bypass implementation

This commit is contained in:
Kohaku-Blueleaf 2026-01-19 11:37:23 +08:00
parent aa77a8a461
commit 2a420dc4db
6 changed files with 1104 additions and 82 deletions

View File

@ -62,9 +62,13 @@ class BOFTAdapter(WeightAdapterBase):
alpha = v[2]
dora_scale = v[3]
blocks = comfy.model_management.cast_to_device(blocks, weight.device, intermediate_dtype)
blocks = comfy.model_management.cast_to_device(
blocks, weight.device, intermediate_dtype
)
if rescale is not None:
rescale = comfy.model_management.cast_to_device(rescale, weight.device, intermediate_dtype)
rescale = comfy.model_management.cast_to_device(
rescale, weight.device, intermediate_dtype
)
boft_m, block_num, boft_b, *_ = blocks.shape
@ -74,7 +78,7 @@ class BOFTAdapter(WeightAdapterBase):
# for Q = -Q^T
q = blocks - blocks.transpose(-1, -2)
normed_q = q
if alpha > 0: # alpha in boft/bboft is for constraint
if alpha > 0: # alpha in boft/bboft is for constraint
q_norm = torch.norm(q) + 1e-8
if q_norm > alpha:
normed_q = q * alpha / q_norm
@ -83,13 +87,13 @@ class BOFTAdapter(WeightAdapterBase):
r = r.to(weight)
inp = org = weight
r_b = boft_b//2
r_b = boft_b // 2
for i in range(boft_m):
bi = r[i]
g = 2
k = 2**i * r_b
if strength != 1:
bi = bi * strength + (1-strength) * I
bi = bi * strength + (1 - strength) * I
inp = (
inp.unflatten(0, (-1, g, k))
.transpose(1, 2)
@ -98,18 +102,117 @@ class BOFTAdapter(WeightAdapterBase):
)
inp = torch.einsum("b i j, b j ...-> b i ...", bi, inp)
inp = (
inp.flatten(0, 1).unflatten(0, (-1, k, g)).transpose(1, 2).flatten(0, 2)
inp.flatten(0, 1)
.unflatten(0, (-1, k, g))
.transpose(1, 2)
.flatten(0, 2)
)
if rescale is not None:
inp = inp * rescale
lora_diff = inp - org
lora_diff = comfy.model_management.cast_to_device(lora_diff, weight.device, intermediate_dtype)
lora_diff = comfy.model_management.cast_to_device(
lora_diff, weight.device, intermediate_dtype
)
if dora_scale is not None:
weight = weight_decompose(dora_scale, weight, lora_diff, alpha, strength, intermediate_dtype, function)
weight = weight_decompose(
dora_scale,
weight,
lora_diff,
alpha,
strength,
intermediate_dtype,
function,
)
else:
weight += function((strength * lora_diff).type(weight.dtype))
except Exception as e:
logging.error("ERROR {} {} {}".format(self.name, key, e))
return weight
def _get_orthogonal_matrices(self, device, dtype):
"""Compute the orthogonal rotation matrices R from BOFT blocks."""
v = self.weights
blocks = v[0].to(device=device, dtype=dtype)
alpha = v[2]
if alpha is None:
alpha = 0
boft_m, block_num, boft_b, _ = blocks.shape
I = torch.eye(boft_b, device=device, dtype=dtype)
# Q = blocks - blocks^T (skew-symmetric)
q = blocks - blocks.transpose(-1, -2)
normed_q = q
# Apply constraint if alpha > 0
if alpha > 0:
q_norm = torch.norm(q) + 1e-8
if q_norm > alpha:
normed_q = q * alpha / q_norm
# Cayley transform: R = (I + Q)(I - Q)^-1
r = (I + normed_q) @ (I - normed_q).float().inverse()
return r, boft_m, boft_b
def g(self, y: torch.Tensor) -> torch.Tensor:
"""
Output transformation for BOFT: applies butterfly orthogonal transform.
BOFT uses multiple stages of butterfly-structured orthogonal transforms.
Reference: LyCORIS ButterflyOFTModule._bypass_forward
"""
v = self.weights
rescale = v[1]
r, boft_m, boft_b = self._get_orthogonal_matrices(y.device, y.dtype)
r_b = boft_b // 2
# Apply multiplier
multiplier = getattr(self, "multiplier", 1.0)
I = torch.eye(boft_b, device=y.device, dtype=y.dtype)
# Use module info from bypass injection to determine conv vs linear
is_conv = getattr(self, "is_conv", y.dim() > 2)
if is_conv:
# Conv output: (N, C, H, W, ...) -> transpose to (N, H, W, ..., C)
y = y.transpose(1, -1)
# Apply butterfly transform stages
inp = y
for i in range(boft_m):
bi = r[i] # (block_num, boft_b, boft_b)
g = 2
k = 2**i * r_b
# Interpolate with identity based on multiplier
if multiplier != 1:
bi = bi * multiplier + (1 - multiplier) * I
# Reshape for butterfly: unflatten last dim, transpose, flatten, unflatten
inp = (
inp.unflatten(-1, (-1, g, k))
.transpose(-2, -1)
.flatten(-3)
.unflatten(-1, (-1, boft_b))
)
# Apply block-diagonal orthogonal transform
inp = torch.einsum("b i j, ... b j -> ... b i", bi, inp)
# Reshape back
inp = (
inp.flatten(-2).unflatten(-1, (-1, k, g)).transpose(-2, -1).flatten(-3)
)
# Apply rescale if present
if rescale is not None:
rescale = rescale.to(device=y.device, dtype=y.dtype)
inp = inp * rescale.transpose(0, -1)
if is_conv:
