GitLab

* Added explanation of 'strength' parameter

* Added get_timesteps function which relies on new strength parameter

* Added `strength` parameter which defaults to 1.

* Swapped ordering so `noise_timestep` can be calculated before masking the image

this is required when you aren't applying 100% noise to the masked region, e.g. strength < 1.

* Added strength to check_inputs, throws error if out of range

* Changed `prepare_latents` to initialise latents w.r.t strength

inspired from the stable diffusion img2img pipeline, init latents are initialised by converting the init image into a VAE latent and adding noise (based upon the strength parameter passed in), e.g. random when strength = 1, or the init image at strength = 0.

* WIP: Added a unit test for the new strength parameter in the StableDiffusionInpaintingPipeline

still need to add correct regression values

* Created a is_strength_max to initialise from pure random noise

* Updated unit tests w.r.t new strength parameter + fixed new strength unit test

* renamed parameter to avoid confusion with variable of same name

* Updated regression values for new strength test - now passes

* removed 'copied from' comment as this method is now different and divergent from the cpy

* Update src/diffusers/pipelines/stable_diffusion/pipeline_stable_diffusion_inpaint.py
Co-authored-by: Patrick von Platen <patrick.v.platen@gmail.com>

* Ensure backwards compatibility for prepare_mask_and_masked_image

created a return_image boolean and initialised to false

* Ensure backwards compatibility for prepare_latents

* Fixed copy check typo

* Fixes w.r.t backward compibility changes

* make style

* keep function argument ordering same for backwards compatibility in callees with copied from statements

* make fix-copies

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Co-authored-by: Patrick von Platen <patrick.v.platen@gmail.com>
Co-authored-by: William Berman <WLBberman@gmail.com>