Text-to-Image Generation
StableDiffusionPipeline
The Stable Diffusion model was created by the researchers and engineers from CompVis, Stability AI, runway, and LAION. The StableDiffusionPipeline is capable of generating photo-realistic images given any text input using Stable Diffusion.
The original codebase can be found here:
- Stable Diffusion V1: CompVis/stable-diffusion
- Stable Diffusion v2: Stability-AI/stablediffusion
Available Checkpoints are:
- stable-diffusion-v1-4 (512x512 resolution) CompVis/stable-diffusion-v1-4
- stable-diffusion-v1-5 (512x512 resolution) runwayml/stable-diffusion-v1-5
- stable-diffusion-2-base (512x512 resolution): stabilityai/stable-diffusion-2-base
- stable-diffusion-2 (768x768 resolution): stabilityai/stable-diffusion-2
- stable-diffusion-2-1-base (512x512 resolution) stabilityai/stable-diffusion-2-1-base
- stable-diffusion-2-1 (768x768 resolution): stabilityai/stable-diffusion-2-1
class diffusers.StableDiffusionPipeline
< source >( vae: AutoencoderKL text_encoder: CLIPTextModel tokenizer: CLIPTokenizer unet: UNet2DConditionModel scheduler: KarrasDiffusionSchedulers safety_checker: StableDiffusionSafetyChecker feature_extractor: CLIPImageProcessor requires_safety_checker: bool = True )
Parameters
- vae (AutoencoderKL) — Variational Auto-Encoder (VAE) Model to encode and decode images to and from latent representations.
-
text_encoder (
CLIPTextModel
) — Frozen text-encoder. Stable Diffusion uses the text portion of CLIP, specifically the clip-vit-large-patch14 variant. -
tokenizer (
CLIPTokenizer
) — Tokenizer of class CLIPTokenizer. - unet (UNet2DConditionModel) — Conditional U-Net architecture to denoise the encoded image latents.
-
scheduler (SchedulerMixin) —
A scheduler to be used in combination with
unet
to denoise the encoded image latents. Can be one of DDIMScheduler, LMSDiscreteScheduler, or PNDMScheduler. -
safety_checker (
StableDiffusionSafetyChecker
) — Classification module that estimates whether generated images could be considered offensive or harmful. Please, refer to the model card for details. -
feature_extractor (
CLIPImageProcessor
) — Model that extracts features from generated images to be used as inputs for thesafety_checker
.
Pipeline for text-to-image generation using Stable Diffusion.
This model inherits from DiffusionPipeline. Check the superclass documentation for the generic methods the library implements for all the pipelines (such as downloading or saving, running on a particular device, etc.)
In addition the pipeline inherits the following loading methods:
- Textual-Inversion: loaders.TextualInversionLoaderMixin.load_textual_inversion()
- LoRA: loaders.LoraLoaderMixin.load_lora_weights()
- Ckpt: loaders.FromCkptMixin.from_ckpt()
as well as the following saving methods:
__call__
< source >(
prompt: typing.Union[str, typing.List[str]] = None
height: typing.Optional[int] = None
width: typing.Optional[int] = None
num_inference_steps: int = 50
guidance_scale: float = 7.5
negative_prompt: typing.Union[str, typing.List[str], NoneType] = None
num_images_per_prompt: typing.Optional[int] = 1
eta: float = 0.0
generator: typing.Union[torch._C.Generator, typing.List[torch._C.Generator], NoneType] = None
latents: typing.Optional[torch.FloatTensor] = None
prompt_embeds: typing.Optional[torch.FloatTensor] = None
negative_prompt_embeds: typing.Optional[torch.FloatTensor] = None
output_type: typing.Optional[str] = 'pil'
return_dict: bool = True
callback: typing.Union[typing.Callable[[int, int, torch.FloatTensor], NoneType], NoneType] = None
callback_steps: int = 1
cross_attention_kwargs: typing.Union[typing.Dict[str, typing.Any], NoneType] = None
)
→
StableDiffusionPipelineOutput or tuple
Parameters
-
prompt (
str
orList[str]
, optional) — The prompt or prompts to guide the image generation. If not defined, one has to passprompt_embeds
. instead. -
height (
int
, optional, defaults to self.unet.config.sample_size * self.vae_scale_factor) — The height in pixels of the generated image. -
width (
int
, optional, defaults to self.unet.config.sample_size * self.vae_scale_factor) — 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.guidance_scale