# Transpose back: (N, H, W, ..., C) -> (N, C, H, W, ...)
inp = inp.transpose(1, -1)
return inp

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@ -1,7 +1,8 @@
import logging
from typing import Optional
from typing import Callable, Optional
import torch
import torch.nn.functional as F
import comfy.model_management
from .base import WeightAdapterBase, weight_decompose
@ -29,7 +30,14 @@ class GLoRAAdapter(WeightAdapterBase):
b1_name = "{}.b1.weight".format(x)
b2_name = "{}.b2.weight".format(x)
if a1_name in lora:
weights = (lora[a1_name], lora[a2_name], lora[b1_name], lora[b2_name], alpha, dora_scale)
weights = (
lora[a1_name],
lora[a2_name],
lora[b1_name],
lora[b2_name],
alpha,
dora_scale,
)
loaded_keys.add(a1_name)
loaded_keys.add(a2_name)
loaded_keys.add(b1_name)
@ -58,16 +66,28 @@ class GLoRAAdapter(WeightAdapterBase):
old_glora = True
if v[3].shape[0] == v[2].shape[1] == v[0].shape[1] == v[1].shape[0]:
if old_glora and v[1].shape[0] == weight.shape[0] and weight.shape[0] == weight.shape[1]:
if (
old_glora
and v[1].shape[0] == weight.shape[0]
and weight.shape[0] == weight.shape[1]
):
pass
else:
old_glora = False
rank = v[1].shape[0]
a1 = comfy.model_management.cast_to_device(v[0].flatten(start_dim=1), weight.device, intermediate_dtype)
a2 = comfy.model_management.cast_to_device(v[1].flatten(start_dim=1), weight.device, intermediate_dtype)
b1 = comfy.model_management.cast_to_device(v[2].flatten(start_dim=1), weight.device, intermediate_dtype)
b2 = comfy.model_management.cast_to_device(v[3].flatten(start_dim=1), weight.device, intermediate_dtype)
a1 = comfy.model_management.cast_to_device(
v[0].flatten(start_dim=1), weight.device, intermediate_dtype
)
a2 = comfy.model_management.cast_to_device(
v[1].flatten(start_dim=1), weight.device, intermediate_dtype
)
b1 = comfy.model_management.cast_to_device(
v[2].flatten(start_dim=1), weight.device, intermediate_dtype
)
b2 = comfy.model_management.cast_to_device(
v[3].flatten(start_dim=1), weight.device, intermediate_dtype
)
if v[4] is not None:
alpha = v[4] / rank
@ -76,18 +96,195 @@ class GLoRAAdapter(WeightAdapterBase):
try:
if old_glora:
lora_diff = (torch.mm(b2, b1) + torch.mm(torch.mm(weight.flatten(start_dim=1).to(dtype=intermediate_dtype), a2), a1)).reshape(weight.shape) #old lycoris glora
lora_diff = (
torch.mm(b2, b1)
+ torch.mm(
torch.mm(
weight.flatten(start_dim=1).to(dtype=intermediate_dtype), a2
),
a1,
)
).reshape(
weight.shape
) # old lycoris glora
else:
if weight.dim() > 2:
lora_diff = torch.einsum("o i ..., i j -> o j ...", torch.einsum("o i ..., i j -> o j ...", weight.to(dtype=intermediate_dtype), a1), a2).reshape(weight.shape)
lora_diff = torch.einsum(
"o i ..., i j -> o j ...",
torch.einsum(
"o i ..., i j -> o j ...",
weight.to(dtype=intermediate_dtype),
a1,
),
a2,
).reshape(weight.shape)
else:
lora_diff = torch.mm(torch.mm(weight.to(dtype=intermediate_dtype), a1), a2).reshape(weight.shape)
lora_diff = torch.mm(
torch.mm(weight.to(dtype=intermediate_dtype), a1), a2
).reshape(weight.shape)
lora_diff += torch.mm(b1, b2).reshape(weight.shape)
if dora_scale is not None:
weight = weight_decompose(dora_scale, weight, lora_diff, alpha, strength, intermediate_dtype, function)
weight = weight_decompose(
dora_scale,
weight,
lora_diff,
alpha,
strength,
intermediate_dtype,
function,
)
else:
weight += function(((strength * alpha) * lora_diff).type(weight.dtype))
except Exception as e:
logging.error("ERROR {} {} {}".format(self.name, key, e))
return weight
def _compute_paths(self, x: torch.Tensor):
"""
Compute A path and B path outputs for GLoRA bypass.
GLoRA: f(x) = Wx + WAx + Bx
- A path: a1(a2(x)) - modifies input to base forward
- B path: b1(b2(x)) - additive component
Note:
Does not access original model weights - bypass mode is designed
for quantized models where weights may not be accessible.
Returns: (a_out, b_out)
"""
v = self.weights
# v = (a1, a2, b1, b2, alpha, dora_scale)
a1 = v[0]
a2 = v[1]
b1 = v[2]
b2 = v[3]
alpha = v[4]
dtype = x.dtype
# Cast dtype (weights should already be on correct device from inject())
a1 = a1.to(dtype=dtype)
a2 = a2.to(dtype=dtype)
b1 = b1.to(dtype=dtype)
b2 = b2.to(dtype=dtype)
# Determine rank and scale
# Check for old vs new glora format
old_glora = False
if b2.shape[1] == b1.shape[0] == a1.shape[0] == a2.shape[1]:
rank = a1.shape[0]
old_glora = True
if b2.shape[0] == b1.shape[1] == a1.shape[1] == a2.shape[0]:
if old_glora and a2.shape[0] == x.shape[-1] and x.shape[-1] == x.shape[-1]:
pass
else:
old_glora = False
rank = a2.shape[0]
if alpha is not None:
scale = alpha / rank
else:
scale = 1.0
# Apply multiplier
multiplier = getattr(self, "multiplier", 1.0)
scale = scale * multiplier
# Use module info from bypass injection, not input tensor shape
is_conv = getattr(self, "is_conv", False)
conv_dim = getattr(self, "conv_dim", 0)
kw_dict = getattr(self, "kw_dict", {})
if is_conv:
# Conv case - conv_dim is 1/2/3 for conv1d/2d/3d
conv_fn = (F.conv1d, F.conv2d, F.conv3d)[conv_dim - 1]
# Get module's stride/padding for spatial dimension handling
module_stride = kw_dict.get("stride", (1,) * conv_dim)
module_padding = kw_dict.get("padding", (0,) * conv_dim)
kernel_size = getattr(self, "kernel_size", (1,) * conv_dim)
in_channels = getattr(self, "in_channels", None)
# Ensure weights are in conv shape
# a1, a2, b1 are always 1x1 kernels
if a1.ndim == 2:
a1 = a1.view(*a1.shape, *([1] * conv_dim))
if a2.ndim == 2:
a2 = a2.view(*a2.shape, *([1] * conv_dim))
if b1.ndim == 2:
b1 = b1.view(*b1.shape, *([1] * conv_dim))
# b2 has actual kernel_size (like LoRA down)
if b2.ndim == 2:
if in_channels is not None:
b2 = b2.view(b2.shape[0], in_channels, *kernel_size)
else:
b2 = b2.view(*b2.shape, *([1] * conv_dim))
# A path: a2(x) -> a1(...) - 1x1 convs, no stride/padding needed, a_out is added to x
a2_out = conv_fn(x, a2)
a_out = conv_fn(a2_out, a1) * scale
# B path: b2(x) with kernel/stride/padding -> b1(...) 1x1
b2_out = conv_fn(x, b2, stride=module_stride, padding=module_padding)
b_out = conv_fn(b2_out, b1) * scale
else:
# Linear case
if old_glora:
# Old format: a1 @ a2 @ x, b2 @ b1
a_out = F.linear(F.linear(x, a2), a1) * scale
b_out = F.linear(F.linear(x, b1), b2) * scale
else:
# New format: x @ a1 @ a2, b1 @ b2
a_out = F.linear(F.linear(x, a1), a2) * scale
b_out = F.linear(F.linear(x, b2), b1) * scale
return a_out, b_out
def bypass_forward(
self,
org_forward: Callable,
x: torch.Tensor,
*args,
**kwargs,
) -> torch.Tensor:
"""
GLoRA bypass forward: f(x + a(x)) + b(x)
Unlike standard adapters, GLoRA modifies the input to the base forward
AND adds the B path output.
