Datasets:

ArXiv:
community-pipelines-mirror / v0.25.1 /clip_guided_images_mixing_stable_diffusion.py
Diffusers Bot
Upload folder using huggingface_hub
727e6af verified
raw
history blame
19.7 kB
# -*- coding: utf-8 -*-
import inspect
from typing import Optional, Union
import numpy as np
import PIL.Image
import torch
from torch.nn import functional as F
from torchvision import transforms
from transformers import CLIPFeatureExtractor, CLIPModel, CLIPTextModel, CLIPTokenizer
from diffusers import (
AutoencoderKL,
DDIMScheduler,
DiffusionPipeline,
DPMSolverMultistepScheduler,
LMSDiscreteScheduler,
PNDMScheduler,
UNet2DConditionModel,
)
from diffusers.pipelines.stable_diffusion.pipeline_stable_diffusion import StableDiffusionPipelineOutput
from diffusers.utils import PIL_INTERPOLATION
from diffusers.utils.torch_utils import randn_tensor
def preprocess(image, w, h):
if isinstance(image, torch.Tensor):
return image
elif isinstance(image, PIL.Image.Image):
image = [image]
if isinstance(image[0], PIL.Image.Image):
image = [np.array(i.resize((w, h), resample=PIL_INTERPOLATION["lanczos"]))[None, :] for i in image]
image = np.concatenate(image, axis=0)
image = np.array(image).astype(np.float32) / 255.0
image = image.transpose(0, 3, 1, 2)
image = 2.0 * image - 1.0
image = torch.from_numpy(image)
elif isinstance(image[0], torch.Tensor):
image = torch.cat(image, dim=0)
return image
def slerp(t, v0, v1, DOT_THRESHOLD=0.9995):
if not isinstance(v0, np.ndarray):
inputs_are_torch = True
input_device = v0.device
v0 = v0.cpu().numpy()
v1 = v1.cpu().numpy()
dot = np.sum(v0 * v1 / (np.linalg.norm(v0) * np.linalg.norm(v1)))
if np.abs(dot) > DOT_THRESHOLD:
v2 = (1 - t) * v0 + t * v1
else:
theta_0 = np.arccos(dot)
sin_theta_0 = np.sin(theta_0)
theta_t = theta_0 * t
sin_theta_t = np.sin(theta_t)
s0 = np.sin(theta_0 - theta_t) / sin_theta_0
s1 = sin_theta_t / sin_theta_0
v2 = s0 * v0 + s1 * v1
if inputs_are_torch:
v2 = torch.from_numpy(v2).to(input_device)
return v2
def spherical_dist_loss(x, y):
x = F.normalize(x, dim=-1)
y = F.normalize(y, dim=-1)
return (x - y).norm(dim=-1).div(2).arcsin().pow(2).mul(2)
def set_requires_grad(model, value):
for param in model.parameters():
param.requires_grad = value
class CLIPGuidedImagesMixingStableDiffusion(DiffusionPipeline):
def __init__(
self,
vae: AutoencoderKL,
text_encoder: CLIPTextModel,
clip_model: CLIPModel,
tokenizer: CLIPTokenizer,
unet: UNet2DConditionModel,
scheduler: Union[PNDMScheduler, LMSDiscreteScheduler, DDIMScheduler, DPMSolverMultistepScheduler],
feature_extractor: CLIPFeatureExtractor,
coca_model=None,
coca_tokenizer=None,
coca_transform=None,
):
super().__init__()
self.register_modules(
vae=vae,
text_encoder=text_encoder,
clip_model=clip_model,
tokenizer=tokenizer,
unet=unet,
scheduler=scheduler,
feature_extractor=feature_extractor,
coca_model=coca_model,
coca_tokenizer=coca_tokenizer,
coca_transform=coca_transform,
)
self.feature_extractor_size = (
feature_extractor.size
if isinstance(feature_extractor.size, int)
else feature_extractor.size["shortest_edge"]
)
self.normalize = transforms.Normalize(mean=feature_extractor.image_mean, std=feature_extractor.image_std)
set_requires_grad(self.text_encoder, False)
set_requires_grad(self.clip_model, False)
def enable_attention_slicing(self, slice_size: Optional[Union[str, int]] = "auto"):
if slice_size == "auto":
# half the attention head size is usually a good trade-off between
# speed and memory
slice_size = self.unet.config.attention_head_dim // 2
self.unet.set_attention_slice(slice_size)
def disable_attention_slicing(self):
self.enable_attention_slicing(None)
def freeze_vae(self):
set_requires_grad(self.vae, False)
def unfreeze_vae(self):
set_requires_grad(self.vae, True)
def freeze_unet(self):
set_requires_grad(self.unet, False)
def unfreeze_unet(self):
set_requires_grad(self.unet, True)
def get_timesteps(self, num_inference_steps, strength, device):
# get the original timestep using init_timestep
init_timestep = min(int(num_inference_steps * strength), num_inference_steps)
t_start = max(num_inference_steps - init_timestep, 0)
timesteps = self.scheduler.timesteps[t_start:]
return timesteps, num_inference_steps - t_start
def prepare_latents(self, image, timestep, batch_size, dtype, device, generator=None):
