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blepping-comfyui_overly_com…/py/substep_samplers.py
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2024-07-07 06:58:55 -06:00

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60 KiB
Python

import contextlib
import math
import torch
import tqdm
import torchsde
import comfy
from comfy.k_diffusion.sampling import (
get_ancestral_step,
to_d,
)
from .res_support import _de_second_order
from .utils import find_first_unsorted, extract_pred, fallback
HAVE_TDE = HAVE_TODE = False
with contextlib.suppress(ImportError):
import torchdiffeq as tde
HAVE_TDE = True
with contextlib.suppress(ImportError, RuntimeError):
import torchode as tode
HAVE_TODE = True
class SamplerResult:
def __init__(
self,
ss,
sampler,
x,
sigma_up=None,
*,
split_result=None,
sigma=None,
sigma_next=None,
sigma_down=None,
s_noise=None,
noise_sampler=None,
final=True,
):
self.sampler = sampler
self.sigma_up = fallback(sigma_up, ss.sigma.new_zeros(1))
self.s_noise = fallback(s_noise, sampler.s_noise)
self.sigma = fallback(sigma, ss.sigma)
self.sigma_next = fallback(sigma_next, ss.sigma_next)
self.sigma_down = fallback(sigma_down, self.sigma_next)
self.noise_sampler = fallback(noise_sampler, sampler.noise_sampler)
self.final = final
self.x_ = x
if split_result is not None:
self.denoised, self.noise_pred = split_result
elif x is None:
raise ValueError("SamplerResult requires at least one of x, split_result")
else:
self.denoised = self.noise_pred = None
_ = self.extract_pred(ss)
self.denoised_uncond = ss.hcur.denoised_uncond
self.denoised_cond = ss.hcur.denoised_cond
def get_noise(self, scaled=True):
if self.sigma_next == 0 or self.noise_scale == 0:
return torch.zeros_like(self.x_)
refs = {
k: getattr(self, ak)
for k, ak in (
("x", "x"),
("noise", "noise_pred"),
("denoised", "denoised"),
("uncond", "denoised_uncond"),
("cond", "denoised_cond"),
("sigma", "sigma"),
("sigma_next", "sigma_next"),
("sigma_down", "sigma_down"),
("sigma_up", "sigma_up"),
)
if getattr(self, ak) is not None
}
return self.noise_sampler(
self.sigma,
self.sigma_next,
out_hw=self.x.shape[-2:],
x_ref=self.x,
refs=refs,
).mul_(self.noise_scale if scaled else 1.0)
def extract_pred(self, ss):
if self.denoised is None or self.noise_pred is None:
self.denoised, self.noise_pred = extract_pred(
ss.hcur.x, self.x_, ss.sigma, self.sigma_down
)
return self.denoised, self.noise_pred
@property
def x(self):
if self.x_ is None:
self.x_ = self.denoised + self.sigma_down * self.noise_pred
return self.x_
@property
def noise_scale(self):
return self.sigma_up * self.s_noise
def noise_x(self, x=None, scale=1.0):
x = fallback(x, self.x)
if self.sigma_next == 0 or self.noise_scale == 0:
return x
x = x + self.get_noise() * scale
return x
def clone(self):
obj = self.__new__(self.__class__)
for k in (
"sampler",
"sigma_up",
"s_noise",
"sigma",
"sigma_next",
"sigma_down",
"noise_sampler",
"final",
"denoised",
"noise_pred",
"x_",
):
setattr(obj, k, getattr(self, k))
return obj
class CFGPPStepMixin:
allow_cfgpp = False
allow_alt_cfgpp = False
def __init__(self):
self.cfgpp = self.allow_cfgpp and self.options.pop("cfgpp", False)
alt_cfgpp_scale = self.options.pop("alt_cfgpp_scale", 0.0)
self.alt_cfgpp_scale = 0.0 if not self.allow_alt_cfgpp else alt_cfgpp_scale
def to_d(self, mr, **kwargs):
return mr.to_d(alt_cfgpp_scale=self.alt_cfgpp_scale, cfgpp=self.cfgpp, **kwargs)
class SingleStepSampler(CFGPPStepMixin):
name = None
self_noise = 0
model_calls = 0
ancestralize = False
sample_sigma_zero = False
def __init__(
self,
*,
noise_sampler=None,
substeps=1,
s_noise=1.0,
eta=1.0,
dyn_eta_start=None,
dyn_eta_end=None,
weight=1.0,
**kwargs,
):
self.options = kwargs
super().__init__()
self.s_noise = s_noise
self.eta = eta
self.dyn_eta_start = dyn_eta_start
self.dyn_eta_end = dyn_eta_end
self.noise_sampler = noise_sampler
self.weight = weight
self.substeps = substeps
def __call__(self, x, ss):
if not self.sample_sigma_zero and ss.sigma_next == 0:
return (yield from self.denoised_result(ss))
next_x = None
sg = self.step(x, ss)
with contextlib.suppress(StopIteration):
while True:
sr = sg.send(next_x)
if sr.final:
if self.ancestralize:
sr = self.ancestralize_result(ss, sr)
return (yield sr)
next_x = sr.x
yield sr
def step(self, x, ss):
raise NotImplementedError
# Euler - based on original ComfyUI implementation
def euler_step(self, x, ss):
sigma_down, sigma_up = ss.get_ancestral_step(self.get_dyn_eta(ss))
d = self.to_d(ss.hcur)
return (yield from self.result(ss, ss.denoised + d * sigma_down, sigma_up))
def denoised_result(self, ss, **kwargs):
return (
yield SamplerResult(ss, self, ss.denoised, ss.sigma.new_zeros(1), **kwargs)
)
def result(self, ss, x, noise_scale=None, **kwargs):
return (yield SamplerResult(ss, self, x, noise_scale, **kwargs))
def split_result(
self, ss, denoised, noise_pred, sigma_up=None, sigma_down=None, **kwargs
):
return (
yield SamplerResult(
ss,
self,
None,
sigma_up,
sigma_down=sigma_down,
split_result=(denoised, noise_pred),
**kwargs,
)
)
def ancestralize_result(self, ss, sr):
new_sr = sr.clone()
if new_sr.sigma_down is not None and new_sr.sigma_down != new_sr.sigma_next:
return sr
eta = self.get_dyn_eta(ss)
if sr.sigma_next == 0 or eta == 0:
return sr
sd, su = ss.get_ancestral_step(eta, sigma=sr.sigma, sigma_next=sr.sigma_next)
_ = new_sr.extract_pred(ss)
new_sr.x_ = None
new_sr.sigma_up = su
new_sr.sigma_down = sd
return new_sr
def __str__(self):
return f"<SS({self.name}): s_noise={self.s_noise}, eta={self.eta}>"
def get_dyn_value(self, ss, start, end):
if None in (start, end):
return 1.0
if start == end:
return start
main_idx = getattr(ss, "main_idx", ss.idx)
main_sigmas = getattr(ss, "main_sigmas", ss.sigmas)
step_pct = main_idx / (len(main_sigmas) - 1)
dd_diff = end - start
return start + dd_diff * step_pct
def get_dyn_eta(self, ss):
return self.eta * self.get_dyn_value(ss, self.dyn_eta_start, self.dyn_eta_end)
def max_noise_samples(self):
return (1 + self.self_noise) * self.substeps
class HistorySingleStepSampler(SingleStepSampler):
default_history_limit, max_history = 0, 0
def __init__(self, *args, history_limit=None, **kwargs):
super().__init__(*args, **kwargs)
self.history_limit = min(
self.max_history,
max(
0,
self.default_history_limit if history_limit is None else history_limit,
),
)
def available_history(self, ss):
return max(
0, min(ss.idx, self.history_limit, self.max_history, len(ss.hist) - 1)
)
class ReversibleSingleStepSampler(HistorySingleStepSampler):
def __init__(
self,
*,
reversible_scale=1.0,
reta=1.0,
dyn_reta_start=None,
dyn_reta_end=None,
reversible_start_step=0,
**kwargs,
):
super().__init__(**kwargs)
self.reversible_scale = reversible_scale
self.reta = reta
self.reversible_start_step = reversible_start_step
self.dyn_reta_start = dyn_reta_start
self.dyn_reta_end = dyn_reta_end
def reversible_correction(self, ss):
raise NotImplementedError
def get_dyn_reta(self, ss):
if ss.step < self.reversible_start_step:
return 0.0
return self.reta * self.get_dyn_value(
ss, self.dyn_reta_start, self.dyn_reta_end
)
def get_reversible_cfg(self, ss):
if ss.step < self.reversible_start_step:
return 0.0, 0.0
return self.get_dyn_reta(ss), self.reversible_scale
class DPMPPStepMixin:
@staticmethod
def sigma_fn(t):
return t.neg().exp()
@staticmethod
def t_fn(t):
return t.log().neg()
class MinSigmaStepMixin:
@staticmethod
def adjust_step(sigma, min_sigma, threshold=5e-04):
if min_sigma - sigma > threshold:
return sigma.clamp(min=min_sigma)
return sigma
def adjusted_step(self, ss, sn, result, mcc, sigma_up):
if sn == ss.sigma_next:
return sigma_up, result
# FIXME: Make sure we're noising from the right sigma.
result = yield from self.result(
ss, result, sigma_up, sigma=ss.sigma, sigma_next=sn, final=False
)
mr = ss.model(result, sn, model_call_idx=mcc)
dt = ss.sigma_next - sn
result = result + self.to_d(mr) * dt
return sigma_up.new_zeros(1), result
class EulerStep(SingleStepSampler):
name = "euler"
allow_cfgpp = True
step = SingleStepSampler.euler_step
class CycleSingleStepSampler(SingleStepSampler):
def __init__(self, *, cycle_pct=0.25, **kwargs):
super().__init__(**kwargs)
self.cycle_pct = cycle_pct
def get_cycle_scales(self, sigma_next):
keep_scale = sigma_next * (1.0 - self.cycle_pct)
add_scale = ((sigma_next**2.0 - keep_scale**2.0) ** 0.5) * (
0.95 + 0.25 * self.cycle_pct
)
# print(f">> keep={keep_scale}, add={add_scale}")
return keep_scale, add_scale
class EulerCycleStep(CycleSingleStepSampler):
name = "euler_cycle"
allow_alt_cfgpp = True
allow_cfgpp = True
def step(self, x, ss):
if ss.sigma_next == 0:
return (yield from self.denoised_result(ss))
d = self.to_d(ss.hcur)
keep_scale, add_scale = self.get_cycle_scales(ss.sigma_next)
yield from self.result(ss, ss.denoised + d * keep_scale, add_scale)
class DPMPP2MStep(HistorySingleStepSampler, DPMPPStepMixin):
name = "dpmpp_2m"
default_history_limit, max_history = 1, 1
ancestralize = True
def step(self, x, ss):
s, sn = ss.sigma, ss.sigma_next
t, t_next = self.t_fn(s), self.t_fn(sn)
h = t_next - t
st, st_next = self.sigma_fn(t), self.sigma_fn(t_next)
if self.available_history(ss) > 0:
h_last = t - self.t_fn(ss.sigma_prev)
r = h_last / h
denoised, old_denoised = ss.denoised, ss.hprev.denoised
denoised_d = (1 + 1 / (2 * r)) * denoised - (1 / (2 * r)) * old_denoised
else:
denoised_d = ss.denoised
yield from self.result(ss, (st_next / st) * x - (-h).expm1() * denoised_d)
class DPMPP2MSDEStep(HistorySingleStepSampler):
name = "dpmpp_2m_sde"
default_history_limit, max_history = 1, 1
def __init__(self, *, solver_type="midpoint", **kwargs):
super().__init__(**kwargs)
self.solver_type = solver_type
def step(self, x, ss):
denoised = ss.denoised
# DPM-Solver++(2M) SDE
t, s = -ss.sigma.log(), -ss.sigma_next.log()
h = s - t
eta_h = self.get_dyn_eta(ss) * h
x = (
ss.sigma_next / ss.sigma * (-eta_h).exp() * x
+ (-h - eta_h).expm1().neg() * denoised
)
noise_strength = ss.sigma_next * (-2 * eta_h).expm1().neg().sqrt()
if self.available_history(ss) == 0:
return (yield from self.result(ss, x, noise_strength))
h_last = (-ss.sigma.log()) - (-ss.sigma_prev.log())
r = h_last / h
old_denoised = ss.hprev.denoised
if self.solver_type == "heun":
x = x + (
((-h - eta_h).expm1().neg() / (-h - eta_h) + 1)
* (1 / r)
* (denoised - old_denoised)
)
elif self.solver_type == "midpoint":
x = x + 0.5 * (-h - eta_h).expm1().neg() * (1 / r) * (
denoised - old_denoised
)
yield from self.result(ss, x, noise_strength)
class DPMPP3MSDEStep(HistorySingleStepSampler):
name = "dpmpp_3m_sde"
default_history_limit, max_history = 2, 2
def step(self, x, ss):
denoised = ss.denoised
t, s = -ss.sigma.log(), -ss.sigma_next.log()
h = s - t
eta = self.get_dyn_eta(ss)
h_eta = h * (eta + 1)
x = torch.exp(-h_eta) * x + (-h_eta).expm1().neg() * denoised
noise_strength = ss.sigma_next * (-2 * h * eta).expm1().neg().sqrt()
ah = self.available_history(ss)
if ah == 0:
return (yield from self.result(ss, x, noise_strength))
hist = ss.hist
h_1 = (-ss.sigma.log()) - (-ss.sigma_prev.log())
denoised_1 = hist[-2].denoised
if ah == 1:
r = h_1 / h
d = (denoised - denoised_1) / r
phi_2 = h_eta.neg().expm1() / h_eta + 1
x = x + phi_2 * d
else: # 2+ history items available
h_2 = (-ss.sigma_prev.log()) - (-ss.sigmas[ss.idx - 2].log())
denoised_2 = hist[-3].denoised
r0 = h_1 / h
r1 = h_2 / h
d1_0 = (denoised - denoised_1) / r0
d1_1 = (denoised_1 - denoised_2) / r1
d1 = d1_0 + (d1_0 - d1_1) * r0 / (r0 + r1)
d2 = (d1_0 - d1_1) / (r0 + r1)
phi_2 = h_eta.neg().expm1() / h_eta + 1
phi_3 = phi_2 / h_eta - 0.5
x = x + phi_2 * d1 - phi_3 * d2
yield from self.result(ss, x, noise_strength)
# Based on original implementation from https://github.com/Clybius/ComfyUI-Extra-Samplers
class ReversibleHeunStep(ReversibleSingleStepSampler):
name = "reversible_heun"
model_calls = 1
allow_alt_cfgpp = True
allow_cfgpp = True
def step(self, x, ss):
sigma_down, sigma_up = ss.get_ancestral_step(self.get_dyn_eta(ss))
reta, reversible_scale = self.get_reversible_cfg(ss)
sigma_down_reversible, _sigma_up_reversible = ss.get_ancestral_step(reta)
dt_reversible = sigma_down_reversible - ss.sigma
# Calculate the derivative using the model
d = self.to_d(ss.hcur)
# Predict the sample at the next sigma using Euler step
x_pred = ss.denoised + d * sigma_down
# Denoised sample at the next sigma
mr_next = ss.model(x_pred, sigma_down, model_call_idx=1)
# Calculate the derivative at the next sigma
d_next = self.to_d(mr_next)
# Update the sample using the Reversible Heun formula
correction = dt_reversible**2 * (d_next - d) / 4
x = (
mr_next.denoised
+ (sigma_down * (d + d_next) / 2)
- correction * reversible_scale
)
yield from self.result(ss, x, sigma_up)
# Based on original implementation from https://github.com/Clybius/ComfyUI-Extra-Samplers
class ReversibleHeun1SStep(ReversibleSingleStepSampler):
name = "reversible_heun_1s"
model_calls = 1
default_history_limit, max_history = 1, 1
allow_alt_cfgpp = True
allow_cfgpp = True
def step(self, x, ss):
if self.available_history(ss) < 1:
return (yield from ReversibleHeunStep.step(self, x, ss))
s = ss.sigma
# Reversible Heun-inspired update (first-order)
sd, su = ss.get_ancestral_step(self.get_dyn_eta(ss))
reta, reversible_scale = self.get_reversible_cfg(ss)
sdr, _sur = ss.get_ancestral_step(reta)
dt, dtr = sd - s, sdr - s
# eff_x = ss.hist[-1].x if ah > 0 else x
eff_x = x
