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from copy import deepcopy
from dataclasses import dataclass
from diffusers import StableDiffusionXLPipeline
from diffusers.image_processor import PipelineImageInput
from diffusers.pipelines.stable_diffusion_xl.pipeline_stable_diffusion_xl_img2img\
import rescale_noise_cfg, retrieve_latents, retrieve_timesteps
from diffusers.utils import BaseOutput
from diffusers.utils.torch_utils import randn_tensor
import numpy as np
from PIL import Image
import torch
from typing import Any, Callable, Dict, List, Optional, Tuple, Union
from utils.utils import batch_dict_to_tensor, batch_tensor_to_dict, noise_prev, noise_t2t
from utils.sdxl import register_attr
###
# Code from genforce/ctrl-x/ctrl_x/pipelines/pipeline_sdxl.py
BATCH_ORDER = [
"structure_uncond", "appearance_uncond", "uncond", "structure_cond", "appearance_cond", "cond",
]
def get_last_control_i(control_schedule, num_inference_steps):
if control_schedule is None:
return num_inference_steps, num_inference_steps
def max_(l):
if len(l) == 0:
return 0.0
return max(l)
structure_max = 0.0
appearance_max = 0.0
for block in control_schedule.values():
if isinstance(block, list): # Handling mid_block
block = {0: block}
for layer in block.values():
structure_max = max(structure_max, max_(layer[0] + layer[1]))
appearance_max = max(appearance_max, max_(layer[2]))
structure_i = round(num_inference_steps * structure_max)
appearance_i = round(num_inference_steps * appearance_max)
return structure_i, appearance_i
@dataclass
class CtrlXStableDiffusionXLPipelineOutput(BaseOutput):
images: Union[List[Image.Image], np.ndarray]
structures = Union[List[Image.Image], np.ndarray]
appearances = Union[List[Image.Image], np.ndarray]
class CtrlXStableDiffusionXLPipeline(StableDiffusionXLPipeline):
def __call__(
self,
prompt: Union[str, List[str]] = None, # TODO: Support prompt_2 and negative_prompt_2
structure_prompt: Optional[Union[str, List[str]]] = None,
appearance_prompt: Optional[Union[str, List[str]]] = None,
structure_image: Optional[PipelineImageInput] = None,
appearance_image: Optional[PipelineImageInput] = None,
num_inference_steps: int = 50,
timesteps: List[int] = None,
negative_prompt: Optional[Union[str, List[str]]] = None,
positive_prompt: Optional[Union[str, List[str]]] = None,
height: Optional[int] = None,
width: Optional[int] = None,
guidance_scale: float = 5.0,
structure_guidance_scale: Optional[float] = None,
appearance_guidance_scale: Optional[float] = None,
num_images_per_prompt: Optional[int] = 1,
eta: float = 0.0,
generator: Optional[Union[torch.Generator, List[torch.Generator]]] = None,
latents: Optional[torch.Tensor] = None,
structure_latents: Optional[torch.Tensor] = None,
appearance_latents: Optional[torch.Tensor] = None,
prompt_embeds: Optional[torch.Tensor] = None, # Positive prompt is concatenated with prompt, so no embeddings
structure_prompt_embeds: Optional[torch.Tensor] = None,
appearance_prompt_embeds: Optional[torch.Tensor] = None,
negative_prompt_embeds: Optional[torch.Tensor] = None,
pooled_prompt_embeds: Optional[torch.Tensor] = None,
structure_pooled_prompt_embeds: Optional[torch.Tensor] = None,
appearance_pooled_prompt_embeds: Optional[torch.Tensor] = None,
negative_pooled_prompt_embeds: Optional[torch.Tensor] = None,
control_schedule: Optional[Dict] = None,
self_recurrence_schedule: Optional[List[int]] = [], # Format: [(start, end, num_repeat)]
decode_structure: Optional[bool] = True,
decode_appearance: Optional[bool] = True,
output_type: Optional[str] = "pil",
return_dict: bool = True,
cross_attention_kwargs: Optional[Dict[str, Any]] = None,
