🚀[FEA]: CorrDiff training/inference without regression

[jleinonen]

Is this a new feature, an improvement, or a change to existing functionality?

New Feature

How would you describe the priority of this feature request

Medium

Please provide a clear description of problem you would like to solve.

For comparison purposes it would be good to have the ability to train CorrDiff with a plain diffusion model without regression.

Describe any alternatives you have considered

It's possible to do this by plugging in a "regression" model that returns all zeros but this is a rather hacky solution.