InvokeAI/ldm/models/diffusion/shared_invokeai_diffusion.py
Lincoln Stein 0d0481ce75 inpaint model progress
- working with plain prompts, weighted prompts and merge prompts
- not tested with prompt2prompt
2022-10-26 22:40:01 -04:00

189 lines
10 KiB
Python

from math import ceil
from typing import Callable, Optional
import torch
from ldm.models.diffusion.cross_attention_control import CrossAttentionControl
class InvokeAIDiffuserComponent:
'''
The aim of this component is to provide a single place for code that can be applied identically to
all InvokeAI diffusion procedures.
At the moment it includes the following features:
* Cross Attention Control ("prompt2prompt")
'''
class ExtraConditioningInfo:
def __init__(self, cross_attention_control_args: Optional[CrossAttentionControl.Arguments]):
self.cross_attention_control_args = cross_attention_control_args
@property
def wants_cross_attention_control(self):
return self.cross_attention_control_args is not None
def __init__(self, model, model_forward_callback:
Callable[[torch.Tensor, torch.Tensor, torch.Tensor], torch.Tensor]
):
"""
:param model: the unet model to pass through to cross attention control
:param model_forward_callback: a lambda with arguments (x, sigma, conditioning_to_apply). will be called repeatedly. most likely, this should simply call model.forward(x, sigma, conditioning)
"""
self.model = model
self.model_forward_callback = model_forward_callback
def setup_cross_attention_control(self, conditioning: ExtraConditioningInfo, step_count: int):
self.conditioning = conditioning
self.cross_attention_control_context = CrossAttentionControl.Context(
arguments=self.conditioning.cross_attention_control_args,
step_count=step_count
)
CrossAttentionControl.setup_cross_attention_control(self.model,
cross_attention_control_args=self.conditioning.cross_attention_control_args
)
#todo: refactor edited_conditioning, edit_opcodes, edit_options into a struct
#todo: apply edit_options using step_count
def remove_cross_attention_control(self):
self.conditioning = None
self.cross_attention_control_context = None
CrossAttentionControl.remove_cross_attention_control(self.model)
def do_diffusion_step(self, x: torch.Tensor, sigma: torch.Tensor,
unconditioning: torch.Tensor, conditioning: torch.Tensor,
unconditional_guidance_scale: float,
step_index: int=None
):
"""
:param x: Current latents
:param sigma: aka t, passed to the internal model to control how much denoising will occur
:param unconditioning: [B x 77 x 768] embeddings for unconditioned output
:param conditioning: [B x 77 x 768] embeddings for conditioned output
:param unconditional_guidance_scale: aka CFG scale, controls how much effect the conditioning tensor has
:param step_index: Counts upwards from 0 to (step_count-1) (as passed to setup_cross_attention_control, if using). May be called multiple times for a single step, therefore do not assume that its value will monotically increase.
:return: the new latents after applying the model to x using unscaled unconditioning and CFG-scaled conditioning.
"""
CrossAttentionControl.clear_requests(self.model)
cross_attention_control_types_to_do = []
if self.cross_attention_control_context is not None:
if step_index is not None:
# percent_through will never reach 1.0 (but this is intended)
percent_through = float(step_index) / float(self.cross_attention_control_context.step_count)
else:
# find the current sigma in the sigma sequence
# todo: this doesn't work with k_dpm_2 because the sigma used jumps around in the sequence
sigma_index = torch.nonzero(self.model.sigmas <= sigma)[-1]
# flip because sigmas[0] is for the fully denoised image
# percent_through must be <1
percent_through = 1.0 - float(sigma_index.item() + 1) / float(self.model.sigmas.shape[0])
#print('estimated percent_through', percent_through, 'from sigma', sigma.item())
cross_attention_control_types_to_do = CrossAttentionControl.get_active_cross_attention_control_types_for_step(self.cross_attention_control_context, percent_through)
if len(cross_attention_control_types_to_do)==0:
#print('not doing cross attention control')
# faster batched path
x_twice = torch.cat([x]*2)
sigma_twice = torch.cat([sigma]*2)
if isinstance(conditioning, dict):
assert isinstance(unconditioning, dict)
both_conditionings = dict()
for k in conditioning:
if isinstance(conditioning[k], list):
both_conditionings[k] = [
torch.cat([unconditioning[k][i], conditioning[k][i]])
for i in range(len(conditioning[k]))
]
else:
both_conditionings[k] = torch.cat([unconditioning[k], conditioning[k]])
else:
both_conditionings = torch.cat([unconditioning, conditioning])
unconditioned_next_x, conditioned_next_x = self.model_forward_callback(x_twice, sigma_twice, both_conditionings).chunk(2)
else:
#print('pct', percent_through, ': doing cross attention control on', cross_attention_control_types_to_do)
