Document plan for the rest of the MultiDiffusion implementation.

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Ryan Dick 2024-06-14 18:08:11 -04:00 committed by Kent Keirsey
parent 605f460c7d
commit fc187c9253

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@ -1,12 +1,18 @@
from __future__ import annotations
import math
from contextlib import nullcontext
from typing import Any, Callable, List, Optional
import torch
from invokeai.backend.stable_diffusion.diffusers_pipeline import StableDiffusionGeneratorPipeline
from invokeai.backend.stable_diffusion.diffusers_pipeline import (
AddsMaskGuidance,
ControlNetData,
PipelineIntermediateState,
StableDiffusionGeneratorPipeline,
T2IAdapterData,
is_inpainting_model,
)
from invokeai.backend.stable_diffusion.diffusion.conditioning_data import IPAdapterData, TextConditioningData
from invokeai.backend.stable_diffusion.diffusion.unet_attention_patcher import UNetAttentionPatcher, UNetIPAdapterData
@ -14,6 +20,32 @@ from invokeai.backend.stable_diffusion.diffusion.unet_attention_patcher import U
class MultiDiffusionPipeline(StableDiffusionGeneratorPipeline):
"""A Stable Diffusion pipeline that uses Multi-Diffusion (https://arxiv.org/pdf/2302.08113) for denoising."""
# Plan:
# - latents_from_embeddings(...) will accept all of the same global params, but the "local" params will be bundled
# together with tile locations.
# - What is "local"?:
# - conditioning_data could be local, but for upscaling will be global
# - control_data makes more sense as global, then we split it up as we split up the latents
# - ip_adapter_data sort of has 3 modes to consider:
# - global style: applied in the same way to all tiles
# - local style: apply different IP-Adapters to each tile
# - global structure: we want to crop the input image and run the IP-Adapter on each separately
# - t2i_adapter_data won't be supported at first - it's not popular enough
# - All the inpainting params are global and need to be cropped accordingly
# - Local:
# - latents
# - conditioning_data
# - noise
# - control_data
# - ip_adapter_data (skip for now)
# - t2i_adapter_data (skip for now)
# - mask
# - masked_latents
# - is_gradient_mask ???
# - Can we support inpainting models in this node?
# - TBD, need to think about this more
# - step(...) remains mostly unmodified, is not overriden in this sub-class.
# - May need a cleaner AddsMaskGuidance implementation to handle this plan... we'll see.
def latents_from_embeddings(
self,
latents: torch.Tensor,
@ -142,141 +174,3 @@ class MultiDiffusionPipeline(StableDiffusionGeneratorPipeline):
)
return latents
@torch.inference_mode()
def step(
self,
t: torch.Tensor,
latents: torch.Tensor,
conditioning_data: TextConditioningData,
step_index: int,
total_step_count: int,
scheduler_step_kwargs: dict[str, Any],
mask_guidance: AddsMaskGuidance | None,
mask: torch.Tensor | None,
masked_latents: torch.Tensor | None,
control_data: list[ControlNetData] | None = None,
ip_adapter_data: Optional[list[IPAdapterData]] = None,
t2i_adapter_data: Optional[list[T2IAdapterData]] = None,
):
# invokeai_diffuser has batched timesteps, but diffusers schedulers expect a single value
timestep = t[0]
# Handle masked image-to-image (a.k.a inpainting).
if mask_guidance is not None:
# NOTE: This is intentionally done *before* self.scheduler.scale_model_input(...).
latents = mask_guidance(latents, timestep)
# TODO: should this scaling happen here or inside self._unet_forward?
# i.e. before or after passing it to InvokeAIDiffuserComponent
latent_model_input = self.scheduler.scale_model_input(latents, timestep)
# Handle ControlNet(s)
down_block_additional_residuals = None
mid_block_additional_residual = None
if control_data is not None:
down_block_additional_residuals, mid_block_additional_residual = self.invokeai_diffuser.do_controlnet_step(
control_data=control_data,
sample=latent_model_input,
timestep=timestep,
step_index=step_index,
total_step_count=total_step_count,
conditioning_data=conditioning_data,
)
# Handle T2I-Adapter(s)
down_intrablock_additional_residuals = None
if t2i_adapter_data is not None:
accum_adapter_state = None
for single_t2i_adapter_data in t2i_adapter_data:
# Determine the T2I-Adapter weights for the current denoising step.
first_t2i_adapter_step = math.floor(single_t2i_adapter_data.begin_step_percent * total_step_count)
last_t2i_adapter_step = math.ceil(single_t2i_adapter_data.end_step_percent * total_step_count)
t2i_adapter_weight = (
single_t2i_adapter_data.weight[step_index]
if isinstance(single_t2i_adapter_data.weight, list)
else single_t2i_adapter_data.weight
)
if step_index < first_t2i_adapter_step or step_index > last_t2i_adapter_step:
# If the current step is outside of the T2I-Adapter's begin/end step range, then set its weight to 0
# so it has no effect.
t2i_adapter_weight = 0.0
# Apply the t2i_adapter_weight, and accumulate.
if accum_adapter_state is None:
# Handle the first T2I-Adapter.
accum_adapter_state = [val * t2i_adapter_weight for val in single_t2i_adapter_data.adapter_state]
else:
# Add to the previous adapter states.
for idx, value in enumerate(single_t2i_adapter_data.adapter_state):
accum_adapter_state[idx] += value * t2i_adapter_weight
down_intrablock_additional_residuals = accum_adapter_state
# Handle inpainting models.
if is_inpainting_model(self.unet):
# NOTE: These calls to add_inpainting_channels_to_latents(...) are intentionally done *after*
# self.scheduler.scale_model_input(...) so that the scaling is not applied to the mask or reference image
# latents.
if mask is not None:
if masked_latents is None:
raise ValueError("Source image required for inpaint mask when inpaint model used!")
latent_model_input = self.add_inpainting_channels_to_latents(
latents=latent_model_input, masked_ref_image_latents=masked_latents, inpainting_mask=mask
)
else:
# We are using an inpainting model, but no mask was provided, so we are not really "inpainting".
# We generate a global mask and empty original image so that we can still generate in this
# configuration.
# TODO(ryand): Should we just raise an exception here instead? I can't think of a use case for wanting
# to do this.
# TODO(ryand): If we decide that there is a good reason to keep this, then we should generate the 'fake'
# mask and original image once rather than on every denoising step.
latent_model_input = self.add_inpainting_channels_to_latents(
latents=latent_model_input,
masked_ref_image_latents=torch.zeros_like(latent_model_input[:1]),
inpainting_mask=torch.ones_like(latent_model_input[:1, :1]),
)
uc_noise_pred, c_noise_pred = self.invokeai_diffuser.do_unet_step(
sample=latent_model_input,
timestep=t, # TODO: debug how handled batched and non batched timesteps
step_index=step_index,
total_step_count=total_step_count,
conditioning_data=conditioning_data,
ip_adapter_data=ip_adapter_data,
down_block_additional_residuals=down_block_additional_residuals, # for ControlNet
mid_block_additional_residual=mid_block_additional_residual, # for ControlNet
down_intrablock_additional_residuals=down_intrablock_additional_residuals, # for T2I-Adapter
)
guidance_scale = conditioning_data.guidance_scale
if isinstance(guidance_scale, list):
guidance_scale = guidance_scale[step_index]
noise_pred = self.invokeai_diffuser._combine(uc_noise_pred, c_noise_pred, guidance_scale)
guidance_rescale_multiplier = conditioning_data.guidance_rescale_multiplier
if guidance_rescale_multiplier > 0:
noise_pred = self._rescale_cfg(
noise_pred,
c_noise_pred,
guidance_rescale_multiplier,
)
# compute the previous noisy sample x_t -> x_t-1
step_output = self.scheduler.step(noise_pred, timestep, latents, **scheduler_step_kwargs)
# TODO: discuss injection point options. For now this is a patch to get progress images working with inpainting
# again.
if mask_guidance is not None:
# Apply the mask to any "denoised" or "pred_original_sample" fields.
if hasattr(step_output, "denoised"):
step_output.pred_original_sample = mask_guidance(step_output.denoised, self.scheduler.timesteps[-1])
elif hasattr(step_output, "pred_original_sample"):
step_output.pred_original_sample = mask_guidance(
step_output.pred_original_sample, self.scheduler.timesteps[-1]
)
else:
step_output.pred_original_sample = mask_guidance(latents, self.scheduler.timesteps[-1])
return step_output