guidance_rescale: float = 0.0,
original_size: Tuple[int, int] = None,
crops_coords_top_left: Tuple[int, int] = (0, 0),
target_size: Tuple[int, int] = None,
clip_skip: Optional[int] = None,
callback_on_step_end: Optional[Callable[[int, int, Dict], None]] = None,
callback_on_step_end_tensor_inputs: List[str] = ["latents"],
**kwargs,
):
callback = kwargs.pop("callback", None)
callback_steps = kwargs.pop("callback_steps", None)
self._guidance_scale = guidance_scale
# 0. Default height and width to U-Net
height = height or self.default_sample_size * self.vae_scale_factor
width = width or self.default_sample_size * self.vae_scale_factor
original_size = original_size or (height, width)
target_size = target_size or (height, width)
# 2. Set batch_size = 1 as per instruction
batch_size = 1
if isinstance(prompt, list):
assert len(prompt) == batch_size
if prompt_embeds is not None:
assert prompt_embeds.shape[0] == batch_size
device = self._execution_device
# 3. Encode input prompt
text_encoder_lora_scale = (
cross_attention_kwargs.get("scale", None)
if cross_attention_kwargs is not None else None
)
# 3-3.2 Encode input, structure, appearance prompt
# bc98db93-468b-4511-b30d-3a330eca9968
# Prepare prompt data
prompts = [
(prompt, None, None, None, None, prompt_embeds, negative_prompt_embeds, pooled_prompt_embeds, negative_pooled_prompt_embeds),
(structure_prompt, structure_prompt_embeds, negative_prompt if structure_image is None else "", None, None, structure_prompt_embeds, None, structure_pooled_prompt_embeds, None),
(appearance_prompt, appearance_prompt_embeds, negative_prompt if appearance_image is None else "", None, None, appearance_prompt_embeds, None, appearance_pooled_prompt_embeds, None)
]
prompt_embeds_list = []
add_text_embeds_list = []
for item in prompts:
prompt_text, prompt_embeds_temp, negative_prompt_temp, pooled_prompt_embeds_temp = item[:4] # Unpack relevant items
if prompt_text is not None and prompt_text != "":
(
prompt_embeds_,
negative_prompt_embeds,
pooled_prompt_embeds_,
negative_pooled_prompt_embeds,
) = self.encode_prompt(
prompt=prompt_text,
prompt_2=None,
device=device,
num_images_per_prompt=num_images_per_prompt,
do_classifier_free_guidance=True,
negative_prompt=negative_prompt_temp,
negative_prompt_2=None,
prompt_embeds=prompt_embeds_temp,
negative_prompt_embeds=None,
pooled_prompt_embeds=pooled_prompt_embeds_temp,
negative_pooled_prompt_embeds=None,
lora_scale=text_encoder_lora_scale,
clip_skip=clip_skip,
)
prompt_embeds_list.append(torch.cat([negative_prompt_embeds, prompt_embeds_], dim=0).to(device))
add_text_embeds_list.append(torch.cat([negative_pooled_prompt_embeds, pooled_prompt_embeds_], dim=0).to(device))
else:
prompt_embeds_list.append(prompt_embeds_list[0])
add_text_embeds_list.append(add_text_embeds_list[0])
# prompt_embeds, structure_prompt_embeds, appearance_prompt_embeds = prompt_embeds_list
# add_text_embeds, structure_add_text_embeds, appearance_add_text_embeds = add_text_embeds_list
# 3.3. Prepare added time ids & embeddings
if self.text_encoder_2 is None:
text_encoder_projection_dim = int(pooled_prompt_embeds.shape[-1])
else:
text_encoder_projection_dim = self.text_encoder_2.config.projection_dim
add_time_ids = self._get_add_time_ids(
original_size,
crops_coords_top_left,
target_size,
dtype=self.dtype,
text_encoder_projection_dim=text_encoder_projection_dim,
)
negative_add_time_ids = add_time_ids
add_time_ids = torch.cat([negative_add_time_ids, add_time_ids], dim=0).to(device)
# 4. Prepare timesteps
timesteps, num_inference_steps = retrieve_timesteps(self.scheduler, num_inference_steps, device, timesteps)