Note:
Does not access original model weights - bypass mode is designed
for quantized models where weights may not be accessible.
Reference: LyCORIS GLoRAModule._bypass_forward
"""
a_out, b_out = self._compute_paths(x)
# Call base forward with modified input
base_out = org_forward(x + a_out, *args, **kwargs)
# Add B path
return base_out + b_out
def h(self, x: torch.Tensor, base_out: torch.Tensor) -> torch.Tensor:
"""
For GLoRA, h() returns the B path output.
Note:
GLoRA's full bypass requires overriding bypass_forward() since
it also modifies the input to org_forward. This h() is provided for
compatibility but bypass_forward() should be used for correct behavior.
Does not access original model weights - bypass mode is designed
for quantized models where weights may not be accessible.
Args:
x: Input tensor
base_out: Output from base forward (unused, for API consistency)
"""
_, b_out = self._compute_paths(x)
return b_out

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@ -1,11 +1,22 @@
import logging
from functools import cache
from typing import Optional
import torch
import torch.nn.functional as F
import comfy.model_management
from .base import WeightAdapterBase, WeightAdapterTrainBase, weight_decompose
@cache
def _warn_loha_bypass_inefficient():
"""One-time warning about LoHa bypass inefficiency."""
logging.warning(
"LoHa bypass mode is inefficient: full weight diff is computed each forward pass. "
"Consider using LoRA or LoKr for training with bypass mode."
)
class HadaWeight(torch.autograd.Function):
@staticmethod
def forward(ctx, w1u, w1d, w2u, w2d, scale=torch.tensor(1)):
@ -105,9 +116,19 @@ class LohaDiff(WeightAdapterTrainBase):
scale = self.alpha / self.rank
if self.use_tucker:
diff_weight = HadaWeightTucker.apply(self.hada_t1, self.hada_w1_a, self.hada_w1_b, self.hada_t2, self.hada_w2_a, self.hada_w2_b, scale)
diff_weight = HadaWeightTucker.apply(
self.hada_t1,
self.hada_w1_a,
self.hada_w1_b,
self.hada_t2,
self.hada_w2_a,
self.hada_w2_b,
scale,
)
else:
diff_weight = HadaWeight.apply(self.hada_w1_a, self.hada_w1_b, self.hada_w2_a, self.hada_w2_b, scale)
diff_weight = HadaWeight.apply(
self.hada_w1_a, self.hada_w1_b, self.hada_w2_a, self.hada_w2_b, scale
)
# Add the scaled difference to the original weight
weight = w.to(diff_weight) + diff_weight.reshape(w.shape)
@ -138,9 +159,7 @@ class LoHaAdapter(WeightAdapterBase):
mat4 = torch.empty(rank, in_dim, device=weight.device, dtype=torch.float32)
torch.nn.init.normal_(mat3, 0.1)
torch.nn.init.normal_(mat4, 0.01)
return LohaDiff(
(mat1, mat2, alpha, mat3, mat4, None, None, None)
)
return LohaDiff((mat1, mat2, alpha, mat3, mat4, None, None, None))
def to_train(self):
return LohaDiff(self.weights)
@ -172,7 +191,16 @@ class LoHaAdapter(WeightAdapterBase):
loaded_keys.add(hada_t1_name)
loaded_keys.add(hada_t2_name)
weights = (lora[hada_w1_a_name], lora[hada_w1_b_name], alpha, lora[hada_w2_a_name], lora[hada_w2_b_name], hada_t1, hada_t2, dora_scale)
weights = (
lora[hada_w1_a_name],
lora[hada_w1_b_name],
alpha,
lora[hada_w2_a_name],
lora[hada_w2_b_name],
hada_t1,
hada_t2,
dora_scale,
)
loaded_keys.add(hada_w1_a_name)
loaded_keys.add(hada_w1_b_name)
loaded_keys.add(hada_w2_a_name)
@ -203,30 +231,148 @@ class LoHaAdapter(WeightAdapterBase):
w2a = v[3]
w2b = v[4]
dora_scale = v[7]
if v[5] is not None: #cp decomposition
if v[5] is not None: # cp decomposition
t1 = v[5]
t2 = v[6]
m1 = torch.einsum('i j k l, j r, i p -> p r k l',
comfy.model_management.cast_to_device(t1, weight.device, intermediate_dtype),
comfy.model_management.cast_to_device(w1b, weight.device, intermediate_dtype),
comfy.model_management.cast_to_device(w1a, weight.device, intermediate_dtype))
m1 = torch.einsum(
"i j k l, j r, i p -> p r k l",
comfy.model_management.cast_to_device(
t1, weight.device, intermediate_dtype
),
comfy.model_management.cast_to_device(
w1b, weight.device, intermediate_dtype
),
comfy.model_management.cast_to_device(
w1a, weight.device, intermediate_dtype
),
)
m2 = torch.einsum('i j k l, j r, i p -> p r k l',
comfy.model_management.cast_to_device(t2, weight.device, intermediate_dtype),
comfy.model_management.cast_to_device(w2b, weight.device, intermediate_dtype),
comfy.model_management.cast_to_device(w2a, weight.device, intermediate_dtype))
m2 = torch.einsum(
"i j k l, j r, i p -> p r k l",
comfy.model_management.cast_to_device(
t2, weight.device, intermediate_dtype
),
comfy.model_management.cast_to_device(
w2b, weight.device, intermediate_dtype
),
comfy.model_management.cast_to_device(
w2a, weight.device, intermediate_dtype
),
)
else:
m1 = torch.mm(comfy.model_management.cast_to_device(w1a, weight.device, intermediate_dtype),
comfy.model_management.cast_to_device(w1b, weight.device, intermediate_dtype))
m2 = torch.mm(comfy.model_management.cast_to_device(w2a, weight.device, intermediate_dtype),
comfy.model_management.cast_to_device(w2b, weight.device, intermediate_dtype))
m1 = torch.mm(
comfy.model_management.cast_to_device(
w1a, weight.device, intermediate_dtype
),
comfy.model_management.cast_to_device(
w1b, weight.device, intermediate_dtype
),
)
m2 = torch.mm(
comfy.model_management.cast_to_device(
w2a, weight.device, intermediate_dtype
),
comfy.model_management.cast_to_device(
w2b, weight.device, intermediate_dtype
),
)
try:
lora_diff = (m1 * m2).reshape(weight.shape)
if dora_scale is not None:
weight = weight_decompose(dora_scale, weight, lora_diff, alpha, strength, intermediate_dtype, function)
weight = weight_decompose(
dora_scale,
weight,
lora_diff,
alpha,
strength,
intermediate_dtype,
function,
)
else:
weight += function(((strength * alpha) * lora_diff).type(weight.dtype))
except Exception as e:
logging.error("ERROR {} {} {}".format(self.name, key, e))
return weight
def h(self, x: torch.Tensor, base_out: torch.Tensor) -> torch.Tensor:
"""
Additive bypass component for LoHa: h(x) = diff_weight @ x
WARNING: Inefficient - computes full Hadamard product each forward.