is defined asw
of equation 2. of Imagen Paper. Guidance scale is enabled by settingguidance_scale > 1
. Higher guidance scale encourages to generate images that are closely linked to the textprompt
, usually at the expense of lower image quality. -
negative_prompt (
str
orList[str]
, optional) — The prompt or prompts not to guide the image generation. If not defined, one has to passnegative_prompt_embeds
instead. Ignored when not using guidance (i.e., ignored ifguidance_scale
is less than1
). -
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
orList[torch.Generator]
, optional) — One or a list of torch generator(s) 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 randomgenerator
. -
prompt_embeds (
torch.FloatTensor
, optional) — Pre-generated text embeddings. Can be used to easily tweak text inputs, e.g. prompt weighting. If not provided, text embeddings will be generated fromprompt
input argument. -
negative_prompt_embeds (
torch.FloatTensor
, optional) — Pre-generated negative text embeddings. Can be used to easily tweak text inputs, e.g. prompt weighting. If not provided, negative_prompt_embeds will be generated fromnegative_prompt
input argument. -
output_type (
str
, optional, defaults to"pil"
) — The output format of the generate image. Choose between PIL:PIL.Image.Image
ornp.array
. -
return_dict (
bool
, optional, defaults toTrue
) — Whether or not to return a StableDiffusionPipelineOutput instead of a plain tuple. -
callback (
Callable
, optional) — A function that will be called everycallback_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 thecallback
function will be called. If not specified, the callback will be called at every step. -
cross_attention_kwargs (
dict
, optional) — A kwargs dictionary that if specified is passed along to theAttentionProcessor
as defined underself.processor
in diffusers.cross_attention.
Returns
StableDiffusionPipelineOutput or tuple
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
bools denoting whether the corresponding generated image likely represents "not-safe-for-work" (nsfw) content, according to the
safety_checker`.
Function invoked when calling the pipeline for generation.
Examples:
>>> import torch
>>> from diffusers import StableDiffusionPipeline
>>> pipe = StableDiffusionPipeline.from_pretrained("runwayml/stable-diffusion-v1-5", torch_dtype=torch.float16)
>>> pipe = pipe.to("cuda")
>>> prompt = "a photo of an astronaut riding a horse on mars"
>>> image = pipe(prompt).images[0]
enable_attention_slicing
< source >( slice_size: typing.Union[str, int, NoneType] = 'auto' )
Parameters
-
slice_size (
str
orint
, optional, defaults to"auto"
) — When"auto"
, halves the input to the attention heads, so attention will be computed in two steps. If"max"
, maximum amount of memory will be saved by running only one slice at a time. If a number is provided, uses as many slices asattention_head_dim // slice_size
. In this case,attention_head_dim
must be a multiple ofslice_size
.
Enable sliced attention computation.
When this option is enabled, the attention module will split the input tensor in slices, to compute attention in several steps. This is useful to save some memory in exchange for a small speed decrease.
Disable sliced attention computation. If enable_attention_slicing
was previously invoked, this method will go
back to computing attention in one step.
Enable sliced VAE decoding.
When this option is enabled, the VAE will split the input tensor in slices to compute decoding in several steps. This is useful to save some memory and allow larger batch sizes.
Disable sliced VAE decoding. If enable_vae_slicing
was previously invoked, this method will go back to
computing decoding in one step.
enable_xformers_memory_efficient_attention
< source >( attention_op: typing.Optional[typing.Callable] = None )
Parameters
-
attention_op (
Callable
, optional) — Override the defaultNone
operator for use asop
argument to thememory_efficient_attention()
function of xFormers.
Enable memory efficient attention as implemented in xformers.