# 5. Prepare latent variables
num_channels_latents = self.unet.config.in_channels
# The second variable is _.
latents, _ = self.prepare_latents(
None, batch_size, num_images_per_prompt, num_channels_latents, height, width,
self.dtype, device, generator, latents
)
latents_ = [structure_latents, appearance_latents]
clean_latents_ = []
for image_index, image_ in enumerate([structure_image, appearance_image]):
if image_ is not None:
# The first variable is _.
_, clean_latent = self.prepare_latents(
image_, batch_size, num_images_per_prompt, num_channels_latents, height, width,
self.dtype, device, generator, latents_[image_index]
)
clean_latents_.append(clean_latent)
else:
clean_latents_.append(None)
if latents_[image_index] is None:
latents_[image_index] = latents
latents_ = [latents] + latents_
# clean_structure_latents, clean_appearance_latents = clean_latents_
# 6. Prepare extra step kwargs
extra_step_kwargs = self.prepare_extra_step_kwargs(generator, eta)
# 7. Denoising loop
num_warmup_steps = max(len(timesteps) - num_inference_steps * self.scheduler.order, 0)
# 7.1 Apply denoising_end
if hasattr(self, 'denoising_end') and self.denoising_end is not None and 0.0 < float(self.denoising_end) < 1.0:
discrete_timestep_cutoff = int(
round(
self.scheduler.config.num_train_timesteps
- (self.denoising_end * self.scheduler.config.num_train_timesteps)
)
)
num_inference_steps = len(list(filter(lambda ts: ts >= discrete_timestep_cutoff, timesteps)))
timesteps = timesteps[:num_inference_steps]
# 7.2 Optionally get guidance scale embedding
timestep_cond = None
assert self.unet.config.time_cond_proj_dim is None
# 7.3 Get batch order
batch_order = deepcopy(BATCH_ORDER)
if structure_image is not None: # If image is provided, not generating, so no CFG needed
batch_order.remove("structure_uncond")
if appearance_image is not None:
batch_order.remove("appearance_uncond")
baked_latents = self.cfg_loop(batch_order,
prompt_embeds_list,
add_text_embeds_list,
add_time_ids,
latents_,
clean_latents_,
num_inference_steps,
num_warmup_steps,
extra_step_kwargs,
timesteps,
timestep_cond=timestep_cond,
control_schedule=control_schedule,
self_recurrence_schedule=self_recurrence_schedule,
guidance_rescale=guidance_rescale,
callback=callback,
callback_steps=callback_steps,
cross_attention_kwargs=cross_attention_kwargs)
latents, structure_latents, appearance_latents = baked_latents
# For passing important information onto the refiner
self.refiner_args = {"latents": latents.detach(), "prompt": prompt, "negative_prompt": negative_prompt}
if not output_type == "latent":
# Make sure the VAE is in float32 mode, as it overflows in float16
if self.vae.config.force_upcast:
self.upcast_vae()
vae_dtype = next(iter(self.vae.post_quant_conv.parameters())).dtype
latents = latents.to(vae_dtype)
structure_latents = structure_latents.to(vae_dtype)
appearance_latents = appearance_latents.to(vae_dtype)
image = self.vae.decode(latents / self.vae.config.scaling_factor, return_dict=False)[0]
image = self.image_processor.postprocess(image, output_type=output_type)
if decode_structure:
structure = self.vae.decode(structure_latents / self.vae.config.scaling_factor, return_dict=False)[0]
