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[Community Pipelines] K-Diffusion Pipeline (#1360)
* up * add readme * up * uP
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@@ -22,6 +22,7 @@ If a community doesn't work as expected, please open an issue and ping the autho
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| Image to Image Inpainting Stable Diffusion | Stable Diffusion Pipeline that enables the overlaying of two images and subsequent inpainting| [Image to Image Inpainting Stable Diffusion](#image-to-image-inpainting-stable-diffusion) | - | [Alex McKinney](https://github.com/vvvm23) |
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| Text Based Inpainting Stable Diffusion | Stable Diffusion Inpainting Pipeline that enables passing a text prompt to generate the mask for inpainting| [Text Based Inpainting Stable Diffusion](#image-to-image-inpainting-stable-diffusion) | - | [Dhruv Karan](https://github.com/unography) |
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| Bit Diffusion | Diffusion on discrete data | [Bit Diffusion](#bit-diffusion) | - |[Stuti R.](https://github.com/kingstut) |
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| K-Diffusion Stable Diffusion | Run Stable Diffusion with any of [K-Diffusion's samplers](https://github.com/crowsonkb/k-diffusion/blob/master/k_diffusion/sampling.py) | [Stable Diffusion with K Diffusion](#stable-diffusion-with-k-diffusion) | - | [Patrick von Platen](https://github.com/patrickvonplaten/) |
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@@ -663,4 +664,65 @@ Based https://arxiv.org/abs/2208.04202, this is used for diffusion on discrete d
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from diffusers import DiffusionPipeline
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pipe = DiffusionPipeline.from_pretrained("google/ddpm-cifar10-32", custom_pipeline="bit_diffusion")
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image = pipe().images[0]
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```
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### Stable Diffusion with K Diffusion
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Make sure you have @crowsonkb's https://github.com/crowsonkb/k-diffusion installed:
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```
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pip install k-diffusion
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```
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You can use the community pipeline as follows:
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```python
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from diffusers import DiffusionPipeline
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pipe = DiffusionPipeline.from_pretrained("CompVis/stable-diffusion-v1-4", custom_pipeline="sd_text2img_k_diffusion")
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pipe = pipe.to("cuda")
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prompt = "an astronaut riding a horse on mars"
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pipe.set_sampler("sample_heun")
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generator = torch.Generator(device="cuda").manual_seed(seed)
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image = pipe(prompt, generator=generator, num_inference_steps=20).images[0]
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image.save("./astronaut_heun_k_diffusion.png")
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```
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To make sure that K Diffusion and `diffusers` yield the same results:
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**Diffusers**:
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```python
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from diffusers import DiffusionPipeline, EulerDiscreteScheduler
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seed = 33
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pipe = DiffusionPipeline.from_pretrained("CompVis/stable-diffusion-v1-4")
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pipe.scheduler = EulerDiscreteScheduler.from_config(pipe.scheduler.config)
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pipe = pipe.to("cuda")
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generator = torch.Generator(device="cuda").manual_seed(seed)
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image = pipe(prompt, generator=generator, num_inference_steps=50).images[0]
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```
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**K Diffusion**:
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```python
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from diffusers import DiffusionPipeline, EulerDiscreteScheduler
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seed = 33
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pipe = DiffusionPipeline.from_pretrained("CompVis/stable-diffusion-v1-4", custom_pipeline="sd_text2img_k_diffusion")
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pipe.scheduler = EulerDiscreteScheduler.from_config(pipe.scheduler.config)
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pipe = pipe.to("cuda")
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pipe.set_sampler("sample_euler")
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generator = torch.Generator(device="cuda").manual_seed(seed)
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image = pipe(prompt, generator=generator, num_inference_steps=50).images[0]
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```
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479
examples/community/sd_text2img_k_diffusion.py
Executable file
479
examples/community/sd_text2img_k_diffusion.py
Executable file
@@ -0,0 +1,479 @@
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# Copyright 2022 The HuggingFace Team. All rights reserved.
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#
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# Licensed under the Apache License, Version 2.0 (the "License");
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# you may not use this file except in compliance with the License.
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# You may obtain a copy of the License at
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#
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# http://www.apache.org/licenses/LICENSE-2.0
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#
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# Unless required by applicable law or agreed to in writing, software
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# distributed under the License is distributed on an "AS IS" BASIS,
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# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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# See the License for the specific language governing permissions and
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# limitations under the License.