Note:
Does not access original model weights - bypass mode is designed
for quantized models where weights may not be accessible.
Args:
x: Input tensor
base_out: Output from base forward (unused, for API consistency)
Reference: LyCORIS functional/loha.py bypass_forward_diff
"""
_warn_loha_bypass_inefficient()
# FUNC_LIST: [None, None, F.linear, F.conv1d, F.conv2d, F.conv3d]
FUNC_LIST = [None, None, F.linear, F.conv1d, F.conv2d, F.conv3d]
v = self.weights
# v[0]=w1a, v[1]=w1b, v[2]=alpha, v[3]=w2a, v[4]=w2b, v[5]=t1, v[6]=t2, v[7]=dora
w1a = v[0]
w1b = v[1]
alpha = v[2]
w2a = v[3]
w2b = v[4]
t1 = v[5]
t2 = v[6]
# Compute scale
rank = w1b.shape[0]
scale = (alpha / rank if alpha is not None else 1.0) * getattr(
self, "multiplier", 1.0
)
# Cast dtype
w1a = w1a.to(dtype=x.dtype)
w1b = w1b.to(dtype=x.dtype)
w2a = w2a.to(dtype=x.dtype)
w2b = w2b.to(dtype=x.dtype)
# Use module info from bypass injection, not weight dimension
is_conv = getattr(self, "is_conv", False)
conv_dim = getattr(self, "conv_dim", 0)
kw_dict = getattr(self, "kw_dict", {})
# Compute diff weight using Hadamard product
if t1 is not None and t2 is not None:
t1 = t1.to(dtype=x.dtype)
t2 = t2.to(dtype=x.dtype)
m1 = torch.einsum("i j k l, j r, i p -> p r k l", t1, w1b, w1a)
m2 = torch.einsum("i j k l, j r, i p -> p r k l", t2, w2b, w2a)
diff_weight = (m1 * m2) * scale
else:
m1 = w1a @ w1b
m2 = w2a @ w2b
diff_weight = (m1 * m2) * scale
if is_conv:
op = FUNC_LIST[conv_dim + 2]
kernel_size = getattr(self, "kernel_size", (1,) * conv_dim)
in_channels = getattr(self, "in_channels", None)
# Reshape 2D diff_weight to conv format using kernel_size
# diff_weight: [out_channels, in_channels * prod(kernel_size)] -> [out_channels, in_channels, *kernel_size]
if diff_weight.dim() == 2:
if in_channels is not None:
diff_weight = diff_weight.view(
diff_weight.shape[0], in_channels, *kernel_size
)
else:
diff_weight = diff_weight.view(
*diff_weight.shape, *([1] * conv_dim)
)
else:
op = F.linear
kw_dict = {}
return op(x, diff_weight, **kw_dict)

View File

@ -2,6 +2,7 @@ import logging
from typing import Optional
import torch
import torch.nn.functional as F
import comfy.model_management
from .base import (
WeightAdapterBase,
@ -14,7 +15,17 @@ from .base import (
class LokrDiff(WeightAdapterTrainBase):
def __init__(self, weights):
super().__init__()
(lokr_w1, lokr_w2, alpha, lokr_w1_a, lokr_w1_b, lokr_w2_a, lokr_w2_b, lokr_t2, dora_scale) = weights
(
lokr_w1,
lokr_w2,
alpha,
lokr_w1_a,
lokr_w1_b,
lokr_w2_a,
lokr_w2_b,
lokr_t2,
dora_scale,
) = weights
self.use_tucker = False
if lokr_w1_a is not None:
_, rank_a = lokr_w1_a.shape[0], lokr_w1_a.shape[1]
@ -57,10 +68,10 @@ class LokrDiff(WeightAdapterTrainBase):
if self.w2_rebuild:
if self.use_tucker:
w2 = torch.einsum(
'i j k l, j r, i p -> p r k l',
"i j k l, j r, i p -> p r k l",
self.lokr_t2,
self.lokr_w2_b,
self.lokr_w2_a
self.lokr_w2_a,
)
else:
w2 = self.lokr_w2_a @ self.lokr_w2_b
@ -69,9 +80,89 @@ class LokrDiff(WeightAdapterTrainBase):
return self.lokr_w2
def __call__(self, w):
diff = torch.kron(self.w1, self.w2)
w1 = self.w1
w2 = self.w2
# Unsqueeze w1 to match w2 dims for proper kron product (like LyCORIS make_kron)
for _ in range(w2.dim() - w1.dim()):
w1 = w1.unsqueeze(-1)
diff = torch.kron(w1, w2)
return w + diff.reshape(w.shape).to(w)
def h(self, x: torch.Tensor, base_out: torch.Tensor) -> torch.Tensor:
"""
Additive bypass component for LoKr training: efficient Kronecker product.
Uses w1/w2 properties which handle both direct and decomposed cases.
For create_train (direct w1/w2), no alpha scaling in properties.
For to_train (decomposed), alpha/rank scaling is in properties.