When this option is enabled, you should observe lower GPU memory usage and a potential speed up at inference time. Speed up at training time is not guaranteed.
Warning: When Memory Efficient Attention and Sliced attention are both enabled, the Memory Efficient Attention is used.
Examples:
>>> import torch
>>> from diffusers import DiffusionPipeline
>>> from xformers.ops import MemoryEfficientAttentionFlashAttentionOp
>>> pipe = DiffusionPipeline.from_pretrained("stabilityai/stable-diffusion-2-1", torch_dtype=torch.float16)
>>> pipe = pipe.to("cuda")
>>> pipe.enable_xformers_memory_efficient_attention(attention_op=MemoryEfficientAttentionFlashAttentionOp)
>>> # Workaround for not accepting attention shape using VAE for Flash Attention
>>> pipe.vae.enable_xformers_memory_efficient_attention(attention_op=None)
Disable memory efficient attention as implemented in xformers.
Enable tiled VAE decoding.
When this option is enabled, the VAE will split the input tensor into tiles to compute decoding and encoding in several steps. This is useful to save a large amount of memory and to allow the processing of larger images.
Disable tiled VAE decoding. If enable_vae_tiling
was previously invoked, this method will go back to
computing decoding in one step.
load_textual_inversion
< source >( pretrained_model_name_or_path: typing.Union[str, typing.Dict[str, torch.Tensor]] token: typing.Optional[str] = None **kwargs )
Parameters
-
pretrained_model_name_or_path (
str
oros.PathLike
) — Can be either:- A string, the model id of a pretrained model hosted inside a model repo on huggingface.co.
Valid model ids should have an organization name, like
"sd-concepts-library/low-poly-hd-logos-icons"
. - A path to a directory containing textual inversion weights, e.g.
./my_text_inversion_directory/
.
- A string, the model id of a pretrained model hosted inside a model repo on huggingface.co.
Valid model ids should have an organization name, like
-
weight_name (
str
, optional) — Name of a custom weight file. This should be used in two cases:- The saved textual inversion file is in
diffusers
format, but was saved under a specific weight name, such astext_inv.bin
. - The saved textual inversion file is in the “Automatic1111” form.
- The saved textual inversion file is in
-
cache_dir (
Union[str, os.PathLike]
, optional) — Path to a directory in which a downloaded pretrained model configuration should be cached if the standard cache should not be used. -
force_download (
bool
, optional, defaults toFalse
) — Whether or not to force the (re-)download of the model weights and configuration files, overriding the cached versions if they exist. -
resume_download (
bool
, optional, defaults toFalse
) — Whether or not to delete incompletely received files. Will attempt to resume the download if such a file exists. -
proxies (
Dict[str, str]
, optional) — A dictionary of proxy servers to use by protocol or endpoint, e.g.,{'http': 'foo.bar:3128', 'http://hostname': 'foo.bar:4012'}
. The proxies are used on each request. -
local_files_only(
bool
, optional, defaults toFalse
) — Whether or not to only look at local files (i.e., do not try to download the model). -
use_auth_token (
str
or bool, optional) — The token to use as HTTP bearer authorization for remote files. IfTrue
, will use the token generated when runningdiffusers-cli login
(stored in~/.huggingface
). -
revision (
str
, optional, defaults to"main"
) — The specific model version to use. It can be a branch name, a tag name, or a commit id, since we use a git-based system for storing models and other artifacts on huggingface.co, sorevision
can be any identifier allowed by git. -
subfolder (
str
, optional, defaults to""
) — In case the relevant files are located inside a subfolder of the model repo (either remote in huggingface.co or downloaded locally), you can specify the folder name here. -
mirror (
str
, optional) — Mirror source to accelerate downloads in China. If you are from China and have an accessibility problem, you can set this option to resolve it. Note that we do not guarantee the timeliness or safety. Please refer to the mirror site for more information.
Load textual inversion embeddings into the text encoder of stable diffusion pipelines. Both diffusers
and
Automatic1111
formats are supported (see example below).
This function is experimental and might change in the future.
