[docs] LoRA metadata (#11848)

* draft

* hub image

* update

* fix

Author: stevhliu

docs/source/en/using-diffusers/other-formats.md

@@ -70,41 +70,32 @@ pipeline = StableDiffusionPipeline.from_single_file(
 </hfoption>
 </hfoptions>
 
-#### LoRA files
+#### LoRAs
 
-[LoRA](https://hf.co/docs/peft/conceptual_guides/adapter#low-rank-adaptation-lora) is a lightweight adapter that is fast and easy to train, making them especially popular for generating images in a certain way or style. These adapters are commonly stored in a safetensors file, and are widely popular on model sharing platforms like [civitai](https://civitai.com/).
+[LoRAs](../tutorials/using_peft_for_inference) are lightweight checkpoints fine-tuned to generate images or video in a specific style. If you are using a checkpoint trained with a Diffusers training script, the LoRA configuration is automatically saved as metadata in a safetensors file. When the safetensors file is loaded, the metadata is parsed to correctly configure the LoRA and avoids missing or incorrect LoRA configurations.
 
-LoRAs are loaded into a base model with the [`~loaders.StableDiffusionLoraLoaderMixin.load_lora_weights`] method.
+The easiest way to inspect the metadata, if available, is by clicking on the Safetensors logo next to the weights.
+
+<div class="flex justify-center">
+    <img src="https://huggingface.co/datasets/huggingface/documentation-images/resolve/main/diffusers/safetensors_lora.png"/>
+</div>
+
+For LoRAs that aren't trained with Diffusers, you can still save metadata with the `transformer_lora_adapter_metadata` and `text_encoder_lora_adapter_metadata` arguments in [`~loaders.FluxLoraLoaderMixin.save_lora_weights`] as long as it is a safetensors file.
 
 ```py
-from diffusers import StableDiffusionXLPipeline
 import torch
+from diffusers import FluxPipeline
 
-# base model
-pipeline = StableDiffusionXLPipeline.from_pretrained(
-    "Lykon/dreamshaper-xl-1-0", torch_dtype=torch.float16, variant="fp16"
+pipeline = FluxPipeline.from_pretrained(
+    "black-forest-labs/FLUX.1-dev", torch_dtype=torch.bfloat16
 ).to("cuda")
-
-# download LoRA weights
-!wget https://civitai.com/api/download/models/168776 -O blueprintify.safetensors
-
-# load LoRA weights
-pipeline.load_lora_weights(".", weight_name="blueprintify.safetensors")
-prompt = "bl3uprint, a highly detailed blueprint of the empire state building, explaining how to build all parts, many txt, blueprint grid backdrop"
-negative_prompt = "lowres, cropped, worst quality, low quality, normal quality, artifacts, signature, watermark, username, blurry, more than one bridge, bad architecture"
-
-image = pipeline(
-    prompt=prompt,
-    negative_prompt=negative_prompt,
-    generator=torch.manual_seed(0),
-).images[0]
-image
+pipeline.load_lora_weights("linoyts/yarn_art_Flux_LoRA")
+pipeline.save_lora_weights(
+    transformer_lora_adapter_metadata={"r": 16, "lora_alpha": 16},
+    text_encoder_lora_adapter_metadata={"r": 8, "lora_alpha": 8}
+)
 ```
 
-<div class="flex justify-center">
-    <img src="https://huggingface.co/datasets/huggingface/documentation-images/resolve/main/diffusers/blueprint-lora.png"/>
-</div>
-
 ### ckpt
 
 > [!WARNING]