Args:
x: Input tensor
base_out: Output from base forward (unused, for API consistency)
"""
# Get w1, w2 from properties (handles rebuild vs direct)
w1 = self.w1
w2 = self.w2
# Multiplier from bypass injection
multiplier = getattr(self, "multiplier", 1.0)
# Get module info from bypass injection
is_conv = getattr(self, "is_conv", False)
conv_dim = getattr(self, "conv_dim", 0)
kw_dict = getattr(self, "kw_dict", {})
# Efficient Kronecker application without materializing full weight
# kron(w1, w2) @ x can be computed as nested operations
# w1: [out_l, in_m], w2: [out_k, in_n, *k_size]
# Full weight would be [out_l*out_k, in_m*in_n, *k_size]
uq = w1.size(1) # in_m - inner grouping dimension
if is_conv:
conv_fn = (F.conv1d, F.conv2d, F.conv3d)[conv_dim - 1]
B, C_in, *spatial = x.shape
# Reshape input for grouped application: [B * uq, C_in // uq, *spatial]
h_in_group = x.reshape(B * uq, -1, *spatial)
# Ensure w2 has conv dims
if w2.dim() == 2:
w2 = w2.view(*w2.shape, *([1] * conv_dim))
# Apply w2 path with stride/padding
hb = conv_fn(h_in_group, w2, **kw_dict)
# Reshape for cross-group operation
hb = hb.view(B, -1, *hb.shape[1:])
h_cross = hb.transpose(1, -1)
# Apply w1 (always 2D, applied as linear on channel dim)
hc = F.linear(h_cross, w1)
hc = hc.transpose(1, -1)
# Reshape to output
out = hc.reshape(B, -1, *hc.shape[3:])
else:
# Linear case
# Reshape input: [..., in_m * in_n] -> [..., uq (in_m), in_n]
h_in_group = x.reshape(*x.shape[:-1], uq, -1)
# Apply w2: [..., uq, in_n] @ [out_k, in_n].T -> [..., uq, out_k]
hb = F.linear(h_in_group, w2)
# Transpose for w1: [..., uq, out_k] -> [..., out_k, uq]
h_cross = hb.transpose(-1, -2)
# Apply w1: [..., out_k, uq] @ [out_l, uq].T -> [..., out_k, out_l]
hc = F.linear(h_cross, w1)
# Transpose back and flatten: [..., out_k, out_l] -> [..., out_l * out_k]
hc = hc.transpose(-1, -2)
out = hc.reshape(*hc.shape[:-2], -1)
return out * multiplier
def passive_memory_usage(self):
return sum(param.numel() * param.element_size() for param in self.parameters())
@ -86,16 +177,22 @@ class LoKrAdapter(WeightAdapterBase):
@classmethod
def create_train(cls, weight, rank=1, alpha=1.0):
out_dim = weight.shape[0]
in_dim = weight.shape[1:].numel()
out1, out2 = factorization(out_dim, rank)
in1, in2 = factorization(in_dim, rank)
mat1 = torch.empty(out1, in1, device=weight.device, dtype=torch.float32)
mat2 = torch.empty(out2, in2, device=weight.device, dtype=torch.float32)
in_dim = weight.shape[1] # Just in_channels, not flattened with kernel
k_size = weight.shape[2:] if weight.dim() > 2 else ()
out_l, out_k = factorization(out_dim, rank)
in_m, in_n = factorization(in_dim, rank)
# w1: [out_l, in_m]
mat1 = torch.empty(out_l, in_m, device=weight.device, dtype=torch.float32)
# w2: [out_k, in_n, *k_size] for conv, [out_k, in_n] for linear
mat2 = torch.empty(
out_k, in_n, *k_size, device=weight.device, dtype=torch.float32
)
torch.nn.init.kaiming_uniform_(mat2, a=5**0.5)
torch.nn.init.constant_(mat1, 0.0)
return LokrDiff(
(mat1, mat2, alpha, None, None, None, None, None, None)
)
return LokrDiff((mat1, mat2, alpha, None, None, None, None, None, None))
def to_train(self):
return LokrDiff(self.weights)
@ -154,8 +251,23 @@ class LoKrAdapter(WeightAdapterBase):
lokr_t2 = lora[lokr_t2_name]
loaded_keys.add(lokr_t2_name)
if (lokr_w1 is not None) or (lokr_w2 is not None) or (lokr_w1_a is not None) or (lokr_w2_a is not None):
weights = (lokr_w1, lokr_w2, alpha, lokr_w1_a, lokr_w1_b, lokr_w2_a, lokr_w2_b, lokr_t2, dora_scale)
if (
(lokr_w1 is not None)
or (lokr_w2 is not None)
or (lokr_w1_a is not None)
or (lokr_w2_a is not None)
):
weights = (
lokr_w1,
lokr_w2,
alpha,
lokr_w1_a,
lokr_w1_b,
lokr_w2_a,
lokr_w2_b,
lokr_t2,
dora_scale,
)
return cls(loaded_keys, weights)
else:
return None
@ -184,23 +296,47 @@ class LoKrAdapter(WeightAdapterBase):
if w1 is None:
dim = w1_b.shape[0]
w1 = torch.mm(comfy.model_management.cast_to_device(w1_a, weight.device, intermediate_dtype),
comfy.model_management.cast_to_device(w1_b, weight.device, intermediate_dtype))
w1 = torch.mm(
comfy.model_management.cast_to_device(
w1_a, weight.device, intermediate_dtype
),
comfy.model_management.cast_to_device(
w1_b, weight.device, intermediate_dtype
),
)
else:
w1 = comfy.model_management.cast_to_device(w1, weight.device, intermediate_dtype)
w1 = comfy.model_management.cast_to_device(
w1, weight.device, intermediate_dtype
)
if w2 is None:
dim = w2_b.shape[0]
if t2 is None:
w2 = torch.mm(comfy.model_management.cast_to_device(w2_a, weight.device, intermediate_dtype),
comfy.model_management.cast_to_device(w2_b, weight.device, intermediate_dtype))
w2 = torch.mm(
comfy.model_management.cast_to_device(
w2_a, weight.device, intermediate_dtype
),
comfy.model_management.cast_to_device(
w2_b, weight.device, intermediate_dtype
),
)
else:
w2 = torch.einsum('i j k l, j r, i p -> p r k l',
comfy.model_management.cast_to_device(t2, weight.device, intermediate_dtype),
comfy.model_management.cast_to_device(w2_b, weight.device, intermediate_dtype),
comfy.model_management.cast_to_device(w2_a, weight.device, intermediate_dtype))
w2 = torch.einsum(
"i j k l, j r, i p -> p r k l",
comfy.model_management.cast_to_device(
t2, weight.device, intermediate_dtype
),
comfy.model_management.cast_to_device(
w2_b, weight.device, intermediate_dtype
),
comfy.model_management.cast_to_device(
w2_a, weight.device, intermediate_dtype
),
)
else:
w2 = comfy.model_management.cast_to_device(w2, weight.device, intermediate_dtype)
w2 = comfy.model_management.cast_to_device(
w2, weight.device, intermediate_dtype
)
if len(w2.shape) == 4:
w1 = w1.unsqueeze(2).unsqueeze(2)
@ -212,9 +348,134 @@ class LoKrAdapter(WeightAdapterBase):
try:
lora_diff = torch.kron(w1, w2).reshape(weight.shape)
if dora_scale is not None:
weight = weight_decompose(dora_scale, weight, lora_diff, alpha, strength, intermediate_dtype, function)
weight = weight_decompose(
dora_scale,
weight,
lora_diff,
alpha,
strength,
intermediate_dtype,
function,
)
else:
weight += function(((strength * alpha) * lora_diff).type(weight.dtype))
except Exception as e:
logging.error("ERROR {} {} {}".format(self.name, key, e))
return weight
def h(self, x: torch.Tensor, base_out: torch.Tensor) -> torch.Tensor:
"""
Additive bypass component for LoKr: efficient Kronecker product application.