It is required to be logged in (huggingface-cli login
) when you want to use private or gated
models.
Example:
To load a textual inversion embedding vector in diffusers
format:
from diffusers import StableDiffusionPipeline
import torch
model_id = "runwayml/stable-diffusion-v1-5"
pipe = StableDiffusionPipeline.from_pretrained(model_id, torch_dtype=torch.float16).to("cuda")
pipe.load_textual_inversion("sd-concepts-library/cat-toy")
prompt = "A <cat-toy> backpack"
image = pipe(prompt, num_inference_steps=50).images[0]
image.save("cat-backpack.png")
To load a textual inversion embedding vector in Automatic1111 format, make sure to first download the vector,
e.g. from civitAI and then load the vector locally:
from diffusers import StableDiffusionPipeline
import torch
model_id = "runwayml/stable-diffusion-v1-5"
pipe = StableDiffusionPipeline.from_pretrained(model_id, torch_dtype=torch.float16).to("cuda")
pipe.load_textual_inversion("./charturnerv2.pt", token="charturnerv2")
prompt = "charturnerv2, multiple views of the same character in the same outfit, a character turnaround of a woman wearing a black jacket and red shirt, best quality, intricate details."
image = pipe(prompt, num_inference_steps=50).images[0]
image.save("character.png")
from_ckpt
< source >( pretrained_model_link_or_path **kwargs )
Parameters
-
pretrained_model_link_or_path (
str
oros.PathLike
, optional) — Can be either:- A link to the .ckpt file on the Hub. Should be in the format
"https://huggingface.co/<repo_id>/blob/main/<path_to_file>"
- A path to a file containing all pipeline weights.
- A link to the .ckpt file on the Hub. Should be in the format
-
torch_dtype (
str
ortorch.dtype
, optional) — Override the defaulttorch.dtype
and load the model under this dtype. If"auto"
is passed the dtype will be automatically derived from the model’s weights. -
force_download (
bool
, optional, defaults toFalse
) — Whether or not to force the (re-)download of the model weights and configuration files, overriding the cached versions if they exist. -
cache_dir (
Union[str, os.PathLike]
, optional) — Path to a directory in which a downloaded pretrained model configuration should be cached if the standard cache should not be used. -
resume_download (
bool
, optional, defaults toFalse
) — Whether or not to delete incompletely received files. Will attempt to resume the download if such a file exists. -
proxies (
Dict[str, str]
, optional) — A dictionary of proxy servers to use by protocol or endpoint, e.g.,{'http': 'foo.bar:3128', 'http://hostname': 'foo.bar:4012'}
. The proxies are used on each request. -
local_files_only (
bool
, optional, defaults toFalse
) — Whether or not to only look at local files (i.e., do not try to download the model). -
use_auth_token (
str
or bool, optional) — The token to use as HTTP bearer authorization for remote files. IfTrue
, will use the token generated when runninghuggingface-cli login
(stored in~/.huggingface
). -
revision (
str
, optional, defaults to"main"
) — The specific model version to use. It can be a branch name, a tag name, or a commit id, since we use a git-based system for storing models and other artifacts on huggingface.co, sorevision
can be any identifier allowed by git. -
use_safetensors (
bool
, optional ) — If set toTrue
, the pipeline will be loaded fromsafetensors
weights. If set toNone
(the default). The pipeline will load usingsafetensors
if the safetensors weights are available and ifsafetensors
is installed. If the toFalse
the pipeline will not usesafetensors
. -
extract_ema (
bool
, optional, defaults toFalse
) — Only relevant for checkpoints that have both EMA and non-EMA weights. Whether to extract the EMA weights or not. Defaults toFalse
. PassTrue
to extract the EMA weights. EMA weights usually yield higher quality images for inference. Non-EMA weights are usually better to continue fine-tuning. -
upcast_attention (
bool
, optional, defaults toNone
) — Whether the attention computation should always be upcasted. This is necessary when running stable -
image_size (
int
, optional, defaults to 512) — The image size that the model was trained on. Use 512 for Stable Diffusion v1.X and Stable Diffusion v2 Base. Use 768 for Stable Diffusion v2. -
prediction_type (
str
, optional) — The prediction type that the model was trained on. Use'epsilon'
for Stable Diffusion v1.X and Stable Diffusion v2 Base. Use'v_prediction'
for Stable Diffusion v2. -
num_in_channels (
int
, optional, defaults to None) — The number of input channels. IfNone
, it will be automatically inferred. -
scheduler_type (
str
, optional, defaults to ‘pndm’) — Type of scheduler to use. Should be one of["pndm", "lms", "heun", "euler", "euler-ancestral", "dpm", "ddim"]
. -
load_safety_checker (
bool
, optional, defaults toTrue
) — Whether to load the safety checker or not. Defaults toTrue
. -
kwargs (remaining dictionary of keyword arguments, optional) —
Can be used to overwrite load - and saveable variables - i.e. the pipeline components - of the
specific pipeline class. The overwritten components are then directly passed to the pipelines
__init__
method. See example below for more information.
