import math import argparse import os import torch from safetensors.torch import load_file, save_file import library.model_util as model_util import lora def load_state_dict(file_name, dtype): if os.path.splitext(file_name)[1] == ".safetensors": sd = load_file(file_name) else: sd = torch.load(file_name, map_location="cpu") for key in list(sd.keys()): if type(sd[key]) == torch.Tensor: sd[key] = sd[key].to(dtype) return sd def save_to_file(file_name, model, state_dict, dtype): if dtype is not None: for key in list(state_dict.keys()): if type(state_dict[key]) == torch.Tensor: state_dict[key] = state_dict[key].to(dtype) if os.path.splitext(file_name)[1] == ".safetensors": save_file(model, file_name) else: torch.save(model, file_name) def merge_to_sd_model(text_encoder, unet, models, ratios, merge_dtype): text_encoder.to(merge_dtype) unet.to(merge_dtype) # create module map name_to_module = {} for i, root_module in enumerate([text_encoder, unet]): if i == 0: prefix = lora.LoRANetwork.LORA_PREFIX_TEXT_ENCODER target_replace_modules = lora.LoRANetwork.TEXT_ENCODER_TARGET_REPLACE_MODULE else: prefix = lora.LoRANetwork.LORA_PREFIX_UNET target_replace_modules = ( lora.LoRANetwork.UNET_TARGET_REPLACE_MODULE + lora.LoRANetwork.UNET_TARGET_REPLACE_MODULE_CONV2D_3X3 ) for name, module in root_module.named_modules(): if module.__class__.__name__ in target_replace_modules: for child_name, child_module in module.named_modules(): if child_module.__class__.__name__ == "Linear" or child_module.__class__.__name__ == "Conv2d": lora_name = prefix + "." + name + "." + child_name lora_name = lora_name.replace(".", "_") name_to_module[lora_name] = child_module for model, ratio in zip(models, ratios): print(f"loading: {model}") lora_sd = load_state_dict(model, merge_dtype) print(f"merging...") for key in lora_sd.keys(): if "lora_down" in key: up_key = key.replace("lora_down", "lora_up") alpha_key = key[: key.index("lora_down")] + "alpha" # find original module for this lora module_name = ".".join(key.split(".")[:-2]) # remove trailing ".lora_down.weight" if module_name not in name_to_module: print(f"no module found for LoRA weight: {key}") continue module = name_to_module[module_name] # print(f"apply {key} to {module}") down_weight = lora_sd[key] up_weight = lora_sd[up_key] dim = down_weight.size()[0] alpha = lora_sd.get(alpha_key, dim) scale = alpha / dim # W <- W + U * D weight = module.weight # print(module_name, down_weight.size(), up_weight.size()) if len(weight.size()) == 2: # linear weight = weight + ratio * (up_weight @ down_weight) * scale elif down_weight.size()[2:4] == (1, 1): # conv2d 1x1 weight = ( weight + ratio * (up_weight.squeeze(3).squeeze(2) @ down_weight.squeeze(3).squeeze(2)).unsqueeze(2).unsqueeze(3) * scale ) else: # conv2d 3x3 conved = torch.nn.functional.conv2d(down_weight.permute(1, 0, 2, 3), up_weight).permute(1, 0, 2, 3) # print(conved.size(), weight.size(), module.stride, module.padding) weight = weight + ratio * conved * scale module.weight = torch.nn.Parameter(weight) def merge_lora_models(models, ratios, merge_dtype): base_alphas = {} # alpha for merged model base_dims = {} merged_sd = {} for model, ratio in zip(models, ratios): print(f"loading: {model}") lora_sd = load_state_dict(model, merge_dtype) # get alpha and dim alphas = {} # alpha for current model dims = {} # dims for current model for key in lora_sd.keys(): if "alpha" in key: lora_module_name = key[: key.rfind(".alpha")] alpha = float(lora_sd[key].detach().numpy()) alphas[lora_module_name] = alpha if lora_module_name not in base_alphas: base_alphas[lora_module_name] = alpha