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import importlib
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from typing import Callable, List, Optional, Union
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import torch
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from diffusers import LMSDiscreteScheduler
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from diffusers.pipeline_utils import DiffusionPipeline
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from diffusers.pipelines.stable_diffusion import StableDiffusionPipelineOutput
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from diffusers.utils import is_accelerate_available, logging
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from k_diffusion.external import CompVisDenoiser
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logger = logging.get_logger(__name__) # pylint: disable=invalid-name
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class ModelWrapper:
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def __init__(self, model, alphas_cumprod):
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self.model = model
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self.alphas_cumprod = alphas_cumprod
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def apply_model(self, *args, **kwargs):
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return self.model(*args, **kwargs).sample
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class StableDiffusionPipeline(DiffusionPipeline):
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r"""
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Pipeline for text-to-image generation using Stable Diffusion.
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This model inherits from [`DiffusionPipeline`]. Check the superclass documentation for the generic methods the
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library implements for all the pipelines (such as downloading or saving, running on a particular device, etc.)
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Args:
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vae ([`AutoencoderKL`]):
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Variational Auto-Encoder (VAE) Model to encode and decode images to and from latent representations.
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text_encoder ([`CLIPTextModel`]):
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Frozen text-encoder. Stable Diffusion uses the text portion of
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[CLIP](https://huggingface.co/docs/transformers/model_doc/clip#transformers.CLIPTextModel), specifically
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the [clip-vit-large-patch14](https://huggingface.co/openai/clip-vit-large-patch14) variant.
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tokenizer (`CLIPTokenizer`):
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Tokenizer of class
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[CLIPTokenizer](https://huggingface.co/docs/transformers/v4.21.0/en/model_doc/clip#transformers.CLIPTokenizer).
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unet ([`UNet2DConditionModel`]): Conditional U-Net architecture to denoise the encoded image latents.
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scheduler ([`SchedulerMixin`]):
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A scheduler to be used in combination with `unet` to denoise the encoded image latents. Can be one of
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[`DDIMScheduler`], [`LMSDiscreteScheduler`], or [`PNDMScheduler`].
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safety_checker ([`StableDiffusionSafetyChecker`]):
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Classification module that estimates whether generated images could be considered offensive or harmful.
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Please, refer to the [model card](https://huggingface.co/runwayml/stable-diffusion-v1-5) for details.
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feature_extractor ([`CLIPFeatureExtractor`]):
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Model that extracts features from generated images to be used as inputs for the `safety_checker`.
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"""
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def __init__(
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self,
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vae,
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text_encoder,
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tokenizer,
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unet,
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scheduler,
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safety_checker,
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feature_extractor,
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):
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super().__init__()
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if safety_checker is None:
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logger.warn(
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f"You have disabled the safety checker for {self.__class__} by passing `safety_checker=None`. Ensure"
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" that you abide to the conditions of the Stable Diffusion license and do not expose unfiltered"
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" results in services or applications open to the public. Both the diffusers team and Hugging Face"
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" strongly recommend to keep the safety filter enabled in all public facing circumstances, disabling"
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" it only for use-cases that involve analyzing network behavior or auditing its results. For more"
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" information, please have a look at https://github.com/huggingface/diffusers/pull/254 ."
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)
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# get correct sigmas from LMS
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scheduler = LMSDiscreteScheduler.from_config(scheduler.config)
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self.register_modules(
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vae=vae,
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text_encoder=text_encoder,
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tokenizer=tokenizer,
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unet=unet,
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scheduler=scheduler,
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safety_checker=safety_checker,
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feature_extractor=feature_extractor,
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)
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model = ModelWrapper(unet, scheduler.alphas_cumprod)
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self.k_diffusion_model = CompVisDenoiser(model)
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def set_sampler(self, scheduler_type: str):
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library = importlib.import_module("k_diffusion")
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sampling = getattr(library, "sampling")
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self.sampler = getattr(sampling, scheduler_type)
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def enable_xformers_memory_efficient_attention(self):
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r"""
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Enable memory efficient attention as implemented in xformers.
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When this option is enabled, you should observe lower GPU memory usage and a potential speed up at inference
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time. Speed up at training time is not guaranteed.
