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Is the terminology correct for what is beta and beta_prod_t?

Open gauravjain14 opened this issue 8 months ago • 1 comments

https://github.com/hkproj/pytorch-stable-diffusion/blob/6e6900078372af15eb1b13e73068cd563784f377/sd/ddpm.py#L64C9-L64C39

The implementation makes sense from what the equations say but I was confused for a minute with using the term beta_prod_t.

What is beta? beta = 1 - alpha

and

alpha_prod_t = prod(alpha_0, alpha_1, ...., alpha_t)

What will be the product of beta till timestep t?

(IIUC) beta_prod_t = prod(1-alpha_0, 1-alpha_1, ..., 1-alpha_t)

which is not equivalent to 1 - alpha_prod_t

What do you think?

gauravjain14 avatar Mar 23 '25 21:03 gauravjain14

I think this is just a variable definition, it is definitely not equal in fact

itera-del avatar Jul 22 '25 02:07 itera-del