Note:
Does not access original model weights - bypass mode is designed
for quantized models where weights may not be accessible.
Args:
x: Input tensor
base_out: Output from base forward (unused, for API consistency)
Reference: LyCORIS functional/lokr.py bypass_forward_diff
"""
# FUNC_LIST: [None, None, F.linear, F.conv1d, F.conv2d, F.conv3d]
FUNC_LIST = [None, None, F.linear, F.conv1d, F.conv2d, F.conv3d]
v = self.weights
# v[0]=w1, v[1]=w2, v[2]=alpha, v[3]=w1_a, v[4]=w1_b, v[5]=w2_a, v[6]=w2_b, v[7]=t2, v[8]=dora
w1 = v[0]
w2 = v[1]
alpha = v[2]
w1_a = v[3]
w1_b = v[4]
w2_a = v[5]
w2_b = v[6]
t2 = v[7]
use_w1 = w1 is not None
use_w2 = w2 is not None
tucker = t2 is not None
# Use module info from bypass injection, not weight dimension
is_conv = getattr(self, "is_conv", False)
conv_dim = getattr(self, "conv_dim", 0)
kw_dict = getattr(self, "kw_dict", {}) if is_conv else {}
if is_conv:
op = FUNC_LIST[conv_dim + 2]
else:
op = F.linear
# Determine rank and scale
rank = w1_b.size(0) if not use_w1 else w2_b.size(0) if not use_w2 else alpha
scale = (alpha / rank if alpha is not None else 1.0) * getattr(
self, "multiplier", 1.0
)
# Build c (w1)
if use_w1:
c = w1.to(dtype=x.dtype)
else:
c = w1_a.to(dtype=x.dtype) @ w1_b.to(dtype=x.dtype)
uq = c.size(1)
# Build w2 components
if use_w2:
ba = w2.to(dtype=x.dtype)
else:
a = w2_b.to(dtype=x.dtype)
b = w2_a.to(dtype=x.dtype)
if is_conv:
if tucker:
# Tucker: a, b get 1s appended (kernel is in t2)
if a.dim() == 2:
a = a.view(*a.shape, *([1] * conv_dim))
if b.dim() == 2:
b = b.view(*b.shape, *([1] * conv_dim))
else:
# Non-tucker conv: b may need 1s appended
if b.dim() == 2:
b = b.view(*b.shape, *([1] * conv_dim))
# Reshape input by uq groups
if is_conv:
B, _, *rest = x.shape
h_in_group = x.reshape(B * uq, -1, *rest)
else:
h_in_group = x.reshape(*x.shape[:-1], uq, -1)
# Apply w2 path
if use_w2:
hb = op(h_in_group, ba, **kw_dict)
else:
if is_conv:
if tucker:
t = t2.to(dtype=x.dtype)
if t.dim() == 2:
t = t.view(*t.shape, *([1] * conv_dim))
ha = op(h_in_group, a)
ht = op(ha, t, **kw_dict)
hb = op(ht, b)
else:
ha = op(h_in_group, a, **kw_dict)
hb = op(ha, b)
else:
ha = op(h_in_group, a)
hb = op(ha, b)
# Reshape and apply c (w1)
if is_conv:
hb = hb.view(B, -1, *hb.shape[1:])
h_cross_group = hb.transpose(1, -1)
else:
h_cross_group = hb.transpose(-1, -2)
hc = F.linear(h_cross_group, c)
if is_conv:
hc = hc.transpose(1, -1)
out = hc.reshape(B, -1, *hc.shape[3:])
else:
hc = hc.transpose(-1, -2)
out = hc.reshape(*hc.shape[:-2], -1)
return out * scale

View File

@ -2,6 +2,7 @@ import logging
from typing import Optional
import torch
import torch.nn.functional as F
import comfy.model_management
from .base import (
WeightAdapterBase,
@ -20,11 +21,7 @@ class LoraDiff(WeightAdapterTrainBase):
rank, in_dim = mat2.shape[0], mat2.shape[1]
if mid is not None:
convdim = mid.ndim - 2
layer = (
torch.nn.Conv1d,
torch.nn.Conv2d,
torch.nn.Conv3d
)[convdim]
layer = (torch.nn.Conv1d, torch.nn.Conv2d, torch.nn.Conv3d)[convdim]
else:
layer = torch.nn.Linear
self.lora_up = layer(rank, out_dim, bias=False)
@ -51,6 +48,78 @@ class LoraDiff(WeightAdapterTrainBase):
weight = w + scale * diff.reshape(w.shape)
return weight.to(org_dtype)
def h(self, x: torch.Tensor, base_out: torch.Tensor) -> torch.Tensor:
"""
Additive bypass component for LoRA training: h(x) = up(down(x)) * scale
Simple implementation using the nn.Module weights directly.
No mid/dora/reshape branches (create_train doesn't create them).
Args:
x: Input tensor
base_out: Output from base forward (unused, for API consistency)
"""
# Compute scale = alpha / rank * multiplier
scale = (self.alpha / self.rank) * getattr(self, "multiplier", 1.0)
# Get module info from bypass injection
is_conv = getattr(self, "is_conv", False)
conv_dim = getattr(self, "conv_dim", 0)
kw_dict = getattr(self, "kw_dict", {})
# Get weights (keep in original dtype for numerical stability)
down_weight = self.lora_down.weight
up_weight = self.lora_up.weight
if is_conv:
# Conv path: use functional conv
# conv_dim: 1=conv1d, 2=conv2d, 3=conv3d
conv_fn = (F.conv1d, F.conv2d, F.conv3d)[conv_dim - 1]