structure = self.image_processor.postprocess(structure, output_type=output_type)
else:
structure = structure_latents
if decode_appearance:
appearance = self.vae.decode(appearance_latents / self.vae.config.scaling_factor, return_dict=False)[0]
appearance = self.image_processor.postprocess(appearance, output_type=output_type)
else:
appearance = appearance_latents
# Cast back to fp16 if needed
if self.vae.config.force_upcast:
self.vae.to(dtype=torch.float16)
else:
return CtrlXStableDiffusionXLPipelineOutput(
images=latents, structures=structure_latents, appearances=appearance_latents
)
# Offload all models
self.maybe_free_model_hooks()
if not return_dict:
return image, structure, appearance
return CtrlXStableDiffusionXLPipelineOutput(images=image, structures=structure, appearances=appearance)
def cfg_loop(self,
batch_order,
prompt_embeds_list,
add_text_embeds_list,
add_time_ids,
latents_,
clean_latents_,
num_inference_steps,
num_warmup_steps,
extra_step_kwargs,
timesteps,
timestep_cond=None,
control_schedule=None,
self_recurrence_schedule=None,
guidance_rescale=0.0,
callback=None,
callback_steps=None,
callback_on_step_end=None,
callback_on_step_end_tensor_inputs=None,
cross_attention_kwargs=None):
prompt_embeds, structure_prompt_embeds, appearance_prompt_embeds = prompt_embeds_list
add_text_embeds, structure_add_text_embeds, appearance_add_text_embeds = add_text_embeds_list
latents, structure_latents, appearance_latents = latents_
clean_structure_latents, clean_appearance_latents = clean_latents_
structure_control_stop_i, appearance_control_stop_i = get_last_control_i(control_schedule, num_inference_steps)
if self_recurrence_schedule is None:
self_recurrence_schedule = [0] * num_inference_steps
self._num_timesteps = len(timesteps)
with self.progress_bar(total=num_inference_steps) as progress_bar:
for i, t in enumerate(timesteps):
if hasattr(self, 'interrupt') and self.interrupt:
continue
if i == structure_control_stop_i: # If not generating structure/appearance, drop after last control
if "structure_uncond" not in batch_order:
batch_order.remove("structure_cond")
if i == appearance_control_stop_i:
if "appearance_uncond" not in batch_order:
batch_order.remove("appearance_cond")
register_attr(self, t=t.item(), do_control=True, batch_order=batch_order)
# With CFG.
latent_model_input = self.scheduler.scale_model_input(latents, t)
structure_latent_model_input = self.scheduler.scale_model_input(structure_latents, t)
appearance_latent_model_input = self.scheduler.scale_model_input(appearance_latents, t)
pass
all_latent_model_input = {
"structure_uncond": structure_latent_model_input[0:1],
"appearance_uncond": appearance_latent_model_input[0:1],
"uncond": latent_model_input[0:1],
"structure_cond": structure_latent_model_input[0:1],
"appearance_cond": appearance_latent_model_input[0:1],
"cond": latent_model_input[0:1],
}
all_prompt_embeds = {
"structure_uncond": structure_prompt_embeds[0:1],
"appearance_uncond": appearance_prompt_embeds[0:1],
"uncond": prompt_embeds[0:1],
"structure_cond": structure_prompt_embeds[1:2],
"appearance_cond": appearance_prompt_embeds[1:2],
"cond": prompt_embeds[1:2],
}
all_add_text_embeds = {
"structure_uncond": structure_add_text_embeds[0:1],