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Warning: When Memory Efficient Attention and Sliced attention are both enabled, the Memory Efficient Attention
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is used.
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"""
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self.unet.set_use_memory_efficient_attention_xformers(True)
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def disable_xformers_memory_efficient_attention(self):
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r"""
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Disable memory efficient attention as implemented in xformers.
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"""
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self.unet.set_use_memory_efficient_attention_xformers(False)
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def enable_attention_slicing(self, slice_size: Optional[Union[str, int]] = "auto"):
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r"""
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Enable sliced attention computation.
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When this option is enabled, the attention module will split the input tensor in slices, to compute attention
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in several steps. This is useful to save some memory in exchange for a small speed decrease.
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Args:
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slice_size (`str` or `int`, *optional*, defaults to `"auto"`):
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When `"auto"`, halves the input to the attention heads, so attention will be computed in two steps. If
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a number is provided, uses as many slices as `attention_head_dim // slice_size`. In this case,
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`attention_head_dim` must be a multiple of `slice_size`.
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"""
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if slice_size == "auto":
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# half the attention head size is usually a good trade-off between
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# speed and memory
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slice_size = self.unet.config.attention_head_dim // 2
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self.unet.set_attention_slice(slice_size)
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def disable_attention_slicing(self):
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r"""
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Disable sliced attention computation. If `enable_attention_slicing` was previously invoked, this method will go
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back to computing attention in one step.
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"""
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# set slice_size = `None` to disable `attention slicing`
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self.enable_attention_slicing(None)
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def enable_sequential_cpu_offload(self, gpu_id=0):
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r"""
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Offloads all models to CPU using accelerate, significantly reducing memory usage. When called, unet,
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text_encoder, vae and safety checker have their state dicts saved to CPU and then are moved to a
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`torch.device('meta') and loaded to GPU only when their specific submodule has its `forward` method called.
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"""
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if is_accelerate_available():
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from accelerate import cpu_offload
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else:
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raise ImportError("Please install accelerate via `pip install accelerate`")
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device = torch.device(f"cuda:{gpu_id}")
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for cpu_offloaded_model in [self.unet, self.text_encoder, self.vae, self.safety_checker]:
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if cpu_offloaded_model is not None:
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cpu_offload(cpu_offloaded_model, device)
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@property
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def _execution_device(self):
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r"""
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Returns the device on which the pipeline's models will be executed. After calling
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`pipeline.enable_sequential_cpu_offload()` the execution device can only be inferred from Accelerate's module
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hooks.
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"""
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if self.device != torch.device("meta") or not hasattr(self.unet, "_hf_hook"):
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return self.device
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for module in self.unet.modules():
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if (
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hasattr(module, "_hf_hook")
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and hasattr(module._hf_hook, "execution_device")
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and module._hf_hook.execution_device is not None
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):
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return torch.device(module._hf_hook.execution_device)
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return self.device
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def _encode_prompt(self, prompt, device, num_images_per_prompt, do_classifier_free_guidance, negative_prompt):
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r"""
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Encodes the prompt into text encoder hidden states.
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Args:
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prompt (`str` or `list(int)`):
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prompt to be encoded
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device: (`torch.device`):
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torch device
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num_images_per_prompt (`int`):
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number of images that should be generated per prompt
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do_classifier_free_guidance (`bool`):
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whether to use classifier free guidance or not
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negative_prompt (`str` or `List[str]`):
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The prompt or prompts not to guide the image generation. Ignored when not using guidance (i.e., ignored
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if `guidance_scale` is less than `1`).