if not isinstance(image, torch.Tensor):
raise ValueError(f"`image` has to be of type `torch.Tensor` but is {type(image)}")
image = image.to(device=device, dtype=dtype)
if isinstance(generator, list):
init_latents = [
self.vae.encode(image[i : i + 1]).latent_dist.sample(generator[i]) for i in range(batch_size)
]
init_latents = torch.cat(init_latents, dim=0)
else:
init_latents = self.vae.encode(image).latent_dist.sample(generator)
# Hardcode 0.18215 because stable-diffusion-2-base has not self.vae.config.scaling_factor
init_latents = 0.18215 * init_latents
init_latents = init_latents.repeat_interleave(batch_size, dim=0)
noise = randn_tensor(init_latents.shape, generator=generator, device=device, dtype=dtype)
# get latents
init_latents = self.scheduler.add_noise(init_latents, noise, timestep)
latents = init_latents
return latents
def get_image_description(self, image):
transformed_image = self.coca_transform(image).unsqueeze(0)
with torch.no_grad(), torch.cuda.amp.autocast():
generated = self.coca_model.generate(transformed_image.to(device=self.device, dtype=self.coca_model.dtype))
generated = self.coca_tokenizer.decode(generated[0].cpu().numpy())
return generated.split("<end_of_text>")[0].replace("<start_of_text>", "").rstrip(" .,")
def get_clip_image_embeddings(self, image, batch_size):
clip_image_input = self.feature_extractor.preprocess(image)
clip_image_features = torch.from_numpy(clip_image_input["pixel_values"][0]).unsqueeze(0).to(self.device).half()
image_embeddings_clip = self.clip_model.get_image_features(clip_image_features)
image_embeddings_clip = image_embeddings_clip / image_embeddings_clip.norm(p=2, dim=-1, keepdim=True)
image_embeddings_clip = image_embeddings_clip.repeat_interleave(batch_size, dim=0)
return image_embeddings_clip
@torch.enable_grad()
def cond_fn(
self,
latents,
timestep,
index,
text_embeddings,
noise_pred_original,
original_image_embeddings_clip,
clip_guidance_scale,
):
latents = latents.detach().requires_grad_()
latent_model_input = self.scheduler.scale_model_input(latents, timestep)
# predict the noise residual
noise_pred = self.unet(latent_model_input, timestep, encoder_hidden_states=text_embeddings).sample
if isinstance(self.scheduler, (PNDMScheduler, DDIMScheduler, DPMSolverMultistepScheduler)):
alpha_prod_t = self.scheduler.alphas_cumprod[timestep]
beta_prod_t = 1 - alpha_prod_t
# compute predicted original sample from predicted noise also called
# "predicted x_0" of formula (12) from https://arxiv.org/pdf/2010.02502.pdf
pred_original_sample = (latents - beta_prod_t ** (0.5) * noise_pred) / alpha_prod_t ** (0.5)
fac = torch.sqrt(beta_prod_t)
sample = pred_original_sample * (fac) + latents * (1 - fac)
elif isinstance(self.scheduler, LMSDiscreteScheduler):
sigma = self.scheduler.sigmas[index]
sample = latents - sigma * noise_pred
else:
raise ValueError(f"scheduler type {type(self.scheduler)} not supported")
# Hardcode 0.18215 because stable-diffusion-2-base has not self.vae.config.scaling_factor
sample = 1 / 0.18215 * sample
image = self.vae.decode(sample).sample
image = (image / 2 + 0.5).clamp(0, 1)
image = transforms.Resize(self.feature_extractor_size)(image)
image = self.normalize(image).to(latents.dtype)
image_embeddings_clip = self.clip_model.get_image_features(image)
image_embeddings_clip = image_embeddings_clip / image_embeddings_clip.norm(p=2, dim=-1, keepdim=True)
loss = spherical_dist_loss(image_embeddings_clip, original_image_embeddings_clip).mean() * clip_guidance_scale
grads = -torch.autograd.grad(loss, latents)[0]
if isinstance(self.scheduler, LMSDiscreteScheduler):
latents = latents.detach() + grads * (sigma**2)
noise_pred = noise_pred_original
else:
noise_pred = noise_pred_original - torch.sqrt(beta_prod_t) * grads
return noise_pred, latents
@torch.no_grad()
def __call__(
self,
style_image: Union[torch.FloatTensor, PIL.Image.Image],
content_image: Union[torch.FloatTensor, PIL.Image.Image],
style_prompt: Optional[str] = None,
content_prompt: Optional[str] = None,
height: Optional[int] = 512,
width: Optional[int] = 512,
noise_strength: float = 0.6,
num_inference_steps: Optional[int] = 50,
guidance_scale: Optional[float] = 7.5,
batch_size: Optional[int] = 1,
eta: float = 0.0,