# Reshape 2D weights to conv format if needed
# down: [rank, in_features] -> [rank, in_channels, *kernel_size]
# up: [out_features, rank] -> [out_features, rank, 1, 1, ...]
if down_weight.dim() == 2:
kernel_size = getattr(self, "kernel_size", (1,) * conv_dim)
in_channels = getattr(self, "in_channels", None)
if in_channels is not None:
down_weight = down_weight.view(
down_weight.shape[0], in_channels, *kernel_size
)
else:
# Fallback: assume 1x1 kernel
down_weight = down_weight.view(
*down_weight.shape, *([1] * conv_dim)
)
if up_weight.dim() == 2:
# up always uses 1x1 kernel
up_weight = up_weight.view(*up_weight.shape, *([1] * conv_dim))
# down conv uses stride/padding from module, up is 1x1
hidden = conv_fn(x, down_weight, **kw_dict)
# mid layer if exists (tucker decomposition)
if self.lora_mid is not None:
mid_weight = self.lora_mid.weight
if mid_weight.dim() == 2:
mid_weight = mid_weight.view(*mid_weight.shape, *([1] * conv_dim))
hidden = conv_fn(hidden, mid_weight)
# up conv is always 1x1 (no stride/padding)
out = conv_fn(hidden, up_weight)
else:
# Linear path: simple matmul chain
hidden = F.linear(x, down_weight)
# mid layer if exists
if self.lora_mid is not None:
mid_weight = self.lora_mid.weight
hidden = F.linear(hidden, mid_weight)
out = F.linear(hidden, up_weight)
return out * scale
def passive_memory_usage(self):
return sum(param.numel() * param.element_size() for param in self.parameters())
@ -70,9 +139,7 @@ class LoRAAdapter(WeightAdapterBase):
mat2 = torch.empty(rank, in_dim, device=weight.device, dtype=torch.float32)
torch.nn.init.kaiming_uniform_(mat1, a=5**0.5)
torch.nn.init.constant_(mat2, 0.0)
return LoraDiff(
(mat1, mat2, alpha, None, None, None)
)
return LoraDiff((mat1, mat2, alpha, None, None, None))
def to_train(self):
return LoraDiff(self.weights)
@ -210,3 +277,85 @@ class LoRAAdapter(WeightAdapterBase):
except Exception as e:
logging.error("ERROR {} {} {}".format(self.name, key, e))
return weight
def h(self, x: torch.Tensor, base_out: torch.Tensor) -> torch.Tensor:
"""
Additive bypass component for LoRA: h(x) = up(down(x)) * scale
Note:
Does not access original model weights - bypass mode is designed
for quantized models where weights may not be accessible.
Args:
x: Input tensor
base_out: Output from base forward (unused, for API consistency)
Reference: LyCORIS functional/locon.py bypass_forward_diff
"""
# FUNC_LIST: [None, None, F.linear, F.conv1d, F.conv2d, F.conv3d]
FUNC_LIST = [None, None, F.linear, F.conv1d, F.conv2d, F.conv3d]
v = self.weights
# v[0]=up, v[1]=down, v[2]=alpha, v[3]=mid, v[4]=dora_scale, v[5]=reshape
up = v[0]
down = v[1]
alpha = v[2]
mid = v[3]
# Compute scale = alpha / rank
rank = down.shape[0]
if alpha is not None:
scale = alpha / rank
else:
scale = 1.0
scale = scale * getattr(self, "multiplier", 1.0)
# Cast dtype
up = up.to(dtype=x.dtype)
down = down.to(dtype=x.dtype)
# Use module info from bypass injection, not weight dimension
is_conv = getattr(self, "is_conv", False)
conv_dim = getattr(self, "conv_dim", 0)
kw_dict = getattr(self, "kw_dict", {})
if is_conv:
op = FUNC_LIST[
conv_dim + 2
] # conv_dim 1->conv1d(3), 2->conv2d(4), 3->conv3d(5)
kernel_size = getattr(self, "kernel_size", (1,) * conv_dim)
in_channels = getattr(self, "in_channels", None)
# Reshape 2D weights to conv format using kernel_size
# down: [rank, in_channels * prod(kernel_size)] -> [rank, in_channels, *kernel_size]
# up: [out_channels, rank] -> [out_channels, rank, 1, 1, ...] (1x1 kernel)
if down.dim() == 2:
# down.shape[1] = in_channels * prod(kernel_size)
if in_channels is not None:
down = down.view(down.shape[0], in_channels, *kernel_size)
else:
# Fallback: assume 1x1 kernel if in_channels unknown
down = down.view(*down.shape, *([1] * conv_dim))
if up.dim() == 2:
# up always uses 1x1 kernel
up = up.view(*up.shape, *([1] * conv_dim))
if mid is not None:
mid = mid.to(dtype=x.dtype)
if mid.dim() == 2:
mid = mid.view(*mid.shape, *([1] * conv_dim))
else:
op = F.linear
kw_dict = {} # linear doesn't take stride/padding
# Simple chain: down -> mid (if tucker) -> up
if mid is not None:
if not is_conv:
mid = mid.to(dtype=x.dtype)
hidden = op(x, down)
hidden = op(hidden, mid, **kw_dict)
out = op(hidden, up)
else:
hidden = op(x, down, **kw_dict)
out = op(hidden, up)
return out * scale

View File

@ -3,13 +3,18 @@ from typing import Optional
import torch
import comfy.model_management
from .base import WeightAdapterBase, WeightAdapterTrainBase, weight_decompose, factorization
from .base import (
WeightAdapterBase,
WeightAdapterTrainBase,
weight_decompose,
factorization,
)
class OFTDiff(WeightAdapterTrainBase):
def __init__(self, weights):
super().__init__()
# Unpack weights tuple from LoHaAdapter
# Unpack weights tuple from OFTAdapter
blocks, rescale, alpha, _ = weights
# Create trainable parameters
@ -52,6 +57,78 @@ class OFTDiff(WeightAdapterTrainBase):
weight = self.rescale * weight
return weight.to(org_dtype)
def _get_orthogonal_matrix(self, device, dtype):
"""Compute the orthogonal rotation matrix R from OFT blocks."""
blocks = self.oft_blocks.to(device=device, dtype=dtype)
I = torch.eye(self.block_size, device=device, dtype=dtype)
# Q = blocks - blocks^T (skew-symmetric)
q = blocks - blocks.transpose(1, 2)
normed_q = q
# Apply constraint if set
if self.constraint:
q_norm = torch.norm(q) + 1e-8
if q_norm > self.constraint:
normed_q = q * self.constraint / q_norm
# Cayley transform: R = (I + Q)(I - Q)^-1
r = (I + normed_q) @ (I - normed_q).float().inverse()
return r.to(dtype)
def h(self, x: torch.Tensor, base_out: torch.Tensor) -> torch.Tensor:
"""
OFT has no additive component - returns zeros matching base_out shape.
OFT only transforms the output via g(), it doesn't add to it.
"""
return torch.zeros_like(base_out)
def g(self, y: torch.Tensor) -> torch.Tensor:
"""
Output transformation for OFT: applies orthogonal rotation.
OFT transforms output channels using block-diagonal orthogonal matrices.