# Calculate the derivative using the model
# d_prev = self.to_d(
# ss.hist[-2] if ah > 0 else ss.hist[-1],
# x=eff_x,
# sigma=s,
# )
prev_mr = ss.hist[-2]
# d_prev = self.to_d(prev_mr, x=eff_x, sigma=s)
d_prev = self.to_d(prev_mr, sigma=ss.sigma_prev)
# Predict the sample at the next sigma using Euler step
# x_pred = ss.denoised + d_prev * sd
x_pred = eff_x + d_prev * dt
# x_pred = ss.denoised + d_prev * sd
# Calculate the derivative at the next sigma
d_next = self.to_d(ss.hcur, x=x_pred, sigma=sd)
# Update the sample using the Reversible Heun formula
correction = dtr**2 * (d_next - d_prev) / 4
x = x + (dt * (d_prev + d_next) / 2) - correction * reversible_scale
yield from self.result(ss, x, su)
def __step(self, x, ss):
if ss.sigma_next == 0:
return self.euler_step(x, ss)
# Reversible Heun-inspired update (first-order)
sigma_down, sigma_up = ss.get_ancestral_step(self.get_dyn_eta(ss))
sigma_down_reversible, sigma_up_reversible = ss.get_ancestral_step(
self.get_dyn_reta(ss)
)
sigma_i, sigma_i_plus_1 = ss.sigma, sigma_down
dt = sigma_i_plus_1 - sigma_i
dt_reversible = sigma_down_reversible - sigma_i
eff_x = ss.hist[-2 if len(ss.hist) > 1 else -1].x
# eff_x = ss.hist[-2].x if len(ss.hist) > 1 else x
# Calculate the derivative using the model
eff_mr = ss.hprev if len(ss.hist) > 1 else ss.hcur
d_i_old = self.to_d(eff_mr)
# d_i_old = self.to_d(ss.hprev if len(ss.hist) > 1 else ss.hcur)
# d_i_old = to_d(
# eff_x,
# sigma_i if len(ss.hist) == 1 else ss.sigma_prev,
# ss.hist[-2].denoised
# if len(ss.hist) > 1
# else ss.model(eff_x, sigma_i, model_call_idx=1).denoised,
# )
# Predict the sample at the next sigma using Euler step
x_pred = eff_x + d_i_old * dt
# Calculate the derivative at the next sigma
d_i_plus_1 = to_d(x_pred, sigma_i_plus_1, ss.denoised)
# Update the sample using the Reversible Heun formula
x = (
x
+ dt * (d_i_old + d_i_plus_1) / 2
- dt_reversible**2 * (d_i_plus_1 - d_i_old) / 4
)
yield from self.result(ss, x, sigma_up)
# return x, sigma_up
def _step(self, x, ss):
if ss.sigma_next == 0:
return (yield from self.euler_step(x, ss))
ah = self.available_history(ss)
s = ss.sigma
# Reversible Heun-inspired update (first-order)
sd, su = ss.get_ancestral_step(self.get_dyn_eta(ss))
sdr, _sur = ss.get_ancestral_step(self.get_dyn_reta(ss))
dt, dtr = sd - s, sdr - s
# eff_mr = ss.hprev if ah > 0 else ss.hcur
# eff_x = ss.hist[-1].x if ah > 0 else x # This probably doesn't make sense.
# Calculate the derivative using the model
# mr_prev = ss.hist[-2] if ah > 0 else ss.model(eff_x, s, model_call_idx=1)
mr_prev = ss.hist[-2 if ah > 0 else -1]
d_prev = self.to_d(mr_prev, x=x, sigma=ss.sigma)
# d_prev = self.to_d(
# mr_prev, sigma=ss.sigma_prev if ss.sigma_prev is not None else ss.sigma
# )
# Predict the sample at the next sigma using Euler step
x_pred = ss.denoised + d_prev * sd
# x_pred = mr_prev.denoised + d_prev * sd
# x_pred = eff_x + d_prev * dt
# Calculate the derivative at the next sigma
d_next = self.to_d(ss.hcur, x=x_pred, sigma=sd)
# Update the sample using the Reversible Heun formula
correction = dtr**2 * (d_next - d_prev) / 4
# x = x + (dt * (d_prev + d_next) / 2) - correction * self.reversible_scale
x = (
ss.denoised
+ (sd * (d_prev + d_next) / 2)
- correction * self.reversible_scale
)
yield from self.result(ss, x, su)
# Based on original implementation from https://github.com/Clybius/ComfyUI-Extra-Samplers
class RESStep(SingleStepSampler):
name = "res"
model_calls = 1
def __init__(self, *, res_simple_phi=False, res_c2=0.5, **kwargs):
super().__init__(**kwargs)
self.simple_phi = res_simple_phi
self.c2 = res_c2
def step(self, x, ss):
eta = self.get_dyn_eta(ss)
sigma_down, sigma_up = ss.get_ancestral_step(eta)
denoised = ss.denoised
lam_next = sigma_down.log().neg() if eta != 0 else ss.sigma_next.log().neg()
lam = ss.sigma.log().neg()
h = lam_next - lam
a2_1, b1, b2 = _de_second_order(
h=h, c2=self.c2, simple_phi_calc=self.simple_phi
)
c2_h = 0.5 * h
x_2 = math.exp(-c2_h) * x + a2_1 * h * denoised
lam_2 = lam + c2_h
sigma_2 = lam_2.neg().exp()
denoised2 = ss.model(x_2, sigma_2, model_call_idx=1).denoised
x = math.exp(-h) * x + h * (b1 * denoised + b2 * denoised2)
yield from self.result(ss, x, sigma_up)
# Based on original implementation from https://github.com/Clybius/ComfyUI-Extra-Samplers
class TrapezoidalStep(SingleStepSampler):
name = "trapezoidal"
model_calls = 1
allow_alt_cfgpp = True
def step(self, x, ss):
sigma_down, sigma_up = ss.get_ancestral_step(self.get_dyn_eta(ss))
# Calculate the derivative using the model
d_i = self.to_d(ss.hcur)
# Predict the sample at the next sigma using Euler step
x_pred = x + d_i * ss.dt
# Denoised sample at the next sigma
mr_next = ss.model(x_pred, ss.sigma_next, model_call_idx=1)
# Calculate the derivative at the next sigma
d_next = self.to_d(mr_next)
dt_2 = sigma_down - ss.sigma
# Update the sample using the Trapezoidal rule
x = x + dt_2 * (d_i + d_next) / 2
yield from self.result(ss, x, sigma_up)
class TrapezoidalCycleStep(CycleSingleStepSampler):
name = "trapezoidal_cycle"
model_calls = 1
allow_alt_cfgpp = True
def step(self, x, ss):
# Calculate the derivative using the model
d_i = self.to_d(ss.hcur)
# Predict the sample at the next sigma using Euler step
x_pred = x + d_i * ss.dt
# Denoised sample at the next sigma
mr_next = ss.model(x_pred, ss.sigma_next, model_call_idx=1)
# Calculate the derivative at the next sigma
d_next = self.to_d(mr_next)
# Update the sample using the Trapezoidal rule
keep_scale, add_scale = self.get_cycle_scales(ss.sigma_next)
noise_pred = (d_i + d_next) * 0.5 # Combined noise prediction
denoised_pred = x - noise_pred * ss.sigma # Denoised prediction
yield from self.result(ss, denoised_pred + noise_pred * keep_scale, add_scale)
