Add a new community pipeline

[nagolinc]

This PR adds an img2img pipeline for Latent Consistency Models: luosiallen/latent-consistency-model#8 (comment)

examples/community/latent_consistency_img2img.py

which can be called like this

import torch
from diffusers import DiffusionPipeline

pipe = DiffusionPipeline.from_pretrained(
"SimianLuo/LCM_Dreamshaper_v7", custom_pipeline="latent_consistency_txt2img", custom_revision="main")

        # To save GPU memory, torch.float16 can be used, but it may compromise image quality.

pipe.to(torch_device="cuda", torch_dtype=torch.float32)

img2img=LatentConsistencyModelPipeline_img2img(
vae=pipe.vae,
text_encoder=pipe.text_encoder,
tokenizer=pipe.tokenizer,
unet=pipe.unet,
#scheduler=pipe.scheduler,
scheduler=None,
safety_checker=None,
feature_extractor=pipe.feature_extractor,
requires_safety_checker=False,
)

img = Image.open("thisismyimage.png")

result = img2img(prompt,img,strength,num_inference_steps=4)

What does this PR do?

Fixes # (issue)

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[patrickvonplaten]

Cool addition! Could we maybe also add a small entry to the README here: https://github.com/huggingface/diffusers/tree/main/examples/community#latent-consistency-pipeline

[HuggingFaceDocBuilderDev]

The documentation is not available anymore as the PR was closed or merged.

[nagolinc]

would reformat /home/runner/work/diffusers/diffusers/examples/community/latent_consistency_img2img.py

which formatter do I need to run?

[patrickvonplaten]

make style => I can run it on "main"

[nagolinc]

thanks!

[Zaniyar]

Cool addition! Could we maybe also add a small entry to the README here: https://github.com/huggingface/diffusers/tree/main/examples/community#latent-consistency-pipeline

 from diffusers import Diffusionpipeline
ImportError: cannot import name 'Diffusionpipeline' from 'diffusers' (/home/user/anaconda3/lib/python3.11/site-packages/diffusers/__init__.py)

I tried:
$ conda install -c conda-forge diffusers
$ conda install diffusers
$ pip install diffusers
$ pip3 install diffusers

it is installed, but can't be imported in python - any ideas?

user@Desktop:/mnt/c/Users/user/projects/code/realtimeDiffusion$ pip install diffuser
Defaulting to user installation because normal site-packages is not writeable
Requirement already satisfied: diffuser in /home/user/.local/lib/python3.10/site-packages (0.0.1)

user@Desktop:/mnt/c/Users/user/projects/code/realtimeDiffusion$ python3 bild2bild.py 
/home/user/.local/lib/python3.10/site-packages/huggingface_hub/file_download.py:672: FutureWarning: 'cached_download' is the legacy way to download files from the HF hub, please consider upgrading to 'hf_hub_download'
  warnings.warn(
Traceback (most recent call last):
  File "/mnt/c/Users/user/projects/code/realtimeDiffusion/bild2bild.py", line 12, in <module>
    pipe = LDMTextToImagePipeline.from_pretrained(model_id_or_path, torch_dtype=torch.float16, custom_pipeline="pipeline_fabric").to("cuda")
  File "/home/user/.local/lib/python3.10/site-packages/diffusers/pipelines/pipeline_utils.py", line 1078, in from_pretrained
    cached_folder = cls.download(
  File "/home/user/.local/lib/python3.10/site-packages/diffusers/pipelines/pipeline_utils.py", line 1754, in download
    pipeline_class = _get_pipeline_class(
  File "/home/user/.local/lib/python3.10/site-packages/diffusers/pipelines/pipeline_utils.py", line 360, in _get_pipeline_class
    return get_class_from_dynamic_module(
  File "/home/user/.local/lib/python3.10/site-packages/diffusers/utils/dynamic_modules_utils.py", line 445, in get_class_from_dynamic_module
    final_module = get_cached_module_file(
  File "/home/user/.local/lib/python3.10/site-packages/diffusers/utils/dynamic_modules_utils.py", line 318, in get_cached_module_file
    modules_needed = check_imports(resolved_module_file)
  File "/home/user/.local/lib/python3.10/site-packages/diffusers/utils/dynamic_modules_utils.py", line 150, in check_imports
    raise ImportError(
ImportError: This modeling file requires the following packages that were not found in your environment: diffuser. Run `pip install diffuser`