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DiffSynth-Studio/diffsynth/lora/flux_lora.py
2025-07-03 18:49:46 +08:00

143 lines
7.7 KiB
Python

import torch, math
from diffsynth.lora import GeneralLoRALoader
from diffsynth.models.lora import FluxLoRAFromCivitai
class FluxLoRALoader(GeneralLoRALoader):
def __init__(self, device="cpu", torch_dtype=torch.float32):
super().__init__(device=device, torch_dtype=torch_dtype)
def load(self, model: torch.nn.Module, state_dict_lora, alpha=1.0):
super().load(model, state_dict_lora, alpha)
def convert_state_dict(self, state_dict):
# TODO: support other lora format
rename_dict = {
"lora_unet_double_blocks_blockid_img_mod_lin.lora_down.weight": "blocks.blockid.norm1_a.linear.lora_A.default.weight",
"lora_unet_double_blocks_blockid_img_mod_lin.lora_up.weight": "blocks.blockid.norm1_a.linear.lora_B.default.weight",
"lora_unet_double_blocks_blockid_txt_mod_lin.lora_down.weight": "blocks.blockid.norm1_b.linear.lora_A.default.weight",
"lora_unet_double_blocks_blockid_txt_mod_lin.lora_up.weight": "blocks.blockid.norm1_b.linear.lora_B.default.weight",
"lora_unet_double_blocks_blockid_img_attn_qkv.lora_down.weight": "blocks.blockid.attn.a_to_qkv.lora_A.default.weight",
"lora_unet_double_blocks_blockid_img_attn_qkv.lora_up.weight": "blocks.blockid.attn.a_to_qkv.lora_B.default.weight",
"lora_unet_double_blocks_blockid_txt_attn_qkv.lora_down.weight": "blocks.blockid.attn.b_to_qkv.lora_A.default.weight",
"lora_unet_double_blocks_blockid_txt_attn_qkv.lora_up.weight": "blocks.blockid.attn.b_to_qkv.lora_B.default.weight",
"lora_unet_double_blocks_blockid_img_attn_proj.lora_down.weight": "blocks.blockid.attn.a_to_out.lora_A.default.weight",
"lora_unet_double_blocks_blockid_img_attn_proj.lora_up.weight": "blocks.blockid.attn.a_to_out.lora_B.default.weight",
"lora_unet_double_blocks_blockid_txt_attn_proj.lora_down.weight": "blocks.blockid.attn.b_to_out.lora_A.default.weight",
"lora_unet_double_blocks_blockid_txt_attn_proj.lora_up.weight": "blocks.blockid.attn.b_to_out.lora_B.default.weight",
"lora_unet_double_blocks_blockid_img_mlp_0.lora_down.weight": "blocks.blockid.ff_a.0.lora_A.default.weight",
"lora_unet_double_blocks_blockid_img_mlp_0.lora_up.weight": "blocks.blockid.ff_a.0.lora_B.default.weight",
"lora_unet_double_blocks_blockid_img_mlp_2.lora_down.weight": "blocks.blockid.ff_a.2.lora_A.default.weight",
"lora_unet_double_blocks_blockid_img_mlp_2.lora_up.weight": "blocks.blockid.ff_a.2.lora_B.default.weight",
"lora_unet_double_blocks_blockid_txt_mlp_0.lora_down.weight": "blocks.blockid.ff_b.0.lora_A.default.weight",
"lora_unet_double_blocks_blockid_txt_mlp_0.lora_up.weight": "blocks.blockid.ff_b.0.lora_B.default.weight",
"lora_unet_double_blocks_blockid_txt_mlp_2.lora_down.weight": "blocks.blockid.ff_b.2.lora_A.default.weight",
"lora_unet_double_blocks_blockid_txt_mlp_2.lora_up.weight": "blocks.blockid.ff_b.2.lora_B.default.weight",
"lora_unet_single_blocks_blockid_modulation_lin.lora_down.weight": "single_blocks.blockid.norm.linear.lora_A.default.weight",
"lora_unet_single_blocks_blockid_modulation_lin.lora_up.weight": "single_blocks.blockid.norm.linear.lora_B.default.weight",
"lora_unet_single_blocks_blockid_linear1.lora_down.weight": "single_blocks.blockid.to_qkv_mlp.lora_A.default.weight",
"lora_unet_single_blocks_blockid_linear1.lora_up.weight": "single_blocks.blockid.to_qkv_mlp.lora_B.default.weight",