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"""
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batch_size = len(prompt) if isinstance(prompt, list) else 1
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text_inputs = self.tokenizer(
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prompt,
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padding="max_length",
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max_length=self.tokenizer.model_max_length,
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truncation=True,
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return_tensors="pt",
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)
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text_input_ids = text_inputs.input_ids
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untruncated_ids = self.tokenizer(prompt, padding="max_length", return_tensors="pt").input_ids
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if not torch.equal(text_input_ids, untruncated_ids):
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removed_text = self.tokenizer.batch_decode(untruncated_ids[:, self.tokenizer.model_max_length - 1 : -1])
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logger.warning(
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"The following part of your input was truncated because CLIP can only handle sequences up to"
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f" {self.tokenizer.model_max_length} tokens: {removed_text}"
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)
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if hasattr(self.text_encoder.config, "use_attention_mask") and self.text_encoder.config.use_attention_mask:
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attention_mask = text_inputs.attention_mask.to(device)
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else:
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attention_mask = None
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text_embeddings = self.text_encoder(
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text_input_ids.to(device),
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attention_mask=attention_mask,
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)
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text_embeddings = text_embeddings[0]
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# duplicate text embeddings for each generation per prompt, using mps friendly method
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bs_embed, seq_len, _ = text_embeddings.shape
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text_embeddings = text_embeddings.repeat(1, num_images_per_prompt, 1)
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text_embeddings = text_embeddings.view(bs_embed * num_images_per_prompt, seq_len, -1)
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# get unconditional embeddings for classifier free guidance
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if do_classifier_free_guidance:
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uncond_tokens: List[str]
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if negative_prompt is None:
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uncond_tokens = [""] * batch_size
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elif type(prompt) is not type(negative_prompt):
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raise TypeError(
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f"`negative_prompt` should be the same type to `prompt`, but got {type(negative_prompt)} !="
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f" {type(prompt)}."
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)
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elif isinstance(negative_prompt, str):
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uncond_tokens = [negative_prompt]
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elif batch_size != len(negative_prompt):
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raise ValueError(
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f"`negative_prompt`: {negative_prompt} has batch size {len(negative_prompt)}, but `prompt`:"
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f" {prompt} has batch size {batch_size}. Please make sure that passed `negative_prompt` matches"
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" the batch size of `prompt`."
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)
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else:
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uncond_tokens = negative_prompt
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max_length = text_input_ids.shape[-1]
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uncond_input = self.tokenizer(
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uncond_tokens,
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padding="max_length",
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max_length=max_length,
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truncation=True,
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return_tensors="pt",
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)
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if hasattr(self.text_encoder.config, "use_attention_mask") and self.text_encoder.config.use_attention_mask:
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attention_mask = uncond_input.attention_mask.to(device)
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else:
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attention_mask = None
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uncond_embeddings = self.text_encoder(
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uncond_input.input_ids.to(device),
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attention_mask=attention_mask,
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)
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uncond_embeddings = uncond_embeddings[0]
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# duplicate unconditional embeddings for each generation per prompt, using mps friendly method
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seq_len = uncond_embeddings.shape[1]
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uncond_embeddings = uncond_embeddings.repeat(1, num_images_per_prompt, 1)
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uncond_embeddings = uncond_embeddings.view(batch_size * num_images_per_prompt, seq_len, -1)
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# For classifier free guidance, we need to do two forward passes.
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# Here we concatenate the unconditional and text embeddings into a single batch
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# to avoid doing two forward passes
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text_embeddings = torch.cat([uncond_embeddings, text_embeddings])
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return text_embeddings
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def run_safety_checker(self, image, device, dtype):
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if self.safety_checker is not None:
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safety_checker_input = self.feature_extractor(self.numpy_to_pil(image), return_tensors="pt").to(device)
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image, has_nsfw_concept = self.safety_checker(
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images=image, clip_input=safety_checker_input.pixel_values.to(dtype)
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)
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else:
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has_nsfw_concept = None
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return image, has_nsfw_concept
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def decode_latents(self, latents):
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latents = 1 / 0.18215 * latents
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image = self.vae.decode(latents).sample
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image = (image / 2 + 0.5).clamp(0, 1)
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# we always cast to float32 as this does not cause significant overhead and is compatible with bfloa16
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image = image.cpu().permute(0, 2, 3, 1).float().numpy()
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return image
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def check_inputs(self, prompt, height, width, callback_steps):
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if not isinstance(prompt, str) and not isinstance(prompt, list):
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raise ValueError(f"`prompt` has to be of type `str` or `list` but is {type(prompt)}")
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if height % 8 != 0 or width % 8 != 0:
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raise ValueError(f"`height` and `width` have to be divisible by 8 but are {height} and {width}.")
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if (callback_steps is None) or (
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callback_steps is not None and (not isinstance(callback_steps, int) or callback_steps <= 0)
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):
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raise ValueError(
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f"`callback_steps` has to be a positive integer but is {callback_steps} of type"
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f" {type(callback_steps)}."