"appearance_uncond": appearance_add_text_embeds[0:1],
"uncond": add_text_embeds[0:1],
"structure_cond": structure_add_text_embeds[1:2],
"appearance_cond": appearance_add_text_embeds[1:2],
"cond": add_text_embeds[1:2],
}
all_time_ids = {
"structure_uncond": add_time_ids[0:1],
"appearance_uncond": add_time_ids[0:1],
"uncond": add_time_ids[0:1],
"structure_cond": add_time_ids[1:2],
"appearance_cond": add_time_ids[1:2],
"cond": add_time_ids[1:2],
}
concat_latent_model_input = batch_dict_to_tensor(all_latent_model_input, batch_order)
concat_prompt_embeds = batch_dict_to_tensor(all_prompt_embeds, batch_order)
concat_add_text_embeds = batch_dict_to_tensor(all_add_text_embeds, batch_order)
concat_add_time_ids = batch_dict_to_tensor(all_time_ids, batch_order)
# Predict the noise residual
added_cond_kwargs = {"text_embeds": concat_add_text_embeds, "time_ids": concat_add_time_ids}
concat_noise_pred = self.unet(
concat_latent_model_input,
t,
encoder_hidden_states=concat_prompt_embeds,
timestep_cond=timestep_cond,
cross_attention_kwargs=cross_attention_kwargs,
added_cond_kwargs=added_cond_kwargs,
).sample
all_noise_pred = batch_tensor_to_dict(concat_noise_pred, batch_order)
# Classifier-free guidance
noise_pred = all_noise_pred["uncond"] +\
self.guidance_scale * (all_noise_pred["cond"] - all_noise_pred["uncond"])
structure_noise_pred = all_noise_pred["structure_cond"]\
if "structure_cond" in batch_order else noise_pred
if "structure_uncond" in all_noise_pred:
structure_noise_pred = all_noise_pred["structure_uncond"] +\
self.structure_guidance_scale * (structure_noise_pred - all_noise_pred["structure_uncond"])
appearance_noise_pred = all_noise_pred["appearance_cond"]\
if "appearance_cond" in batch_order else noise_pred
if "appearance_uncond" in all_noise_pred:
appearance_noise_pred = all_noise_pred["appearance_uncond"] +\
self.appearance_guidance_scale * (appearance_noise_pred - all_noise_pred["appearance_uncond"])
if guidance_rescale > 0.0:
noise_pred = rescale_noise_cfg(
noise_pred, all_noise_pred["cond"], guidance_rescale=guidance_rescale
)
if "structure_uncond" in all_noise_pred:
structure_noise_pred = rescale_noise_cfg(
structure_noise_pred, all_noise_pred["structure_cond"],
guidance_rescale=guidance_rescale
)
if "appearance_uncond" in all_noise_pred:
appearance_noise_pred = rescale_noise_cfg(
appearance_noise_pred, all_noise_pred["appearance_cond"],
guidance_rescale=guidance_rescale
)
# Compute the previous noisy sample x_t -> x_t-1
concat_noise_pred = torch.cat(
[structure_noise_pred, appearance_noise_pred, noise_pred], dim=0,
)
concat_latents = torch.cat(
[structure_latents, appearance_latents, latents], dim=0,
)
structure_latents, appearance_latents, latents = self.scheduler.step(
concat_noise_pred, t, concat_latents, **extra_step_kwargs,
).prev_sample.chunk(3)
if clean_structure_latents is not None:
structure_latents = noise_prev(self.scheduler, t, clean_structure_latents)
if clean_appearance_latents is not None:
appearance_latents = noise_prev(self.scheduler, t, clean_appearance_latents)
# Self-recurrence
for _ in range(self_recurrence_schedule[i]):
if hasattr(self.scheduler, "_step_index"): # For fancier schedulers
self.scheduler._step_index -= 1 # TODO: Does this actually work?