clip_guidance_scale: Optional[float] = 100,
generator: Optional[torch.Generator] = None,
output_type: Optional[str] = "pil",
return_dict: bool = True,
slerp_latent_style_strength: float = 0.8,
slerp_prompt_style_strength: float = 0.1,
slerp_clip_image_style_strength: float = 0.1,
):
if isinstance(generator, list) and len(generator) != batch_size:
raise ValueError(f"You have passed {batch_size} batch_size, but only {len(generator)} generators.")
if height % 8 != 0 or width % 8 != 0:
raise ValueError(f"`height` and `width` have to be divisible by 8 but are {height} and {width}.")
if isinstance(generator, torch.Generator) and batch_size > 1:
generator = [generator] + [None] * (batch_size - 1)
coca_is_none = [
("model", self.coca_model is None),
("tokenizer", self.coca_tokenizer is None),
("transform", self.coca_transform is None),
]
coca_is_none = [x[0] for x in coca_is_none if x[1]]
coca_is_none_str = ", ".join(coca_is_none)
# generate prompts with coca model if prompt is None
if content_prompt is None:
if len(coca_is_none):
raise ValueError(
f"Content prompt is None and CoCa [{coca_is_none_str}] is None."
f"Set prompt or pass Coca [{coca_is_none_str}] to DiffusionPipeline."
)
content_prompt = self.get_image_description(content_image)
if style_prompt is None:
if len(coca_is_none):
raise ValueError(
f"Style prompt is None and CoCa [{coca_is_none_str}] is None."
f" Set prompt or pass Coca [{coca_is_none_str}] to DiffusionPipeline."
)
style_prompt = self.get_image_description(style_image)
# get prompt text embeddings for content and style
content_text_input = self.tokenizer(
content_prompt,
padding="max_length",
max_length=self.tokenizer.model_max_length,
truncation=True,
return_tensors="pt",
)
content_text_embeddings = self.text_encoder(content_text_input.input_ids.to(self.device))[0]
style_text_input = self.tokenizer(
style_prompt,
padding="max_length",
max_length=self.tokenizer.model_max_length,
truncation=True,
return_tensors="pt",
)
style_text_embeddings = self.text_encoder(style_text_input.input_ids.to(self.device))[0]
text_embeddings = slerp(slerp_prompt_style_strength, content_text_embeddings, style_text_embeddings)
# duplicate text embeddings for each generation per prompt
text_embeddings = text_embeddings.repeat_interleave(batch_size, dim=0)
# set timesteps
accepts_offset = "offset" in set(inspect.signature(self.scheduler.set_timesteps).parameters.keys())
extra_set_kwargs = {}
if accepts_offset:
extra_set_kwargs["offset"] = 1
self.scheduler.set_timesteps(num_inference_steps, **extra_set_kwargs)
# Some schedulers like PNDM have timesteps as arrays
# It's more optimized to move all timesteps to correct device beforehand
self.scheduler.timesteps.to(self.device)
timesteps, num_inference_steps = self.get_timesteps(num_inference_steps, noise_strength, self.device)
latent_timestep = timesteps[:1].repeat(batch_size)
# Preprocess image
preprocessed_content_image = preprocess(content_image, width, height)
content_latents = self.prepare_latents(
preprocessed_content_image, latent_timestep, batch_size, text_embeddings.dtype, self.device, generator
)
preprocessed_style_image = preprocess(style_image, width, height)
style_latents = self.prepare_latents(
preprocessed_style_image, latent_timestep, batch_size, text_embeddings.dtype, self.device, generator
)
latents = slerp(slerp_latent_style_strength, content_latents, style_latents)
if clip_guidance_scale > 0:
content_clip_image_embedding = self.get_clip_image_embeddings(content_image, batch_size)
style_clip_image_embedding = self.get_clip_image_embeddings(style_image, batch_size)
clip_image_embeddings = slerp(
slerp_clip_image_style_strength, content_clip_image_embedding, style_clip_image_embedding
)
# 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 = guidance_scale > 1.0
# get unconditional embeddings for classifier free guidance
if do_classifier_free_guidance:
max_length = content_text_input.input_ids.shape[-1]
uncond_input = self.tokenizer([""], padding="max_length", max_length=max_length, return_tensors="pt")
uncond_embeddings = self.text_encoder(uncond_input.input_ids.to(self.device))[0]
# duplicate unconditional embeddings for each generation per prompt
uncond_embeddings = uncond_embeddings.repeat_interleave(batch_size, dim=0)