# Based on original implementation from https://github.com/Clybius/ComfyUI-Extra-Samplers
class BogackiStep(ReversibleSingleStepSampler):
name = "bogacki"
reversible = False
model_calls = 2
allow_alt_cfgpp = True
def __init__(self, *args, **kwargs):
super().__init__(*args, **kwargs)
if not self.reversible:
self.reversible_scale = 0
def step(self, x, ss):
s = ss.sigma
sd, su = ss.get_ancestral_step(self.get_dyn_eta(ss))
reta, reversible_scale = self.get_reversible_cfg(ss)
sdr, _sur = ss.get_ancestral_step(reta)
dt, dtr = sd - s, sdr - s
# Calculate the derivative using the model
d = self.to_d(ss.hcur)
# Bogacki-Shampine steps
k1 = d * dt
k2 = self.to_d(ss.model(x + k1 / 2, s + dt / 2, model_call_idx=1)) * dt
k3 = (
self.to_d(
ss.model(x + 3 * k1 / 4 + k2 / 4, s + 3 * dt / 4, model_call_idx=2)
)
* dt
)
# Reversible correction term (inspired by Reversible Heun)
correction = dtr**2 * (k3 - k2) / 6
# Update the sample
x = (x + 2 * k1 / 9 + k2 / 3 + 4 * k3 / 9) - correction * reversible_scale
yield from self.result(ss, x, su)
class ReversibleBogackiStep(BogackiStep):
name = "reversible_bogacki"
reversible = True
# Based on original implementation from https://github.com/Clybius/ComfyUI-Extra-Samplers
class RK4Step(SingleStepSampler):
name = "rk4"
model_calls = 3
allow_alt_cfgpp = True
def step(self, x, ss):
sigma_down, sigma_up = ss.get_ancestral_step(self.get_dyn_eta(ss))
sigma = ss.sigma
# Calculate the derivative using the model
d = to_d(x, sigma, ss.denoised)
dt = sigma_down - sigma
# Runge-Kutta steps
k1 = d * dt
k2 = self.to_d(ss.model(x + k1 / 2, sigma + dt / 2, model_call_idx=1)) * dt
k3 = self.to_d(ss.model(x + k2 / 2, sigma + dt / 2, model_call_idx=2)) * dt
k4 = self.to_d(ss.model(x + k3, sigma + dt, model_call_idx=3)) * dt
# Update the sample
x = x + (k1 + 2 * k2 + 2 * k3 + k4) / 6
yield from self.result(ss, x, sigma_up)
# Based on original implementation from https://github.com/Clybius/ComfyUI-Extra-Samplers
class EulerDancingStep(SingleStepSampler):
name = "euler_dancing"
self_noise = 1
def __init__(
self,
*,
deta=1.0,
ds_noise=None,
leap=2,
dyn_deta_start=None,
dyn_deta_end=None,
dyn_deta_mode="lerp",
**kwargs,
):
super().__init__(**kwargs)
self.deta = deta
self.ds_noise = ds_noise if ds_noise is not None else self.s_noise
self.leap = leap
self.dyn_deta_start = dyn_deta_start
self.dyn_deta_end = dyn_deta_end
if dyn_deta_mode not in ("lerp", "lerp_alt", "deta"):
raise ValueError("Bad dyn_deta_mode")
self.dyn_deta_mode = dyn_deta_mode
def step(self, x, ss):
eta = self.eta
deta = self.deta
leap_sigmas = ss.sigmas[ss.idx :]
leap_sigmas = leap_sigmas[: find_first_unsorted(leap_sigmas)]
zero_idx = (leap_sigmas <= 0).nonzero().flatten()[:1]
max_leap = (zero_idx.item() if len(zero_idx) else len(leap_sigmas)) - 1
is_danceable = max_leap > 1 and ss.sigma_next != 0
curr_leap = max(1, min(self.leap, max_leap))
sigma_leap = leap_sigmas[curr_leap] if is_danceable else ss.sigma_next
del leap_sigmas
sigma_down, sigma_up = get_ancestral_step(ss.sigma, sigma_leap, eta)
print("???", sigma_down, sigma_up)
d = to_d(x, ss.sigma, ss.denoised)
# Euler method
dt = sigma_down - ss.sigma
x = x + d * dt
if curr_leap == 1:
return (yield from self.result(ss, x, sigma_up))
noise_strength = self.ds_noise * sigma_up
if noise_strength != 0:
x = yield from self.result(
ss, x, sigma_up, sigma_next=sigma_leap, final=False
)
# x = x + self.noise_sampler(ss.sigma, sigma_leap).mul_(
# self.ds_noise * sigma_up
# )
# sigma_down2, sigma_up2 = get_ancestral_step(sigma_leap, ss.sigma, eta=deta)
# _sigma_down2, sigma_up2 = get_ancestral_step(sigma_leap, ss.sigma, eta=deta)
# sigma_up2 = ss.sigma_next + (ss.sigma - ss.sigma_next) * 0.5
sigma_up2 = get_ancestral_step(ss.sigma_next, sigma_leap, eta=deta)[1] + (
ss.sigma_next * 0.5
)
sigma_down2, _sigma_up2 = get_ancestral_step(
ss.sigma_next, sigma_leap, eta=deta
)
print(">>>", sigma_down2, sigma_up2, "--", ss.sigma, "->", sigma_leap)
# sigma_down2, sigma_up2 = get_ancestral_step(ss.sigma_next, sigma_leap, eta=deta)
d_2 = to_d(x, sigma_leap, ss.denoised)
dt_2 = sigma_down2 - sigma_leap
x = x + d_2 * dt_2
yield from self.result(ss, x, sigma_up2)
def _step(self, x, ss):
eta = self.get_dyn_eta(ss)
leap_sigmas = ss.sigmas[ss.idx :]
leap_sigmas = leap_sigmas[: find_first_unsorted(leap_sigmas)]
zero_idx = (leap_sigmas <= 0).nonzero().flatten()[:1]
max_leap = (zero_idx.item() if len(zero_idx) else len(leap_sigmas)) - 1
is_danceable = max_leap > 1 and ss.sigma_next != 0
curr_leap = max(1, min(self.leap, max_leap))
sigma_leap = leap_sigmas[curr_leap] if is_danceable else ss.sigma_next
# DANCE 35 6 tensor(10.0947, device='cuda:0') -- tensor([21.9220,
# print("DANCE", max_leap, curr_leap, sigma_leap, "--", leap_sigmas)
del leap_sigmas
sigma_down, sigma_up = get_ancestral_step(ss.sigma, sigma_leap, eta)
d = to_d(x, ss.sigma, ss.denoised)
# Euler method
dt = sigma_down - ss.sigma
x = x + d * dt
if curr_leap == 1:
return x, sigma_up
dance_scale = self.get_dyn_value(ss, self.dyn_deta_start, self.dyn_deta_end)
if curr_leap == 1 or not is_danceable or abs(dance_scale) < 1e-04:
print("NODANCE", dance_scale, self.deta, is_danceable, ss.sigma_next)
yield SamplerResult(ss, self, x, sigma_up)
print(
"DANCE", dance_scale, self.deta, self.dyn_deta_mode, self.ds_noise, sigma_up
)
sigma_down_normal, sigma_up_normal = get_ancestral_step(
ss.sigma, ss.sigma_next, eta
)
if self.dyn_deta_mode == "lerp":
dt_normal = sigma_down_normal - ss.sigma
x_normal = x + d * dt_normal
else:
x_normal = x
sigma_down2, sigma_up2 = get_ancestral_step(
sigma_leap,
ss.sigma_next,
eta=self.deta * (1.0 if self.dyn_deta_mode != "deta" else dance_scale),
)
print(
"-->",
sigma_down2,
sigma_up2,
"--",
self.deta * (1.0 if self.dyn_deta_mode != "deta" else dance_scale),
)
x = x + self.noise_sampler(ss.sigma, sigma_leap).mul_(self.ds_noise * sigma_up)
