# 训练 FLUX LoRA

以下文件将会被用于构建 FLUX 模型。 你可以从[huggingface](https://huggingface.co/black-forest-labs/FLUX.1-dev)或[modelscope](https://www.modelscope.cn/models/ai-modelscope/flux.1-dev)下载，也可以使用以下代码下载这些文件:

```python
from diffsynth import download_models

download_models(["FLUX.1-dev"])
```

```
models/FLUX/
└── FLUX.1-dev
    ├── ae.safetensors
    ├── flux1-dev.safetensors
    ├── text_encoder
    │   └── model.safetensors
    └── text_encoder_2
        ├── config.json
        ├── model-00001-of-00002.safetensors
        ├── model-00002-of-00002.safetensors
        └── model.safetensors.index.json
```

使用以下命令启动训练任务（需要39G显存）：

```
CUDA_VISIBLE_DEVICES="0" python examples/train/flux/train_flux_lora.py \
  --pretrained_text_encoder_path models/FLUX/FLUX.1-dev/text_encoder/model.safetensors \
  --pretrained_text_encoder_2_path models/FLUX/FLUX.1-dev/text_encoder_2 \
  --pretrained_dit_path models/FLUX/FLUX.1-dev/flux1-dev.safetensors \
  --pretrained_vae_path models/FLUX/FLUX.1-dev/ae.safetensors \
  --dataset_path data/dog \
  --output_path ./models \
  --max_epochs 1 \
  --steps_per_epoch 100 \
  --height 1024 \
  --width 1024 \
  --center_crop \
  --precision "bf16" \
  --learning_rate 1e-4 \
  --lora_rank 16 \
  --lora_alpha 16 \
  --use_gradient_checkpointing \
  --align_to_opensource_format
```

通过添加参数 `--quantize "float8_e4m3fn"`，你可以节省大约 10G 的显存。

**`--align_to_opensource_format` 表示此脚本将以开源格式导出 LoRA 权重。此格式可以在 DiffSynth-Studio 和其他代码库中加载。**

有关参数的更多信息，请使用 `python examples/train/flux/train_flux_lora.py -h` 查看详细信息。

训练完成后，使用 model_manager.load_lora 来加载 LoRA 以进行推理。


```python
from diffsynth import ModelManager, FluxImagePipeline
import torch

model_manager = ModelManager(torch_dtype=torch.bfloat16, device="cuda",
                             file_path_list=[
                                 "models/FLUX/FLUX.1-dev/text_encoder/model.safetensors",
                                 "models/FLUX/FLUX.1-dev/text_encoder_2",
                                 "models/FLUX/FLUX.1-dev/ae.safetensors",
                                 "models/FLUX/FLUX.1-dev/flux1-dev.safetensors"
                             ])
model_manager.load_lora("models/lightning_logs/version_0/checkpoints/epoch=0-step=500.ckpt", lora_alpha=1.0)
pipe = FluxImagePipeline.from_model_manager(model_manager)

torch.manual_seed(0)
image = pipe(
    prompt="a dog is jumping, flowers around the dog, the background is mountains and clouds",
    num_inference_steps=30, embedded_guidance=3.5
)
image.save("image_with_lora.jpg")
```
