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docs/source/finetune/train_sd3_lora.md

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+# 训练 Stable Diffusion 3 LoRA
+
+训练脚本只需要一个文件。你可以使用 [`sd3_medium_incl_clips.safetensors`](https://huggingface.co/stabilityai/stable-diffusion-3-medium/resolve/main/sd3_medium_incl_clips.safetensors)（没有 T5 Encoder）或 [`sd3_medium_incl_clips_t5xxlfp16.safetensors`](https://huggingface.co/stabilityai/stable-diffusion-3-medium/resolve/main/sd3_medium_incl_clips_t5xxlfp16.safetensors)（有 T5 Encoder）。请使用以下代码下载这些文件：
+
+
+```python
+from diffsynth import download_models
+
+download_models(["StableDiffusion3", "StableDiffusion3_without_T5"])
+```
+
+```
+models/stable_diffusion_3/
+├── Put Stable Diffusion 3 checkpoints here.txt
+├── sd3_medium_incl_clips.safetensors
+└── sd3_medium_incl_clips_t5xxlfp16.safetensors
+```
+
+使用下面的命令启动训练任务：
+
+```
+CUDA_VISIBLE_DEVICES="0" python examples/train/stable_diffusion_3/train_sd3_lora.py \
+  --pretrained_path models/stable_diffusion_3/sd3_medium_incl_clips.safetensors \
+  --dataset_path data/dog \
+  --output_path ./models \
+  --max_epochs 1 \
+  --steps_per_epoch 500 \
+  --height 1024 \
+  --width 1024 \
+  --center_crop \
+  --precision "16-mixed" \
+  --learning_rate 1e-4 \
+  --lora_rank 4 \
+  --lora_alpha 4 \
+  --use_gradient_checkpointing
+```
+
+有关参数的更多信息，请使用 `python examples/train/stable_diffusion_3/train_sd3_lora.py -h` 查看详细信息。
+
+训练完成后，使用 `model_manager.load_lora` 加载 LoRA 以进行推理。
+
+```python
+from diffsynth import ModelManager, SD3ImagePipeline
+import torch
+
+model_manager = ModelManager(torch_dtype=torch.float16, device="cuda",
+                             file_path_list=["models/stable_diffusion_3/sd3_medium_incl_clips.safetensors"])
+model_manager.load_lora("models/lightning_logs/version_0/checkpoints/epoch=0-step=500.ckpt", lora_alpha=1.0)
+pipe = SD3ImagePipeline.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", 
+    negative_prompt="bad quality, poor quality, doll, disfigured, jpg, toy, bad anatomy, missing limbs, missing fingers, 3d, cgi, extra tails",
+    cfg_scale=7.5,
+    num_inference_steps=100, width=1024, height=1024,
+)
+image.save("image_with_lora.jpg")
+```