d_2 = to_d(x, sigma_leap, ss.denoised)
dt_2 = sigma_down2 - sigma_leap
result = x + d_2 * dt_2
# SIGMA: norm_up=9.062416076660156, up=10.703859329223633, up2=19.376544952392578, str=21.955078125
noise_strength = sigma_up2 + ((sigma_up - sigma_up_normal) ** 5.0)
noise_strength = sigma_up2 + ((sigma_up2 - sigma_up) * 0.5)
# noise_strength = sigma_up2 + (
# (sigma_up2 - sigma_up) ** (1.0 - (sigma_up_normal / sigma_up2))
# )
noise_diff = (
sigma_up - sigma_up_normal
if sigma_up > sigma_up_normal
else sigma_up_normal - sigma_up
)
noise_div = (
sigma_up / sigma_up_normal
if sigma_up > sigma_up_normal
else sigma_up_normal / sigma_up
)
noise_diff = sigma_up2 - sigma_up_normal
noise_div = sigma_up2 / sigma_up_normal
noise_div = ss.sigma / sigma_leap
# noise_strength = sigma_up2 + (noise_diff * noise_div)
# noise_strength = sigma_up2 + ((noise_diff * 0.5) ** 2.0)
# noise_strength = sigma_up2 + ((1.0 - noise_diff) ** 0.5)
# noise_strength = sigma_up2 + (((sigma_up2 - sigma_up) * 0.5) ** 2.0)
# noise_strength = sigma_up2 + (((sigma_up2 - sigma_up_normal) * 0.5) ** 1.5)
# noise_strength = sigma_up2 + (
# (noise_diff * 0.1875) ** (1.0 / (noise_div - 0.0))
# )
# noise_strength = sigma_up2 + (
# (noise_diff * 0.125) ** (1.0 / (noise_div * 1.25))
# )
# noise_strength = sigma_up2 + ((noise_diff * 0.2) ** (1.0 / (noise_div * 1.0)))
noise_strength = sigma_up2 + (noise_diff * 0.9 * max(0.0, noise_div - 0.8))
noise_strength = sigma_up2 + (
(noise_diff / (curr_leap * 0.4))
* ((noise_div - (curr_leap / 2.0)).clamp(min=0, max=1.5) * 1.0)
)
# (1.0 / (noise_div * 1.25)))
# noise_strength = sigma_up2 + ((noise_diff * 0.5) ** noise_div)
print(
f"SIGMA: norm_up={sigma_up_normal}, up={sigma_up}, up2={sigma_up2}, str={noise_strength}",
# noise_diff,
noise_div,
)
return result, noise_strength
noise_diff = sigma_up2 - sigma_up * dance_scale
noise_scale = sigma_up2 + noise_diff * (0.025 * curr_leap)
# noise_scale = sigma_up2 * self.ds_noise
if self.dyn_deta_mode == "deta" or dance_scale == 1.0:
return result, noise_scale
result = torch.lerp(x_normal, result, dance_scale)
# FIXME: Broken for noise samplers that care about s/sn
return result, noise_scale
# def step(self, x, ss):
# eta = self.get_dyn_eta(ss)
# leap_sigmas = ss.sigmas[ss.idx :]
# leap_sigmas = leap_sigmas[: find_first_unsorted(leap_sigmas)]
# zero_idx = (leap_sigmas <= 0).nonzero().flatten()[:1]
# max_leap = (zero_idx.item() if len(zero_idx) else len(leap_sigmas)) - 1
# is_danceable = max_leap > 1 and ss.sigma_next != 0
# curr_leap = max(1, min(self.leap, max_leap))
# sigma_leap = leap_sigmas[curr_leap] if is_danceable else ss.sigma_next
# # print("DANCE", max_leap, curr_leap, sigma_leap, "--", leap_sigmas)
# del leap_sigmas
# sigma_down, sigma_up = get_ancestral_step(ss.sigma, sigma_leap, eta)
# d = to_d(x, ss.sigma, ss.denoised)
# # Euler method
# dt = sigma_down - ss.sigma
# x = x + d * dt
# if curr_leap == 1:
# return x, sigma_up
# dance_scale = self.get_dyn_value(ss, self.dyn_deta_start, self.dyn_deta_end)
# if not is_danceable or abs(dance_scale) < 1e-04:
# print("NODANCE", dance_scale, self.deta)
# return x, sigma_up
# print("NODANCE", dance_scale, self.deta)
# sigma_down_normal, _sigma_up_normal = get_ancestral_step(
# ss.sigma, ss.sigma_next, eta
# )
# if self.dyn_deta_mode == "lerp":
# dt_normal = sigma_down_normal - ss.sigma
# x_normal = x + d * dt_normal
# else:
# x_normal = x
# x = x + self.noise_sampler(ss.sigma, sigma_leap).mul_(self.s_noise * sigma_up)
# sigma_down2, sigma_up2 = get_ancestral_step(
# sigma_leap,
# ss.sigma_next,
# eta=self.deta * (1.0 if self.dyn_deta_mode != "deta" else dance_scale),
# )
# d_2 = to_d(x, sigma_leap, ss.denoised)
# dt_2 = sigma_down2 - sigma_leap
# result = x + d_2 * dt_2
# noise_diff = sigma_up2 - sigma_up * dance_scale
# noise_scale = sigma_up2 + noise_diff * (0.025 * curr_leap)
# if self.dyn_deta_mode == "deta" or dance_scale == 1.0:
# return result, noise_scale
# result = torch.lerp(x_normal, result, dance_scale)
# # FIXME: Broken for noise samplers that care about s/sn
# return result, noise_scale
class DPMPP2SStep(SingleStepSampler, DPMPPStepMixin):
name = "dpmpp_2s"
model_calls = 1
def step(self, x, ss):
t_fn, sigma_fn = self.t_fn, self.sigma_fn
sigma_down, sigma_up = ss.get_ancestral_step(self.get_dyn_eta(ss))
# DPM-Solver++(2S)
t, t_next = t_fn(ss.sigma), t_fn(sigma_down)
r = 1 / 2
h = t_next - t
s = t + r * h
x_2 = (sigma_fn(s) / sigma_fn(t)) * x - (-h * r).expm1() * ss.denoised
denoised_2 = ss.model(x_2, sigma_fn(s), model_call_idx=1).denoised
x = (sigma_fn(t_next) / sigma_fn(t)) * x - (-h).expm1() * denoised_2
yield from self.result(ss, x, sigma_up)
class DPMPPSDEStep(SingleStepSampler, DPMPPStepMixin):
name = "dpmpp_sde"
self_noise = 1
model_calls = 1
def __init__(self, *args, r=1 / 2, **kwargs):
super().__init__(*args, **kwargs)
self.r = r
def step(self, x, ss):
t_fn, sigma_fn = self.t_fn, self.sigma_fn
r, eta = self.r, self.get_dyn_eta(ss)
# DPM-Solver++
t, t_next = t_fn(ss.sigma), t_fn(ss.sigma_next)
h = t_next - t
s = t + h * r
fac = 1 / (2 * r)
# Step 1
sd, su = get_ancestral_step(sigma_fn(t), sigma_fn(s), eta)
s_ = t_fn(sd)
x_2 = (sigma_fn(s_) / sigma_fn(t)) * x - (t - s_).expm1() * ss.denoised
x_2 = yield from self.result(
ss, x_2, su, sigma=sigma_fn(t), sigma_next=sigma_fn(s), final=False
)
denoised_2 = ss.model(x_2, sigma_fn(s), model_call_idx=1).denoised
# Step 2
sd, su = get_ancestral_step(sigma_fn(t), sigma_fn(t_next), eta)
t_next_ = t_fn(sd)
denoised_d = (1 - fac) * ss.denoised + fac * denoised_2
x = (sigma_fn(t_next_) / sigma_fn(t)) * x - (t - t_next_).expm1() * denoised_d
yield from self.result(ss, x, su)
# Based on implementation from https://github.com/Clybius/ComfyUI-Extra-Samplers
# Which was originally written by Katherine Crowson
class TTMJVPStep(SingleStepSampler):
