Why the gradient is divided by sigma? about sjc HOT 2 CLOSED

I am on my phone. Will expand once I get to laptop.

If u check out the appendix, or Karras elucidating diffusion, the instantaneous update is $- \sigma \cdot score$. Also referred to as Twedie’s formula. Although here in case of PAAS, since both $D$ and $x$ are clean images, I’d like to believe you can even not devide anything. It’s really the l2 loss gradient between 2 images both with numerical range in [-1, 1]

from sjc.

I see. Thank you so much for the explanation!

from sjc.