t_prev = 0 if i + 1 >= num_inference_steps else timesteps[i + 1]
latents = noise_t2t(self.scheduler, t_prev, t, latents)
latent_model_input = torch.cat([latents] * 2)
register_attr(self, t=t.item(), do_control=False, batch_order=["uncond", "cond"])
# Predict the noise residual
added_cond_kwargs = {"text_embeds": add_text_embeds, "time_ids": add_time_ids}
noise_pred_uncond, noise_pred_ = self.unet(
latent_model_input,
t,
encoder_hidden_states=prompt_embeds,
timestep_cond=timestep_cond,
cross_attention_kwargs=cross_attention_kwargs,
added_cond_kwargs=added_cond_kwargs,
).sample.chunk(2)
noise_pred = noise_pred_uncond + self.guidance_scale * (noise_pred_ - noise_pred_uncond)
if guidance_rescale > 0.0:
noise_pred = rescale_noise_cfg(noise_pred, noise_pred_, guidance_rescale=guidance_rescale)
latents = self.scheduler.step(noise_pred, t, latents, **extra_step_kwargs).prev_sample
# Callbacks
assert callback_on_step_end is None
if i == len(timesteps) - 1 or ((i + 1) > num_warmup_steps and (i + 1) % self.scheduler.order == 0):
progress_bar.update()
if callback is not None and i % callback_steps == 0:
step_idx = i // getattr(self.scheduler, "order", 1)
callback(step_idx, t, latents)
# "Reconstruction"
if clean_structure_latents is not None:
structure_latents = clean_structure_latents
if clean_appearance_latents is not None:
appearance_latents = clean_appearance_latents
return latents, structure_latents, appearance_latents
@property
def appearance_guidance_scale(self):
return self._guidance_scale if self._appearance_guidance_scale is None else self._appearance_guidance_scale
@property
def structure_guidance_scale(self):
return self._guidance_scale if self._structure_guidance_scale is None else self._structure_guidance_scale
def prepare_latents(self, image, batch_size, num_images_per_prompt, num_channels_latents, height, width,
dtype, device, generator=None, noise=None):
batch_size = batch_size * num_images_per_prompt
if noise is None:
shape = (
batch_size,
num_channels_latents,
height // self.vae_scale_factor,
width // self.vae_scale_factor
)
noise = randn_tensor(shape, generator=generator, device=device, dtype=dtype)
noise = noise * self.scheduler.init_noise_sigma # Starting noise, need to scale
else:
noise = noise.to(device)
if image is None:
return noise, None
if not isinstance(image, (torch.Tensor, Image.Image, list)):
raise ValueError(
f"`image` has to be of type `torch.Tensor`, `PIL.Image.Image` or list but is {type(image)}"
)
# Offload text encoder if `enable_model_cpu_offload` was enabled
if hasattr(self, "final_offload_hook") and self.final_offload_hook is not None:
self.text_encoder_2.to("cpu")
torch.cuda.empty_cache()
image = image.to(device=device, dtype=dtype)
if image.shape[1] == 4: # Image already in latents form
init_latents = image
else:
# Make sure the VAE is in float32 mode, as it overflows in float16
if self.vae.config.force_upcast:
image = image.to(torch.float32)
self.vae.to(torch.float32)
if isinstance(generator, list) and len(generator) != batch_size:
raise ValueError(
f"You have passed a list of generators of length {len(generator)}, but requested an effective batch"
f" size of {batch_size}. Make sure the batch size matches the length of the generators."
)
elif isinstance(generator, list):
init_latents = [
retrieve_latents(self.vae.encode(image[i : i + 1]), generator=generator[i])
for i in range(batch_size)
]
init_latents = torch.cat(init_latents, dim=0)
else:
init_latents = retrieve_latents(self.vae.encode(image), generator=generator)
if self.vae.config.force_upcast:
self.vae.to(dtype)
init_latents = init_latents.to(dtype)
init_latents = self.vae.config.scaling_factor * init_latents
if batch_size > init_latents.shape[0] and batch_size % init_latents.shape[0] == 0:
# Expand init_latents for batch_size
additional_image_per_prompt = batch_size // init_latents.shape[0]
init_latents = torch.cat([init_latents] * additional_image_per_prompt, dim=0)
elif batch_size > init_latents.shape[0] and batch_size % init_latents.shape[0] != 0:
raise ValueError(
f"Cannot duplicate `image` of batch size {init_latents.shape[0]} to {batch_size} text prompts."
)
else:
init_latents = torch.cat([init_latents], dim=0)
return noise, init_latents
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