name = "ttm_jvp"
model_calls = 1
def __init__(self, *args, alternate_phi_2_calc=True, **kwargs):
super().__init__(*args, **kwargs)
self.alternate_phi_2_calc = alternate_phi_2_calc
def step(self, x, ss):
eta = self.get_dyn_eta(ss)
sigma, sigma_next = ss.sigma, ss.sigma_next
# 2nd order truncated Taylor method
t, s = -sigma.log(), -sigma_next.log()
h = s - t
h_eta = h * (eta + 1)
eps = to_d(x, sigma, ss.denoised)
denoised_prime = ss.model(
x, sigma, tangents=(eps * -sigma, -sigma), model_call_idx=1
).jdenoised
phi_1 = -torch.expm1(-h_eta)
if self.alternate_phi_2_calc:
phi_2 = torch.expm1(-h) + h # seems to work better with eta > 0
else:
phi_2 = torch.expm1(-h_eta) + h_eta
x = torch.exp(-h_eta) * x + phi_1 * ss.denoised + phi_2 * denoised_prime
noise_scale = (
sigma_next * torch.sqrt(-torch.expm1(-2 * h * eta))
if eta
else ss.sigma.new_zeros(1)
)
yield from self.result(ss, x, noise_scale)
# Adapted from https://github.com/zju-pi/diff-sampler/blob/main/diff-solvers-main/solvers.py
# under Apache 2 license
class IPNDMStep(HistorySingleStepSampler):
name = "ipndm"
ancestralize = True
default_history_limit, max_history = 1, 3
allow_alt_cfgpp = True
IPNDM_MULTIPLIERS = (
((1,), 1),
((3, -1), 2),
((23, -16, 5), 12),
((55, -59, 37, -9), 24),
)
def step(self, x, ss):
order = self.available_history(ss) + 1
if order > 1:
hd = tuple(self.to_d(ss.hist[-hidx]) for hidx in range(order, 1, -1))
(dm, *hms), divisor = self.IPNDM_MULTIPLIERS[order - 1]
noise = dm * self.to_d(ss.hcur)
for hidx, hm in enumerate(hms, start=1):
noise += hm * hd[-hidx]
noise /= divisor
yield from self.result(ss, x + ss.dt * noise)
# Adapted from https://github.com/zju-pi/diff-sampler/blob/main/diff-solvers-main/solvers.py
# under Apache 2 license
class IPNDMVStep(HistorySingleStepSampler):
name = "ipndm_v"
ancestralize = True
default_history_limit, max_history = 1, 3
allow_alt_cfgpp = True
def step(self, x, ss):
dt = ss.dt
d = self.to_d(ss.hcur)
order = self.available_history(ss) + 1
if order > 1:
hd = tuple(self.to_d(ss.hist[-hidx]) for hidx in range(order, 1, -1))
hns = (
ss.sigmas[ss.idx - (order - 2) : ss.idx + 1]
- ss.sigmas[ss.idx - (order - 1) : ss.idx]
)
if order == 1:
noise = d
elif order == 2:
coeff1 = (2 + (dt / hns[-1])) / 2
coeff2 = -(dt / hns[-1]) / 2
noise = coeff1 * d + coeff2 * hd[-1]
elif order == 3:
temp = (
1
- dt
/ (3 * (dt + hns[-1]))
* (dt * (dt + hns[-1]))
/ (hns[-1] * (hns[-1] + hns[-2]))
) / 2
coeff1 = (2 + (dt / hns[-1])) / 2 + temp
coeff2 = -(dt / hns[-1]) / 2 - (1 + hns[-1] / hns[-2]) * temp
coeff3 = temp * hns[-1] / hns[-2]
noise = coeff1 * d + coeff2 * hd[-1] + coeff3 * hd[-2]
else:
temp1 = (
1
- dt
/ (3 * (dt + hns[-1]))
* (dt * (dt + hns[-1]))
/ (hns[-1] * (hns[-1] + hns[-2]))
) / 2
temp2 = (
(
(1 - dt / (3 * (dt + hns[-1]))) / 2
+ (1 - dt / (2 * (dt + hns[-1])))
* dt
/ (6 * (dt + hns[-1] + hns[-2]))
)
* (dt * (dt + hns[-1]) * (dt + hns[-1] + hns[-2]))
/ (hns[-1] * (hns[-1] + hns[-2]) * (hns[-1] + hns[-2] + hns[-3]))
)
coeff1 = (2 + (dt / hns[-1])) / 2 + temp1 + temp2
coeff2 = (
-(dt / hns[-1]) / 2
- (1 + hns[-1] / hns[-2]) * temp1
- (
1
+ (hns[-1] / hns[-2])
+ (hns[-1] * (hns[-1] + hns[-2]) / (hns[-2] * (hns[-2] + hns[-3])))
)
* temp2
)
coeff3 = (
temp1 * hns[-1] / hns[-2]
+ (
(hns[-1] / hns[-2])
+ (hns[-1] * (hns[-1] + hns[-2]) / (hns[-2] * (hns[-2] + hns[-3])))
* (1 + hns[-2] / hns[-3])
)
* temp2
)
coeff4 = (
-temp2
* (hns[-1] * (hns[-1] + hns[-2]) / (hns[-2] * (hns[-2] + hns[-3])))
* hns[-1]
/ hns[-2]
)
noise = coeff1 * d + coeff2 * hd[-1] + coeff3 * hd[-2] + coeff4 * hd[-3]
yield from self.result(ss, x + ss.dt * noise)
class DEISStep(HistorySingleStepSampler):
name = "deis"
ancestralize = True
default_history_limit, max_history = 1, 3
allow_alt_cfgpp = True
def __init__(self, *args, deis_mode="tab", **kwargs):
super().__init__(*args, **kwargs)
self.deis_mode = deis_mode
self.deis_coeffs_key = None
self.deis_coeffs = None
def get_deis_coeffs(self, ss):
key = (
self.history_limit,
len(ss.sigmas),
ss.sigmas[0].item(),
ss.sigmas[-1].item(),
)
if self.deis_coeffs_key == key:
return self.deis_coeffs
self.deis_coeffs_key = key
self.deis_coeffs = comfy.k_diffusion.deis.get_deis_coeff_list(
ss.sigmas, self.history_limit + 1, deis_mode=self.deis_mode
)
return self.deis_coeffs
def step(self, x, ss):
dt = ss.dt
d = self.to_d(ss.hcur)
order = self.available_history(ss) + 1
if order < 2:
noise = dt * d # Euler
else:
c = self.get_deis_coeffs(ss)[ss.idx]
hd = tuple(self.to_d(ss.hist[-hidx]) for hidx in range(order, 1, -1))
noise = c[0] * d
for i in range(1, order):
noise += c[i] * hd[-i]
yield from self.result(ss, x + noise)
class HeunPP2Step(SingleStepSampler):
name = "heunpp2"
ancestralize = True
model_calls = 2
allow_alt_cfgpp = True
def __init__(self, *args, max_order=3, **kwargs):
super().__init__(*args, **kwargs)
self.max_order = max(1, min(self.model_calls + 1, max_order))
def step(self, x, ss):
steps_remain = max(0, len(ss.sigmas) - (ss.idx + 2))
order = min(self.max_order, steps_remain + 1)
sn = ss.sigma_next
if order == 1:
return (yield from self.euler_step(x, ss))
d = self.to_d(ss.hcur)
dt = ss.dt
w = order * ss.sigma
w2 = sn / w
x_2 = x + d * dt
d_2 = self.to_d(ss.model(x_2, sn, model_call_idx=1))
if order == 2:
# Heun's method (ish)
w1 = 1 - w2
d_prime = d * w1 + d_2 * w2
else:
# Heun++ (ish)
snn = ss.sigmas[ss.idx + 2]
dt_2 = snn - sn
x_3 = x_2 + d_2 * dt_2
d_3 = self.to_d(ss.model(x_3, snn, model_call_idx=2))
w3 = snn / w
w1 = 1 - w2 - w3
d_prime = w1 * d + w2 * d_2 + w3 * d_3
yield from self.result(ss, x + d_prime * dt)
class DESolverStep(SingleStepSampler, MinSigmaStepMixin):
de_default_solver = None
sample_sigma_zero = True
def __init__(
self,
*args,
de_solver=None,
de_max_nfe=100,