Instantiate a PyTorch diffusion pipeline from pre-trained pipeline weights saved in the original .ckpt format.
The pipeline is set in evaluation mode by default using model.eval()
(Dropout modules are deactivated).
Examples:
>>> from diffusers import StableDiffusionPipeline
>>> # Download pipeline from huggingface.co and cache.
>>> pipeline = StableDiffusionPipeline.from_ckpt(
... "https://huggingface.co/WarriorMama777/OrangeMixs/blob/main/Models/AbyssOrangeMix/AbyssOrangeMix.safetensors"
... )
>>> # Download pipeline from local file
>>> # file is downloaded under ./v1-5-pruned-emaonly.ckpt
>>> pipeline = StableDiffusionPipeline.from_ckpt("./v1-5-pruned-emaonly")
>>> # Enable float16 and move to GPU
>>> pipeline = StableDiffusionPipeline.from_ckpt(
... "https://huggingface.co/runwayml/stable-diffusion-v1-5/blob/main/v1-5-pruned-emaonly.ckpt",
... torch_dtype=torch.float16,
... )
>>> pipeline.to("cuda")
load_lora_weights
< source >( pretrained_model_name_or_path_or_dict: typing.Union[str, typing.Dict[str, torch.Tensor]] **kwargs )
Parameters
-
pretrained_model_name_or_path_or_dict (
str
oros.PathLike
ordict
) — Can be either:- A string, the model id of a pretrained model hosted inside a model repo on huggingface.co.
Valid model ids should have an organization name, like
google/ddpm-celebahq-256
. - A path to a directory containing model weights saved using
~ModelMixin.save_config
, e.g.,./my_model_directory/
. - A torch state dict.
- A string, the model id of a pretrained model hosted inside a model repo on huggingface.co.
Valid model ids should have an organization name, like
-
cache_dir (
Union[str, os.PathLike]
, optional) — Path to a directory in which a downloaded pretrained model configuration should be cached if the standard cache should not be used. -
force_download (
bool
, optional, defaults toFalse
) — Whether or not to force the (re-)download of the model weights and configuration files, overriding the cached versions if they exist. -
resume_download (
bool
, optional, defaults toFalse
) — Whether or not to delete incompletely received files. Will attempt to resume the download if such a file exists. -
proxies (
Dict[str, str]
, optional) — A dictionary of proxy servers to use by protocol or endpoint, e.g.,{'http': 'foo.bar:3128', 'http://hostname': 'foo.bar:4012'}
. The proxies are used on each request. -
local_files_only(
bool
, optional, defaults toFalse
) — Whether or not to only look at local files (i.e., do not try to download the model). -
use_auth_token (
str
or bool, optional) — The token to use as HTTP bearer authorization for remote files. IfTrue
, will use the token generated when runningdiffusers-cli login
(stored in~/.huggingface
). -
revision (
str
, optional, defaults to"main"
) — The specific model version to use. It can be a branch name, a tag name, or a commit id, since we use a git-based system for storing models and other artifacts on huggingface.co, sorevision
can be any identifier allowed by git. -
subfolder (
str
, optional, defaults to""
) — In case the relevant files are located inside a subfolder of the model repo (either remote in huggingface.co or downloaded locally), you can specify the folder name here. -
mirror (
str
, optional) — Mirror source to accelerate downloads in China. If you are from China and have an accessibility problem, you can set this option to resolve it. Note that we do not guarantee the timeliness or safety. Please refer to the mirror site for more information.