elif "lora_down" in key: lora_module_name = key[: key.rfind(".lora_down")] dim = lora_sd[key].size()[0] dims[lora_module_name] = dim if lora_module_name not in base_dims: base_dims[lora_module_name] = dim for lora_module_name in dims.keys(): if lora_module_name not in alphas: alpha = dims[lora_module_name] alphas[lora_module_name] = alpha if lora_module_name not in base_alphas: base_alphas[lora_module_name] = alpha print(f"dim: {list(set(dims.values()))}, alpha: {list(set(alphas.values()))}") # merge print(f"merging...") for key in lora_sd.keys(): if "alpha" in key: continue lora_module_name = key[: key.rfind(".lora_")] base_alpha = base_alphas[lora_module_name] alpha = alphas[lora_module_name] scale = math.sqrt(alpha / base_alpha) * ratio if key in merged_sd: assert ( merged_sd[key].size() == lora_sd[key].size() ), f"weights shape mismatch merging v1 and v2, different dims? / 重みのサイズが合いません。v1とv2、または次元数の異なるモデルはマージできません" merged_sd[key] = merged_sd[key] + lora_sd[key] * scale else: merged_sd[key] = lora_sd[key] * scale # set alpha to sd for lora_module_name, alpha in base_alphas.items(): key = lora_module_name + ".alpha" merged_sd[key] = torch.tensor(alpha) print("merged model") print(f"dim: {list(set(base_dims.values()))}, alpha: {list(set(base_alphas.values()))}") return merged_sd def merge(args): assert len(args.models) == len(args.ratios), f"number of models must be equal to number of ratios / モデルの数と重みの数は合わせてください" def str_to_dtype(p): if p == "float": return torch.float if p == "fp16": return torch.float16 if p == "bf16": return torch.bfloat16 return None merge_dtype = str_to_dtype(args.precision) save_dtype = str_to_dtype(args.save_precision) if save_dtype is None: save_dtype = merge_dtype if args.sd_model is not None: print(f"loading SD model: {args.sd_model}") text_encoder, vae, unet = model_util.load_models_from_stable_diffusion_checkpoint(args.v2, args.sd_model) merge_to_sd_model(text_encoder, unet, args.models, args.ratios, merge_dtype) print(f"saving SD model to: {args.save_to}") model_util.save_stable_diffusion_checkpoint(args.v2, args.save_to, text_encoder, unet, args.sd_model, 0, 0, save_dtype, vae) else: state_dict = merge_lora_models(args.models, args.ratios, merge_dtype) print(f"saving model to: {args.save_to}") save_to_file(args.save_to, state_dict, state_dict, save_dtype) def setup_parser() -> argparse.ArgumentParser: parser = argparse.ArgumentParser() parser.add_argument("--v2", action="store_true", help="load Stable Diffusion v2.x model / Stable Diffusion 2.xのモデルを読み込む") parser.add_argument( "--save_precision", type=str, default=None, choices=[None, "float", "fp16", "bf16"], help="precision in saving, same to merging if omitted / 保存時に精度を変更して保存する、省略時はマージ時の精度と同じ", ) parser.add_argument( "--precision", type=str, default="float", choices=["float", "fp16", "bf16"], help="precision in merging (float is recommended) / マージの計算時の精度（floatを推奨）", ) parser.add_argument( "--sd_model", type=str, default=None, help="Stable Diffusion model to load: ckpt or safetensors file, merge LoRA models if omitted / 読み込むモデル、ckptまたはsafetensors。省略時はLoRAモデル同士をマージする", ) parser.add_argument( "--save_to", type=str, default=None, help="destination file name: ckpt or safetensors file / 保存先のファイル名、ckptまたはsafetensors" ) parser.add_argument( "--models", type=str, nargs="*", help="LoRA models to merge: ckpt or safetensors file / マージするLoRAモデル、ckptまたはsafetensors" ) parser.add_argument("--ratios", type=float, nargs="*", help="ratios for each model / それぞれのLoRAモデルの比率") return parser if __name__ == "__main__": parser = setup_parser() args = parser.parse_args() merge(args)