de_rtol=-2.5,
de_atol=-3.5,
de_fixup_hack=0.025,
de_split=1,
de_min_sigma=0.0292,
**kwargs,
):
self.check_solver_support()
if not HAVE_TDE:
raise RuntimeError(
"TDE sampler requires torchdiffeq installed in venv. Example: pip install torchdiffeq"
)
super().__init__(*args, **kwargs)
de_solver = self.de_default_solver if de_solver is None else de_solver
self.de_solver_name = de_solver
self.de_max_nfe = de_max_nfe
self.de_rtol = 10**de_rtol
self.de_atol = 10**de_atol
self.de_fixup_hack = de_fixup_hack
self.de_split = de_split
self.de_min_sigma = de_min_sigma if de_min_sigma is not None else 0.0
def check_solver_support(self):
raise NotImplementedError
def de_get_step(self, ss, x):
eta = self.get_dyn_eta(ss)
s, sn = ss.sigma, ss.sigma_next
sn = self.adjust_step(sn, self.de_min_sigma)
sigma_down, sigma_up = ss.get_ancestral_step(eta, sigma_next=sn)
if self.de_fixup_hack != 0:
sigma_down = (sigma_down - (s - sigma_down) * self.de_fixup_hack).clamp(
min=0
)
return s, sn, sigma_down, sigma_up
class TDEStep(DESolverStep):
name = "tde"
model_calls = 2
allow_alt_cfgpp = True
allow_cfgpp = False
de_default_solver = "rk4"
def __init__(
self,
*args,
de_split=1,
**kwargs,
):
super().__init__(*args, **kwargs)
self.de_split = de_split
def check_solver_support(self):
if not HAVE_TDE:
raise RuntimeError(
"TODE sampler requires torchdiffeq installed in venv. Example: pip install torchdiffeq"
)
def step(self, x, ss):
s, sn, sigma_down, sigma_up = self.de_get_step(ss, x)
delta = (s - sigma_down).item()
mcc = 0
bidx = 0
pbar = None
def odefn(t, y):
nonlocal mcc
if t < 1e-05:
return torch.zeros_like(y)
if mcc >= self.de_max_nfe:
raise RuntimeError("TDEStep: Model call limit exceeded")
pct = (s - t) / delta
pbar.n = round(min(999, pct.item() * 999))
pbar.update(0)
pbar.set_description(
f"{self.de_solver_name}({mcc}/{self.de_max_nfe})", refresh=True
)
if t == ss.sigma and torch.equal(x[bidx], y):
mr = ss.hcur
mcc = 1
else:
mr = ss.model(y.unsqueeze(0), t, model_call_idx=mcc, s_in=t.new_ones(1))
mcc += 1
return self.to_d(mr)[0]
result = torch.zeros_like(x)
t = sigma_down.new_zeros(self.de_split + 1)
torch.linspace(ss.sigma, sigma_down, t.shape[0], out=t)
for batch in tqdm.trange(
1,
x.shape[0] + 1,
desc="batch",
leave=True,
disable=x.shape[0] == 1 or ss.disable_status,
):
bidx = batch - 1
mcc = 0
if pbar is not None:
pbar.close()
pbar = tqdm.tqdm(
total=1000,
desc=self.de_solver_name,
leave=True,
disable=ss.disable_status,
)
solution = tde.odeint(
odefn,
x[bidx],
t,
rtol=self.de_rtol,
atol=self.de_atol,
method=self.de_solver_name,
options={
"min_step": 1e-05,
"dtype": torch.float64,
},
)[-1]
result[bidx] = solution
sigma_up, result = yield from self.adjusted_step(ss, sn, result, mcc, sigma_up)
if pbar is not None:
pbar.n = pbar.total
pbar.update(0)
pbar.close()
yield from self.result(ss, result, sigma_up, sigma_down=sigma_down)
class TODEStep(DESolverStep):
name = "tode"
model_calls = 2
allow_alt_cfgpp = True
de_default_solver = "dopri5"
def __init__(
self,
*args,
de_initial_step=0.25,
de_compile=False,
de_ctl_pcoeff=0.3,
de_ctl_icoeff=0.9,
de_ctl_dcoeff=0.2,
**kwargs,
):
if not HAVE_TODE:
raise RuntimeError(
"TODE sampler requires torchode installed in venv. Example: pip install torchode"
)
super().__init__(*args, **kwargs)
self.de_solver_method = tode.interface.METHODS[self.de_solver_name]
self.de_ctl_pcoeff = de_ctl_pcoeff
self.de_ctl_icoeff = de_ctl_icoeff
self.de_ctl_dcoeff = de_ctl_dcoeff
self.de_compile = de_compile
self.de_initial_step = de_initial_step
def check_solver_support(self):
if not HAVE_TODE:
raise RuntimeError(
"TODE sampler requires torchode installed in venv. Example: pip install torchode"
)
def step(self, x, ss):
s, sn, sigma_down, sigma_up = self.de_get_step(ss, x)
delta = (ss.sigma - sigma_down).item()
mcc = 0
pbar = None
b, c, h, w = x.shape
def odefn(t, y_flat):
nonlocal mcc
if torch.all(t <= 1e-05).item():
return torch.zeros_like(y_flat)
if mcc >= self.de_max_nfe:
raise RuntimeError("TDEStep: Model call limit exceeded")
pct = (s - t) / delta
pbar.n = round(pct.min().item() * 999)
pbar.update(0)
pbar.set_description(
f"{self.de_solver_name}({mcc}/{self.de_max_nfe})", refresh=True
)
y = y_flat.reshape(-1, c, h, w)
t32 = t.to(torch.float32)
del y_flat
if mcc == 0 and torch.all(t == s):
mr = ss.hcur
mcc = 1
else:
mr = ss.model(y, t32.clamp(min=1e-05), model_call_idx=mcc)
mcc += 1
result = self.to_d(mr).flatten(start_dim=1)
for bi in range(t.shape[0]):
if t[bi] <= 1e-05:
result[bi, :] = 0
return result
t = torch.stack((s, sigma_down)).to(torch.float64).repeat(b, 1)
pbar = tqdm.tqdm(
total=1000, desc=self.de_solver_name, leave=True, disable=ss.disable_status
)
term = tode.DETerm(odefn)
method = self.de_solver_method(term=term)
controller = tode.PIDController(
term=term,
atol=self.de_atol,
rtol=self.de_rtol,
dt_min=1e-05,
pcoeff=self.de_ctl_pcoeff,
icoeff=self.de_ctl_icoeff,
dcoeff=self.de_ctl_dcoeff,
)
solver_ = tode.AutoDiffAdjoint(method, controller)
solver = solver_ if not self.de_compile else torch.compile(solver_)
problem = tode.InitialValueProblem(
y0=x.flatten(start_dim=1), t_start=t[:, 0], t_end=t[:, -1]
)
dt0 = (
(t[:, -1] - t[:, 0]) * self.de_initial_step
if self.de_initial_step
else None
)
solution = solver.solve(problem, dt0=dt0)
# print("\nSOLUTION", solution.stats, solution.ys.shape)
result = solution.ys[:, -1].reshape(-1, c, h, w)
del solution
sigma_up, result = yield from self.adjusted_step(ss, sn, result, mcc, sigma_up)
if pbar is not None:
pbar.n = pbar.total
pbar.update(0)
pbar.close()
yield from self.result(ss, result, sigma_up, sigma_down=sigma_down)
class TSDEStep(DESolverStep):
name = "tsde"
model_calls = 2
allow_alt_cfgpp = True
de_default_solver = "reversible_heun"
def __init__(
self,
*args,
de_initial_step=0.25,