"lora_unet_single_blocks_blockid_linear2.lora_down.weight": "single_blocks.blockid.proj_out.lora_A.default.weight",
"lora_unet_single_blocks_blockid_linear2.lora_up.weight": "single_blocks.blockid.proj_out.lora_B.default.weight",
}
def guess_block_id(name):
names = name.split("_")
for i in names:
if i.isdigit():
return i, name.replace(f"_{i}_", "_blockid_")
return None, None
def guess_alpha(state_dict):
for name, param in state_dict.items():
if ".alpha" in name:
name_ = name.replace(".alpha", ".lora_down.weight")
if name_ in state_dict:
lora_alpha = param.item() / state_dict[name_].shape[0]
lora_alpha = math.sqrt(lora_alpha)
return lora_alpha
return 1
alpha = guess_alpha(state_dict)
state_dict_ = {}
for name, param in state_dict.items():
block_id, source_name = guess_block_id(name)
if alpha != 1:
param *= alpha
if source_name in rename_dict:
target_name = rename_dict[source_name]
target_name = target_name.replace(".blockid.", f".{block_id}.")
state_dict_[target_name] = param
else:
state_dict_[name] = param
return state_dict_
class LoraMerger(torch.nn.Module):
def __init__(self, dim):
super().__init__()
self.weight_base = torch.nn.Parameter(torch.randn((dim,)))
self.weight_lora = torch.nn.Parameter(torch.randn((dim,)))
self.weight_cross = torch.nn.Parameter(torch.randn((dim,)))
self.weight_out = torch.nn.Parameter(torch.ones((dim,)))
self.bias = torch.nn.Parameter(torch.randn((dim,)))
self.activation = torch.nn.Sigmoid()
self.norm_base = torch.nn.LayerNorm(dim, eps=1e-5)
self.norm_lora = torch.nn.LayerNorm(dim, eps=1e-5)
def forward(self, base_output, lora_outputs):
norm_base_output = self.norm_base(base_output)
norm_lora_outputs = self.norm_lora(lora_outputs)
gate = self.activation(
norm_base_output * self.weight_base \
+ norm_lora_outputs * self.weight_lora \
+ norm_base_output * norm_lora_outputs * self.weight_cross + self.bias
)
output = base_output + (self.weight_out * gate * lora_outputs).sum(dim=0)
return output
class FluxLoraPatcher(torch.nn.Module):
def __init__(self, lora_patterns=None):
super().__init__()
if lora_patterns is None:
lora_patterns = self.default_lora_patterns()
model_dict = {}
for lora_pattern in lora_patterns:
name, dim = lora_pattern["name"], lora_pattern["dim"]
model_dict[name.replace(".", "___")] = LoraMerger(dim)
self.model_dict = torch.nn.ModuleDict(model_dict)
def default_lora_patterns(self):
lora_patterns = []
lora_dict = {
"attn.a_to_qkv": 9216, "attn.a_to_out": 3072, "ff_a.0": 12288, "ff_a.2": 3072, "norm1_a.linear": 18432,
"attn.b_to_qkv": 9216, "attn.b_to_out": 3072, "ff_b.0": 12288, "ff_b.2": 3072, "norm1_b.linear": 18432,
}
for i in range(19):
for suffix in lora_dict:
lora_patterns.append({
"name": f"blocks.{i}.{suffix}",
"dim": lora_dict[suffix]
})
lora_dict = {"to_qkv_mlp": 21504, "proj_out": 3072, "norm.linear": 9216}
for i in range(38):
for suffix in lora_dict:
lora_patterns.append({
"name": f"single_blocks.{i}.{suffix}",
"dim": lora_dict[suffix]
})
return lora_patterns
def forward(self, base_output, lora_outputs, name):
return self.model_dict[name.replace(".", "___")](base_output, lora_outputs)
@staticmethod
def state_dict_converter():
return FluxLoraPatcherStateDictConverter()
class FluxLoraPatcherStateDictConverter:
def __init__(self):
pass
def from_civitai(self, state_dict):
return state_dict