"""
r = self._get_orthogonal_matrix(y.device, y.dtype)
# Apply multiplier to interpolate between identity and full transform
multiplier = getattr(self, "multiplier", 1.0)
I = torch.eye(self.block_size, device=y.device, dtype=y.dtype)
r = r * multiplier + (1 - multiplier) * I
# Use module info from bypass injection
is_conv = getattr(self, "is_conv", y.dim() > 2)
if is_conv:
# Conv output: (N, C, H, W, ...) -> transpose to (N, H, W, ..., C)
y = y.transpose(1, -1)
# y now has channels in last dim
*batch_shape, out_features = y.shape
# Reshape to apply block-diagonal transform
# (*, out_features) -> (*, block_num, block_size)
y_blocked = y.reshape(*batch_shape, self.block_num, self.block_size)
# Apply orthogonal transform: R @ y for each block
# r: (block_num, block_size, block_size), y_blocked: (*, block_num, block_size)
out_blocked = torch.einsum("k n m, ... k n -> ... k m", r, y_blocked)
# Reshape back: (*, block_num, block_size) -> (*, out_features)
out = out_blocked.reshape(*batch_shape, out_features)
# Apply rescale if present
if self.rescaled:
rescale = self.rescale.to(device=y.device, dtype=y.dtype)
out = out * rescale.view(-1)
if is_conv:
# Transpose back: (N, H, W, ..., C) -> (N, C, H, W, ...)
out = out.transpose(1, -1)
return out
def passive_memory_usage(self):
"""Calculates memory usage of the trainable parameters."""
return sum(param.numel() * param.element_size() for param in self.parameters())
@ -68,10 +145,10 @@ class OFTAdapter(WeightAdapterBase):
def create_train(cls, weight, rank=1, alpha=1.0):
out_dim = weight.shape[0]
block_size, block_num = factorization(out_dim, rank)
block = torch.zeros(block_num, block_size, block_size, device=weight.device, dtype=torch.float32)
return OFTDiff(
(block, None, alpha, None)
block = torch.zeros(
block_num, block_size, block_size, device=weight.device, dtype=torch.float32
)
return OFTDiff((block, None, alpha, None))
def to_train(self):
return OFTDiff(self.weights)
@ -127,9 +204,13 @@ class OFTAdapter(WeightAdapterBase):
alpha = 0
dora_scale = v[3]
blocks = comfy.model_management.cast_to_device(blocks, weight.device, intermediate_dtype)
blocks = comfy.model_management.cast_to_device(
blocks, weight.device, intermediate_dtype
)
if rescale is not None:
rescale = comfy.model_management.cast_to_device(rescale, weight.device, intermediate_dtype)
rescale = comfy.model_management.cast_to_device(
rescale, weight.device, intermediate_dtype
)
block_num, block_size, *_ = blocks.shape
@ -139,23 +220,108 @@ class OFTAdapter(WeightAdapterBase):
# for Q = -Q^T
q = blocks - blocks.transpose(1, 2)
normed_q = q
if alpha > 0: # alpha in oft/boft is for constraint
if alpha > 0: # alpha in oft/boft is for constraint
q_norm = torch.norm(q) + 1e-8
if q_norm > alpha:
normed_q = q * alpha / q_norm
# use float() to prevent unsupported type in .inverse()
r = (I + normed_q) @ (I - normed_q).float().inverse()
r = r.to(weight)
# Create I in weight's dtype for the einsum
I_w = torch.eye(block_size, device=weight.device, dtype=weight.dtype)
_, *shape = weight.shape
lora_diff = torch.einsum(
"k n m, k n ... -> k m ...",
(r * strength) - strength * I,
(r * strength) - strength * I_w,
weight.view(block_num, block_size, *shape),
).view(-1, *shape)
if dora_scale is not None:
weight = weight_decompose(dora_scale, weight, lora_diff, alpha, strength, intermediate_dtype, function)
weight = weight_decompose(
dora_scale,
weight,
lora_diff,
alpha,
strength,
intermediate_dtype,
function,
)
else:
weight += function((strength * lora_diff).type(weight.dtype))
except Exception as e:
logging.error("ERROR {} {} {}".format(self.name, key, e))
return weight
def _get_orthogonal_matrix(self, device, dtype):
"""Compute the orthogonal rotation matrix R from OFT blocks."""
v = self.weights
blocks = v[0].to(device=device, dtype=dtype)
alpha = v[2]
if alpha is None:
alpha = 0
block_num, block_size, _ = blocks.shape
I = torch.eye(block_size, device=device, dtype=dtype)
# Q = blocks - blocks^T (skew-symmetric)
q = blocks - blocks.transpose(1, 2)
normed_q = q
# Apply constraint if alpha > 0
if alpha > 0:
q_norm = torch.norm(q) + 1e-8
if q_norm > alpha:
normed_q = q * alpha / q_norm
# Cayley transform: R = (I + Q)(I - Q)^-1
r = (I + normed_q) @ (I - normed_q).float().inverse()
return r, block_num, block_size
def g(self, y: torch.Tensor) -> torch.Tensor:
"""
Output transformation for OFT: applies orthogonal rotation to output.
OFT transforms the output channels using block-diagonal orthogonal matrices.
Reference: LyCORIS DiagOFTModule._bypass_forward
"""
v = self.weights
rescale = v[1]
r, block_num, block_size = self._get_orthogonal_matrix(y.device, y.dtype)
# Apply multiplier to interpolate between identity and full transform
multiplier = getattr(self, "multiplier", 1.0)
I = torch.eye(block_size, device=y.device, dtype=y.dtype)
r = r * multiplier + (1 - multiplier) * I
# Use module info from bypass injection to determine conv vs linear
is_conv = getattr(self, "is_conv", y.dim() > 2)
if is_conv:
# Conv output: (N, C, H, W, ...) -> transpose to (N, H, W, ..., C)
y = y.transpose(1, -1)
# y now has channels in last dim
*batch_shape, out_features = y.shape
# Reshape to apply block-diagonal transform
# (*, out_features) -> (*, block_num, block_size)
y_blocked = y.view(*batch_shape, block_num, block_size)
# Apply orthogonal transform: R @ y for each block
# r: (block_num, block_size, block_size), y_blocked: (*, block_num, block_size)
out_blocked = torch.einsum("k n m, ... k n -> ... k m", r, y_blocked)
# Reshape back: (*, block_num, block_size) -> (*, out_features)
out = out_blocked.view(*batch_shape, out_features)
# Apply rescale if present
if rescale is not None:
rescale = rescale.to(device=y.device, dtype=y.dtype)
out = out * rescale.view(-1)
if is_conv:
# Transpose back: (N, H, W, ..., C) -> (N, C, H, W, ...)
out = out.transpose(1, -1)
return out