de_split=1,
de_adaptive=False,
de_noise_type="scalar",
de_sde_type="stratonovich",
de_levy_area_approx="none",
de_noise_channels=1,
de_g_multiplier=0.05,
de_g_reverse_time=True,
de_g_derp_mode=False,
**kwargs,
):
super().__init__(*args, **kwargs)
self.de_initial_step = de_initial_step
self.de_adaptive = de_adaptive
self.de_split = de_split
self.de_noise_type = de_noise_type
self.de_sde_type = de_sde_type
self.de_levy_area_approx = de_levy_area_approx
self.de_g_multiplier = de_g_multiplier
self.de_noise_channels = de_noise_channels
self.de_g_reverse_time = de_g_reverse_time
self.de_g_derp_mode = de_g_derp_mode
def check_solver_support(self):
pass
def step(self, x, ss):
s, sn, sigma_down, sigma_up = self.de_get_step(ss, x)
delta = (ss.sigma - sigma_down).item()
mcc = 0
pbar = None
b, c, h, w = x.shape
outer_self = self
class SDE(torch.nn.Module):
noise_type = outer_self.de_noise_type
sde_type = outer_self.de_sde_type
@torch.no_grad()
def f(self, t_rev, y_flat):
nonlocal mcc
t = s - (t_rev - sigma_down)
# print(f"\nf at t_rev={t_rev}, t={t} :: {y_flat.shape}")
if torch.all(t <= 1e-05).item():
return torch.zeros_like(y_flat)
if mcc >= outer_self.de_max_nfe:
raise RuntimeError("TDEStep: Model call limit exceeded")
pct = (s - t) / delta
pbar.n = round(pct.min().item() * 999)
pbar.update(0)
pbar.set_description(
f"{outer_self.de_solver_name}({mcc}/{outer_self.de_max_nfe})",
refresh=True,
)
y = y_flat.reshape(-1, c, h, w)
t32 = t.to(torch.float32)
del y_flat
if mcc == 0 and torch.all(t == s):
mr = ss.hcur
mcc = 1
else:
mr = ss.model(y, t32.clamp(min=1e-05), model_call_idx=mcc)
mcc += 1
return -outer_self.to_d(mr).flatten(start_dim=1)
@torch.no_grad()
def g(self, t_rev, y_flat):
t = (s - sigma_down) - (t_rev - sigma_down)
pct = t / (s - sigma_down)
if outer_self.de_g_reverse_time:
pct = 1.0 - pct
multiplier = outer_self.de_g_multiplier
if outer_self.de_g_derp_mode and mcc % 2 == 0:
multiplier *= -1
val = t * pct * multiplier
if self.noise_type == "diagonal":
out = val.repeat(*y_flat.shape)
elif self.noise_type == "scalar":
out = val.repeat(*y_flat.shape, 1)
else:
out = val.repeat(*y_flat.shape, outer_self.de_noise_channels)
return out
t = torch.stack((sigma_down, s)).to(torch.float)
pbar = tqdm.tqdm(
total=1000, desc=self.de_solver_name, leave=True, disable=ss.disable_status
)
dt0 = (
delta * self.de_initial_step if self.de_adaptive else delta / self.de_split
)
sde = SDE()
y_flat = x.flatten(start_dim=1)
if sde.noise_type == "diagonal":
bm_size = (b, y_flat.shape[1])
elif sde.noise_type == "scalar":
bm_size = (b, 1)
else:
bm_size = (b, self.de_noise_channels)
bm = torchsde.BrownianInterval(
dtype=x.dtype,
device=x.device,
t0=-s,
t1=s,
entropy=ss.noise.seed,
levy_area_approximation=self.de_levy_area_approx,
tol=1e-06,
size=bm_size,
)
ys = torchsde.sdeint(
sde,
y_flat,
t,
method=self.de_solver_name,
adaptive=self.de_adaptive,
atol=self.de_atol,
rtol=self.de_rtol,
dt=dt0,
bm=bm,
)
del y_flat
# print("DONE", ys.shape)
result = ys[-1].reshape(-1, c, h, w)
del ys
sigma_up, result = yield from self.adjusted_step(ss, sn, result, mcc, sigma_up)
if pbar is not None:
pbar.n = pbar.total
pbar.update(0)
pbar.close()
yield from self.result(ss, result, sigma_up, sigma_down=sigma_down)
class HeunStep(ReversibleSingleStepSampler):
name = "heun"
model_calls = 1
default_history_limit, max_history = 0, 0
allow_alt_cfgpp = True
allow_cfgpp = True
def reversible_correction(self, ss, d_from, d_to):
reta, reversible_scale = self.get_reversible_cfg(ss)
if reversible_scale == 0:
return 0
sdr = ss.get_ancestral_step(reta)[0]
dtr = sdr - ss.sigma
return (dtr**2 * (d_to - d_from) / 4) * self.reversible_scale
def step(self, x, ss):
s = ss.sigma
sd, su = ss.get_ancestral_step(self.get_dyn_eta(ss))
dt = sd - s
hcur = ss.hcur
d = self.to_d(hcur)
x_next = hcur.denoised + d * sd
d_next = self.to_d(ss.model(x_next, sd))
result = hcur.denoised + d * s
result += (dt * (d + d_next)) * 0.5
result -= self.reversible_correction(ss, d, d_next)
yield from self.result(ss, result, su)
class Heun1SStep(HeunStep):
name = "heun_1s"
model_calls = 1
allow_alt_cfgpp = True
allow_cfgpp = True
default_history_limit, max_history = 1, 1
def step(self, x, ss):
s = ss.sigma
if self.available_history(ss) == 0:
return (yield from super().step(x, ss))
hcur, hprev = ss.hcur, ss.hprev
d_prev = self.to_d(hprev)
sd, su = ss.get_ancestral_step(self.get_dyn_eta(ss))
dt = sd - s
d = self.to_d(hcur)
result = hcur.denoised + hcur.sigma * self.to_d(hcur)
result += (dt * (d_prev + d)) * 0.5
result -= self.reversible_correction(ss, d_prev, d)
yield from self.result(ss, result, su)
STEP_SAMPLERS = {
"default (euler)": EulerStep,
"bogacki (2)": BogackiStep,
"deis": DEISStep,
"dpmpp_2m_sde": DPMPP2MSDEStep,
"dpmpp_2m": DPMPP2MStep,
"dpmpp_2s": DPMPP2SStep,
"dpmpp_3m_sde": DPMPP3MSDEStep,
"dpmpp_sde (1)": DPMPPSDEStep,
"euler_cycle": EulerCycleStep,
"euler_dancing": EulerDancingStep,
"euler": EulerStep,
"heun (1)": HeunStep,
"heun_1s (1)": Heun1SStep,
"heunpp (1-2)": HeunPP2Step,
"ipndm_v": IPNDMVStep,
"ipndm": IPNDMStep,
"res (1)": RESStep,
"reversible_bogacki (2)": ReversibleBogackiStep,
"reversible_heun (1)": ReversibleHeunStep,
"reversible_heun_1s": ReversibleHeun1SStep,
"rk4 (3)": RK4Step,
"tde (variable)": TDEStep,
"tode (variable)": TODEStep,
"trapezoidal (1)": TrapezoidalStep,
"trapezoidal_cycle (1)": TrapezoidalCycleStep,
"tsde (variable)": TSDEStep,
"ttm_jvp (1)": TTMJVPStep,
}
__all__ = (
"STEP_SAMPLERS",
"EulerStep",
"EulerCycleStep",
"DPMPP2MStep",
"DPMPP2MSDEStep",
"DPMPP3MSDEStep",
"DPMPP2SStep",
"ReversibleHeunStep",
"ReversibleHeun1SStep",
"RESStep",
"TrapezoidalCycleStep",
"TrapezoidalStep",
"BogackiStep",
"ReversibleBogackiStep",
"EulerDancingStep",
"TTMJVPStep",
"IPNDMStep",
"IPNDMVStep",
"TDEStep",
)