The parameter sigma_data for KarrasDenoiser.

[moonbow721]

Hi, thank you for your great work on this project! I have been comparing the noise schedule implementation between this project and EDM, and I noticed some odd differences. In particular, I was looking at this code snippet: https://github.com/openai/consistency_models/blob/edfe91ecd3bb1ac75166da4fac5b093977c81003/cm/script_util.py#L94-L101 The image tensors in both projects are normalized in the range [-1, 1]. Based on my understanding, the parameter "sigma_data" should be set to 1.0, similar to the EDM settings. Could you kindly clarify the reason behind the difference in the "sigma_data" value between the two projects?