# For classifier free guidance, we need to do two forward passes.
# Here we concatenate the unconditional and text embeddings into a single batch
# to avoid doing two forward passes
text_embeddings = torch.cat([uncond_embeddings, text_embeddings])
# get the initial random noise unless the user supplied it
# Unlike in other pipelines, latents need to be generated in the target device
# for 1-to-1 results reproducibility with the CompVis implementation.
# However this currently doesn't work in `mps`.
latents_shape = (batch_size, self.unet.config.in_channels, height // 8, width // 8)
latents_dtype = text_embeddings.dtype
if latents is None:
if self.device.type == "mps":
# randn does not work reproducibly on mps
latents = torch.randn(latents_shape, generator=generator, device="cpu", dtype=latents_dtype).to(
self.device
)
else:
latents = torch.randn(latents_shape, generator=generator, device=self.device, dtype=latents_dtype)
else:
if latents.shape != latents_shape:
raise ValueError(f"Unexpected latents shape, got {latents.shape}, expected {latents_shape}")
latents = latents.to(self.device)
# scale the initial noise by the standard deviation required by the scheduler
latents = latents * self.scheduler.init_noise_sigma
# prepare extra kwargs for the scheduler step, since not all schedulers have the same signature
# eta (η) is only used with the DDIMScheduler, it will be ignored for other schedulers.
# eta corresponds to η in DDIM paper: https://arxiv.org/abs/2010.02502
# and should be between [0, 1]
accepts_eta = "eta" in set(inspect.signature(self.scheduler.step).parameters.keys())
extra_step_kwargs = {}
if accepts_eta:
extra_step_kwargs["eta"] = eta
# check if the scheduler accepts generator
accepts_generator = "generator" in set(inspect.signature(self.scheduler.step).parameters.keys())
if accepts_generator:
extra_step_kwargs["generator"] = generator
with self.progress_bar(total=num_inference_steps) as progress_bar:
for i, t in enumerate(timesteps):
# expand the latents if we are doing classifier free guidance
latent_model_input = torch.cat([latents] * 2) if do_classifier_free_guidance else latents
latent_model_input = self.scheduler.scale_model_input(latent_model_input, t)
# predict the noise residual
noise_pred = self.unet(latent_model_input, t, encoder_hidden_states=text_embeddings).sample
# perform classifier free guidance
if do_classifier_free_guidance:
noise_pred_uncond, noise_pred_text = noise_pred.chunk(2)
noise_pred = noise_pred_uncond + guidance_scale * (noise_pred_text - noise_pred_uncond)
# perform clip guidance
if clip_guidance_scale > 0:
text_embeddings_for_guidance = (
text_embeddings.chunk(2)[1] if do_classifier_free_guidance else text_embeddings
)
noise_pred, latents = self.cond_fn(
latents,
t,
i,
text_embeddings_for_guidance,
noise_pred,
clip_image_embeddings,
clip_guidance_scale,
)
# compute the previous noisy sample x_t -> x_t-1
latents = self.scheduler.step(noise_pred, t, latents, **extra_step_kwargs).prev_sample
progress_bar.update()
# Hardcode 0.18215 because stable-diffusion-2-base has not self.vae.config.scaling_factor
latents = 1 / 0.18215 * latents
image = self.vae.decode(latents).sample
image = (image / 2 + 0.5).clamp(0, 1)
image = image.cpu().permute(0, 2, 3, 1).numpy()
if output_type == "pil":
image = self.numpy_to_pil(image)
if not return_dict:
return (image, None)
return StableDiffusionPipelineOutput(images=image, nsfw_content_detected=None)