# slower non-batched path (20% slower on mac MPS)
# We are only interested in using attention maps for conditioned_next_x, but batching them with generation of
# unconditioned_next_x causes attention maps to *also* be saved for the unconditioned_next_x.
# This messes app their application later, due to mismatched shape of dim 0 (seems to be 16 for batched vs. 8)
# (For the batched invocation the `wrangler` function gets attention tensor with shape[0]=16,
# representing batched uncond + cond, but then when it comes to applying the saved attention, the
# wrangler gets an attention tensor which only has shape[0]=8, representing just self.edited_conditionings.)
# todo: give CrossAttentionControl's `wrangler` function more info so it can work with a batched call as well.
unconditioned_next_x = self.model_forward_callback(x, sigma, unconditioning)
# process x using the original prompt, saving the attention maps
for type in cross_attention_control_types_to_do:
CrossAttentionControl.request_save_attention_maps(self.model, type)
_ = self.model_forward_callback(x, sigma, conditioning)
CrossAttentionControl.clear_requests(self.model)
# process x again, using the saved attention maps to control where self.edited_conditioning will be applied
for type in cross_attention_control_types_to_do:
CrossAttentionControl.request_apply_saved_attention_maps(self.model, type)
edited_conditioning = self.conditioning.cross_attention_control_args.edited_conditioning
conditioned_next_x = self.model_forward_callback(x, sigma, edited_conditioning)
CrossAttentionControl.clear_requests(self.model)
# to scale how much effect conditioning has, calculate the changes it does and then scale that
scaled_delta = (conditioned_next_x - unconditioned_next_x) * unconditional_guidance_scale
combined_next_x = unconditioned_next_x + scaled_delta
return combined_next_x
# todo: make this work
@classmethod
def apply_conjunction(cls, x, t, forward_func, uc, c_or_weighted_c_list, global_guidance_scale):
x_in = torch.cat([x] * 2)
t_in = torch.cat([t] * 2) # aka sigmas
deltas = None
uncond_latents = None
weighted_cond_list = c_or_weighted_c_list if type(c_or_weighted_c_list) is list else [(c_or_weighted_c_list, 1)]
# below is fugly omg
num_actual_conditionings = len(c_or_weighted_c_list)
conditionings = [uc] + [c for c,weight in weighted_cond_list]
weights = [1] + [weight for c,weight in weighted_cond_list]
chunk_count = ceil(len(conditionings)/2)
deltas = None
for chunk_index in range(chunk_count):
offset = chunk_index*2
chunk_size = min(2, len(conditionings)-offset)
if chunk_size == 1:
c_in = conditionings[offset]
latents_a = forward_func(x_in[:-1], t_in[:-1], c_in)
latents_b = None
else:
c_in = torch.cat(conditionings[offset:offset+2])
latents_a, latents_b = forward_func(x_in, t_in, c_in).chunk(2)
# first chunk is guaranteed to be 2 entries: uncond_latents + first conditioining
if chunk_index == 0:
uncond_latents = latents_a
deltas = latents_b - uncond_latents
else:
deltas = torch.cat((deltas, latents_a - uncond_latents))
if latents_b is not None:
deltas = torch.cat((deltas, latents_b - uncond_latents))
# merge the weighted deltas together into a single merged delta
per_delta_weights = torch.tensor(weights[1:], dtype=deltas.dtype, device=deltas.device)
normalize = False
if normalize:
per_delta_weights /= torch.sum(per_delta_weights)
reshaped_weights = per_delta_weights.reshape(per_delta_weights.shape + (1, 1, 1))
deltas_merged = torch.sum(deltas * reshaped_weights, dim=0, keepdim=True)
# old_return_value = super().forward(x, sigma, uncond, cond, cond_scale)
# assert(0 == len(torch.nonzero(old_return_value - (uncond_latents + deltas_merged * cond_scale))))
return uncond_latents + deltas_merged * global_guidance_scale