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)
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def prepare_latents(self, batch_size, num_channels_latents, height, width, dtype, device, generator, latents=None):
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shape = (batch_size, num_channels_latents, height // 8, width // 8)
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if latents is None:
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if device.type == "mps":
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# randn does not work reproducibly on mps
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latents = torch.randn(shape, generator=generator, device="cpu", dtype=dtype).to(device)
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else:
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latents = torch.randn(shape, generator=generator, device=device, dtype=dtype)
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else:
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if latents.shape != shape:
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raise ValueError(f"Unexpected latents shape, got {latents.shape}, expected {shape}")
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latents = latents.to(device)
|
||||
|
||||
# scale the initial noise by the standard deviation required by the scheduler
|
||||
return latents
|
||||
|
||||
@torch.no_grad()
|
||||
def __call__(
|
||||
self,
|
||||
prompt: Union[str, List[str]],
|
||||
height: int = 512,
|
||||
width: int = 512,
|
||||
num_inference_steps: int = 50,
|
||||
guidance_scale: float = 7.5,
|
||||
negative_prompt: Optional[Union[str, List[str]]] = None,
|
||||
num_images_per_prompt: Optional[int] = 1,
|
||||
eta: float = 0.0,
|
||||
generator: Optional[torch.Generator] = None,
|
||||
latents: Optional[torch.FloatTensor] = None,
|
||||
output_type: Optional[str] = "pil",
|
||||
return_dict: bool = True,
|
||||
callback: Optional[Callable[[int, int, torch.FloatTensor], None]] = None,
|
||||
callback_steps: Optional[int] = 1,
|
||||
**kwargs,
|
||||
):
|
||||
r"""
|
||||
Function invoked when calling the pipeline for generation.
|
||||
|
||||
Args:
|
||||
prompt (`str` or `List[str]`):
|
||||
The prompt or prompts to guide the image generation.
|
||||
height (`int`, *optional*, defaults to 512):
|
||||
The height in pixels of the generated image.
|
||||
width (`int`, *optional*, defaults to 512):
|
||||
The width in pixels of the generated image.
|
||||
num_inference_steps (`int`, *optional*, defaults to 50):
|
||||
The number of denoising steps. More denoising steps usually lead to a higher quality image at the
|
||||
expense of slower inference.
|
||||
guidance_scale (`float`, *optional*, defaults to 7.5):
|
||||
Guidance scale as defined in [Classifier-Free Diffusion Guidance](https://arxiv.org/abs/2207.12598).
|
||||
`guidance_scale` is defined as `w` of equation 2. of [Imagen
|
||||
Paper](https://arxiv.org/pdf/2205.11487.pdf). Guidance scale is enabled by setting `guidance_scale >
|
||||
1`. Higher guidance scale encourages to generate images that are closely linked to the text `prompt`,
|
||||
usually at the expense of lower image quality.
|
||||
negative_prompt (`str` or `List[str]`, *optional*):
|
||||
The prompt or prompts not to guide the image generation. Ignored when not using guidance (i.e., ignored
|
||||
if `guidance_scale` is less than `1`).
|
||||
num_images_per_prompt (`int`, *optional*, defaults to 1):
|
||||
The number of images to generate per prompt.
|
||||
eta (`float`, *optional*, defaults to 0.0):
|
||||
Corresponds to parameter eta (η) in the DDIM paper: https://arxiv.org/abs/2010.02502. Only applies to
|
||||
[`schedulers.DDIMScheduler`], will be ignored for others.
|
||||
generator (`torch.Generator`, *optional*):
|
||||
A [torch generator](https://pytorch.org/docs/stable/generated/torch.Generator.html) to make generation
|
||||
deterministic.
|
||||
latents (`torch.FloatTensor`, *optional*):
|
||||
Pre-generated noisy latents, sampled from a Gaussian distribution, to be used as inputs for image
|
||||
generation. Can be used to tweak the same generation with different prompts. If not provided, a latents
|
||||
tensor will ge generated by sampling using the supplied random `generator`.
|
||||
output_type (`str`, *optional*, defaults to `"pil"`):
|
||||
The output format of the generate image. Choose between
|
||||
[PIL](https://pillow.readthedocs.io/en/stable/): `PIL.Image.Image` or `np.array`.