Load pretrained attention processor layers (such as LoRA) into UNet2DConditionModel and
CLIPTextModel
).
This function is experimental and might change in the future.
It is required to be logged in (huggingface-cli login
) when you want to use private or gated
models.
save_lora_weights
< source >( save_directory: typing.Union[str, os.PathLike] unet_lora_layers: typing.Dict[str, torch.nn.modules.module.Module] = None text_encoder_lora_layers: typing.Dict[str, torch.nn.modules.module.Module] = None is_main_process: bool = True weight_name: str = None save_function: typing.Callable = None safe_serialization: bool = False )
Parameters
-
save_directory (
str
oros.PathLike
) — Directory to which to save. Will be created if it doesn’t exist. -
unet_lora_layers (
Dict[str, torch.nn.Module
]) — State dict of the LoRA layers corresponding to the UNet. Specifying this helps to make the serialization process easier and cleaner. -
text_encoder_lora_layers (
Dict[str, torch.nn.Module
]) — State dict of the LoRA layers corresponding to thetext_encoder
. Since thetext_encoder
comes fromtransformers
, we cannot rejig it. That is why we have to explicitly pass the text encoder LoRA state dict. -
is_main_process (
bool
, optional, defaults toTrue
) — Whether the process calling this is the main process or not. Useful when in distributed training like TPUs and need to call this function on all processes. In this case, setis_main_process=True
only on the main process to avoid race conditions. -
save_function (
Callable
) — The function to use to save the state dictionary. Useful on distributed training like TPUs when one need to replacetorch.save
by another method. Can be configured with the environment variableDIFFUSERS_SAVE_MODE
.
Save the LoRA parameters corresponding to the UNet and the text encoder.
Offloads all models to CPU using accelerate, reducing memory usage with a low impact on performance. Compared
to enable_sequential_cpu_offload
, this method moves one whole model at a time to the GPU when its forward
method is called, and the model remains in GPU until the next model runs. Memory savings are lower than with
enable_sequential_cpu_offload
, but performance is much better due to the iterative execution of the unet
.
Offloads all models to CPU using accelerate, significantly reducing memory usage. When called, unet,
text_encoder, vae and safety checker have their state dicts saved to CPU and then are moved to a
torch.device('meta') and loaded to GPU only when their specific submodule has its
forwardmethod called. Note that offloading happens on a submodule basis. Memory savings are higher than with
enable_model_cpu_offload`, but performance is lower.
class diffusers.FlaxStableDiffusionPipeline
< source >( vae: FlaxAutoencoderKL text_encoder: FlaxCLIPTextModel tokenizer: CLIPTokenizer unet: FlaxUNet2DConditionModel scheduler: typing.Union[diffusers.schedulers.scheduling_ddim_flax.FlaxDDIMScheduler, diffusers.schedulers.scheduling_pndm_flax.FlaxPNDMScheduler, diffusers.schedulers.scheduling_lms_discrete_flax.FlaxLMSDiscreteScheduler, diffusers.schedulers.scheduling_dpmsolver_multistep_flax.FlaxDPMSolverMultistepScheduler] safety_checker: FlaxStableDiffusionSafetyChecker feature_extractor: CLIPImageProcessor dtype: dtype = <class 'jax.numpy.float32'> )
Parameters
- vae (FlaxAutoencoderKL) — Variational Auto-Encoder (VAE) Model to encode and decode images to and from latent representations.
