generated images are garbled.

Did anyone manage to get it work in the general case, or suggest where the problems might be?