|
||||
return_dict (`bool`, *optional*, defaults to `True`):
|
||||
Whether or not to return a [`~pipelines.stable_diffusion.StableDiffusionPipelineOutput`] instead of a
|
||||
plain tuple.
|
||||
callback (`Callable`, *optional*):
|
||||
A function that will be called every `callback_steps` steps during inference. The function will be
|
||||
called with the following arguments: `callback(step: int, timestep: int, latents: torch.FloatTensor)`.
|
||||
callback_steps (`int`, *optional*, defaults to 1):
|
||||
The frequency at which the `callback` function will be called. If not specified, the callback will be
|
||||
called at every step.
|
||||
|
||||
Returns:
|
||||
[`~pipelines.stable_diffusion.StableDiffusionPipelineOutput`] or `tuple`:
|
||||
[`~pipelines.stable_diffusion.StableDiffusionPipelineOutput`] if `return_dict` is True, otherwise a `tuple.
|
||||
When returning a tuple, the first element is a list with the generated images, and the second element is a
|
||||
list of `bool`s denoting whether the corresponding generated image likely represents "not-safe-for-work"
|
||||
(nsfw) content, according to the `safety_checker`.
|
||||
"""
|
||||
|
||||
# 1. Check inputs. Raise error if not correct
|
||||
self.check_inputs(prompt, height, width, callback_steps)
|
||||
|
||||
# 2. Define call parameters
|
||||
batch_size = 1 if isinstance(prompt, str) else len(prompt)
|
||||
device = self._execution_device
|
||||
# here `guidance_scale` is defined analog to the guidance weight `w` of equation (2)
|
||||
# of the Imagen paper: https://arxiv.org/pdf/2205.11487.pdf . `guidance_scale = 1`
|
||||
# corresponds to doing no classifier free guidance.
|
||||
do_classifier_free_guidance = True
|
||||
if guidance_scale <= 1.0:
|
||||
raise ValueError("has to use guidance_scale")
|
||||
|
||||
# 3. Encode input prompt
|
||||
text_embeddings = self._encode_prompt(
|
||||
prompt, device, num_images_per_prompt, do_classifier_free_guidance, negative_prompt
|
||||
)
|
||||
|
||||
# 4. Prepare timesteps
|
||||
self.scheduler.set_timesteps(num_inference_steps, device=text_embeddings.device)
|
||||
sigmas = self.scheduler.sigmas
|
||||
|
||||
# 5. Prepare latent variables
|
||||
num_channels_latents = self.unet.in_channels
|
||||
latents = self.prepare_latents(
|
||||
batch_size * num_images_per_prompt,
|
||||
num_channels_latents,
|
||||
height,
|
||||
width,
|
||||
text_embeddings.dtype,
|
||||
device,
|
||||
generator,
|
||||
latents,
|
||||
)
|
||||
latents = latents * sigmas[0]
|
||||
self.k_diffusion_model.sigmas = self.k_diffusion_model.sigmas.to(latents.device)
|
||||
self.k_diffusion_model.log_sigmas = self.k_diffusion_model.log_sigmas.to(latents.device)
|
||||
|
||||
def model_fn(x, t):
|
||||
latent_model_input = torch.cat([x] * 2)
|
||||
|
||||
noise_pred = self.k_diffusion_model(latent_model_input, t, encoder_hidden_states=text_embeddings)
|
||||
|
||||
noise_pred_uncond, noise_pred_text = noise_pred.chunk(2)
|
||||
noise_pred = noise_pred_uncond + guidance_scale * (noise_pred_text - noise_pred_uncond)
|
||||
return noise_pred
|
||||
|
||||
latents = self.sampler(model_fn, latents, sigmas)
|
||||
|
||||
# 8. Post-processing
|
||||
image = self.decode_latents(latents)
|
||||
|
||||
# 9. Run safety checker
|
||||
image, has_nsfw_concept = self.run_safety_checker(image, device, text_embeddings.dtype)
|
||||
|
||||
# 10. Convert to PIL
|
||||
if output_type == "pil":
|
||||
image = self.numpy_to_pil(image)
|
||||
|
||||
if not return_dict:
|
||||
return (image, has_nsfw_concept)
|
||||
|
||||
return StableDiffusionPipelineOutput(images=image, nsfw_content_detected=has_nsfw_concept)
|
||||
Reference in New Issue
Block a user