-
text_encoder (
FlaxCLIPTextModel
) — Frozen text-encoder. Stable Diffusion uses the text portion of CLIP, specifically the clip-vit-large-patch14 variant. -
tokenizer (
CLIPTokenizer
) — Tokenizer of class CLIPTokenizer. - unet (FlaxUNet2DConditionModel) — Conditional U-Net architecture to denoise the encoded image latents.
-
scheduler (SchedulerMixin) —
A scheduler to be used in combination with
unet
to denoise the encoded image latents. Can be one ofFlaxDDIMScheduler
,FlaxLMSDiscreteScheduler
,FlaxPNDMScheduler
, orFlaxDPMSolverMultistepScheduler
. -
safety_checker (
FlaxStableDiffusionSafetyChecker
) — Classification module that estimates whether generated images could be considered offensive or harmful. Please, refer to the model card for details. -
feature_extractor (
CLIPImageProcessor
) — Model that extracts features from generated images to be used as inputs for thesafety_checker
.
Pipeline for text-to-image generation using Stable Diffusion.
This model inherits from FlaxDiffusionPipeline
. Check the superclass documentation for the generic methods the
library implements for all the pipelines (such as downloading or saving, running on a particular device, etc.)
__call__
< source >(
prompt_ids: array
params: typing.Union[typing.Dict, flax.core.frozen_dict.FrozenDict]
prng_seed: PRNGKeyArray
num_inference_steps: int = 50
height: typing.Optional[int] = None
width: typing.Optional[int] = None
guidance_scale: typing.Union[float, array] = 7.5
latents: array = None
neg_prompt_ids: array = None
return_dict: bool = True
jit: bool = False
)
→
FlaxStableDiffusionPipelineOutput
or tuple
Parameters
-
prompt (
str
orList[str]
) — The prompt or prompts to guide the image generation. -
height (
int
, optional, defaults to self.unet.config.sample_size * self.vae_scale_factor) — The height in pixels of the generated image. -
width (
int
, optional, defaults to self.unet.config.sample_size * self.vae_scale_factor) — 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.guidance_scale
is defined asw
of equation 2. of Imagen Paper. Guidance scale is enabled by settingguidance_scale > 1
. Higher guidance scale encourages to generate images that are closely linked to the textprompt
, usually at the expense of lower image quality. -
latents (
jnp.array
, 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. tensor will ge generated by sampling using the supplied randomgenerator
. -
jit (
bool
, defaults toFalse
) — Whether to runpmap
versions of the generation and safety scoring functions. NOTE: This argument exists because__call__
is not yet end-to-end pmap-able. It will be removed in a future release. -
return_dict (
bool
, optional, defaults toTrue
) — Whether or not to return aFlaxStableDiffusionPipelineOutput
instead of a plain tuple.
Returns
FlaxStableDiffusionPipelineOutput
or tuple
FlaxStableDiffusionPipelineOutput
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
bools denoting whether the corresponding generated image likely represents "not-safe-for-work" (nsfw) content, according to the
safety_checker`.
Function invoked when calling the pipeline for generation.
Examples:
>>> import jax
>>> import numpy as np
>>> from flax.jax_utils import replicate
>>> from flax.training.common_utils import shard
>>> from diffusers import FlaxStableDiffusionPipeline
>>> pipeline, params = FlaxStableDiffusionPipeline.from_pretrained(
... "runwayml/stable-diffusion-v1-5", revision="bf16", dtype=jax.numpy.bfloat16
... )
>>> prompt = "a photo of an astronaut riding a horse on mars"
>>> prng_seed = jax.random.PRNGKey(0)
>>> num_inference_steps = 50
>>> num_samples = jax.device_count()
>>> prompt = num_samples * [prompt]
>>> prompt_ids = pipeline.prepare_inputs(prompt)
# shard inputs and rng
>>> params = replicate(params)
>>> prng_seed = jax.random.split(prng_seed, jax.device_count())
>>> prompt_ids = shard(prompt_ids)
>>> images = pipeline(prompt_ids, params, prng_seed, num_inference_steps, jit=True).images
>>> images = pipeline.numpy_to_pil(np.asarray(images.reshape((num_samples,) + images.shape[-3:])))