--- icon: material/castle --- # Adapting Stable Diffusion XL Stable Diffusion XL (SDXL) is a very popular text-to-image open source foundation model. This guide will show you how to boost its capabilities with Refiners, using iconic adapters the framework supports out-of-the-box, i.e. without the need for tedious prompt engineering. We'll follow a step by step approach, progressively increasing the number of adapters involved to showcase how simple adapter composition is using Refiners. Our use case will be the generation of an image with "a futuristic castle surrounded by a forest, mountains in the background". ## Prerequisites Make sure Refiners is installed in your local environment - see [Getting started](/getting-started/recommended/) - and you have access to a decent GPU. !!! warning As the examples in this guide's code snippets use CUDA, a minimum of 24GB VRAM is needed. Before diving into the adapters themselves, let's establish a baseline by simply prompting SDXL with Refiners. !!! note "Reminder" A StableDiffusion model is composed of three modules: - An Autoencoder, responsible for embedding images into a latent space; - A UNet, responsible for the diffusion process; - A prompt encoder, such as CLIP, responsible for encoding the user prompt which will guide the diffusion process. As Refiners comes with a new model representation - see [Chain](/concepts/chain/) - , you need to download and convert the weights of each module by calling our conversion scripts directly from your terminal (make sure you're in your local `refiners` directory, with your local environment active): ```bash python scripts/conversion/convert_transformers_clip_text_model.py --from "stabilityai/stable-diffusion-xl-base-1.0" --subfolder2 text_encoder_2 --to DoubleCLIPTextEncoder.safetensors --half python scripts/conversion/convert_diffusers_unet.py --from "stabilityai/stable-diffusion-xl-base-1.0" --to sdxl-unet.safetensors --half python scripts/conversion/convert_diffusers_autoencoder_kl.py --from "madebyollin/sdxl-vae-fp16-fix" --subfolder "" --to sdxl-lda.safetensors --half ``` !!! note This will download the original weights from https://huggingface.co/ which takes some time. If you already have this repo cloned locally, use the `--from /path/to/stabilityai/stable-diffusion-xl-base-1.0` option instead. Now, we can write the Python script responsible for inference. Just create a simple `inference.py` file, and open it in your favorite editor. Start by instantiating a [`StableDiffusion_XL`][refiners.foundationals.latent_diffusion.stable_diffusion_xl.StableDiffusion_XL] model and load it with the converted weights: ```py import torch from refiners.fluxion.utils import manual_seed, no_grad from refiners.foundationals.latent_diffusion.stable_diffusion_xl import StableDiffusion_XL # Load SDXL sdxl = StableDiffusion_XL(device="cuda", dtype=torch.float16) # Using half-precision for memory efficiency sdxl.clip_text_encoder.load_from_safetensors("DoubleCLIPTextEncoder.safetensors") sdxl.unet.load_from_safetensors("sdxl-unet.safetensors") sdxl.lda.load_from_safetensors("sdxl-lda.safetensors") ``` Then, define the inference parameters by setting the appropriate prompt / seed / inference steps: ```py # Hyperparameters prompt = "a futuristic castle surrounded by a forest, mountains in the background" seed = 42 sdxl.set_inference_steps(50, first_step=0) # Enable self-attention guidance to enhance the quality of the generated images sdxl.set_self_attention_guidance(enable=True, scale=0.75) # ... Inference process ``` You can now define and run the proper inference process: ```py with no_grad(): # Disable gradient calculation for memory-efficient inference clip_text_embedding, pooled_text_embedding = sdxl.compute_clip_text_embedding( text=prompt + ", best quality, high quality", negative_text="monochrome, lowres, bad anatomy, worst quality, low quality", ) time_ids = sdxl.default_time_ids manual_seed(seed) # SDXL typically generates 1024x1024, here we use a higher resolution. x = sdxl.init_latents((2048, 2048)).to(sdxl.device, sdxl.dtype) # Diffusion process for step in sdxl.steps: if step % 10 == 0: print(f"Step {step}") x = sdxl( x, step=step, clip_text_embedding=clip_text_embedding, pooled_text_embedding=pooled_text_embedding, time_ids=time_ids, ) predicted_image = sdxl.lda.decode_latents(x) predicted_image.save("vanilla_sdxl.png") ``` ??? example "Expand to see the entire end-to-end code" ```py import torch from refiners.fluxion.utils import manual_seed, no_grad from refiners.foundationals.latent_diffusion.stable_diffusion_xl import StableDiffusion_XL # Load SDXL sdxl = StableDiffusion_XL(device="cuda", dtype=torch.float16) sdxl.clip_text_encoder.load_from_safetensors("DoubleCLIPTextEncoder.safetensors") sdxl.unet.load_from_safetensors("sdxl-unet.safetensors") sdxl.lda.load_from_safetensors("sdxl-lda.safetensors") # Hyperparameters prompt = "a futuristic castle surrounded by a forest, mountains in the background" seed = 42 sdxl.set_inference_steps(50, first_step=0) sdxl.set_self_attention_guidance( enable=True, scale=0.75 ) # Enable self-attention guidance to enhance the quality of the generated images with no_grad(): # Disable gradient calculation for memory-efficient inference clip_text_embedding, pooled_text_embedding = sdxl.compute_clip_text_embedding( text=prompt + ", best quality, high quality", negative_text="monochrome, lowres, bad anatomy, worst quality, low quality", ) time_ids = sdxl.default_time_ids manual_seed(seed=seed) # SDXL typically generates 1024x1024, here we use a higher resolution. x = sdxl.init_latents((2048, 2048)).to(sdxl.device, sdxl.dtype) # Diffusion process for step in sdxl.steps: if step % 10 == 0: print(f"Step {step}") x = sdxl( x, step=step, clip_text_embedding=clip_text_embedding, pooled_text_embedding=pooled_text_embedding, time_ids=time_ids, ) predicted_image = sdxl.lda.decode_latents(x) predicted_image.save("vanilla_sdxl.png") ``` It's time to execute your code. The resulting image should look like this:
Generated image of a castle using default SDXL weights
Generated image of a castle using default SDXL weights.
It is not really what we prompted the model for, unfortunately. To get a more futuristic-looking castle, you can either go for tedious prompt engineering, or use a pretrainered LoRA tailored to our use case, like the [Sci-fi Environments](https://civitai.com/models/105945?modelVersionId=140624) LoRA available on Civitai. We'll now show you how the LoRA option works with Refiners. ## Single LoRA To use the [Sci-fi Environments](https://civitai.com/models/105945?modelVersionId=140624) LoRA, all you have to do is download its weights to disk as a `.safetensors`, and inject them into SDXL using [`SDLoraManager`][refiners.foundationals.latent_diffusion.lora.SDLoraManager] right after instantiating `StableDiffusion_XL`: ```py from refiners.fluxion.utils import load_from_safetensors from refiners.foundationals.latent_diffusion.lora import SDLoraManager # Load LoRA weights from disk and inject them into target manager = SDLoraManager(sdxl) scifi_lora_weights = load_from_safetensors("Sci-fi_Environments_sdxl.safetensors") manager.add_loras("scifi-lora", tensors=scifi_lora_weights) ``` ??? example "Expand to see the entire end-to-end code" ```py import torch from refiners.fluxion.utils import load_from_safetensors, manual_seed, no_grad from refiners.foundationals.latent_diffusion.lora import SDLoraManager from refiners.foundationals.latent_diffusion.stable_diffusion_xl import StableDiffusion_XL # Load SDXL sdxl = StableDiffusion_XL(device="cuda", dtype=torch.float16) sdxl.clip_text_encoder.load_from_safetensors("DoubleCLIPTextEncoder.safetensors") sdxl.unet.load_from_safetensors("sdxl-unet.safetensors") sdxl.lda.load_from_safetensors("sdxl-lda.safetensors") # Load LoRA weights from disk and inject them into target manager = SDLoraManager(sdxl) scifi_lora_weights = load_from_safetensors("Sci-fi_Environments_sdxl.safetensors") manager.add_loras("scifi-lora", tensors=scifi_lora_weights) # Hyperparameters prompt = "a futuristic castle surrounded by a forest, mountains in the background" seed = 42 sdxl.set_inference_steps(50, first_step=0) sdxl.set_self_attention_guidance( enable=True, scale=0.75 ) # Enable self-attention guidance to enhance the quality of the generated images with no_grad(): clip_text_embedding, pooled_text_embedding = sdxl.compute_clip_text_embedding( text=prompt + ", best quality, high quality", negative_text="monochrome, lowres, bad anatomy, worst quality, low quality", ) time_ids = sdxl.default_time_ids manual_seed(seed=seed) # SDXL typically generates 1024x1024, here we use a higher resolution. x = sdxl.init_latents((2048, 2048)).to(sdxl.device, sdxl.dtype) # Diffusion process for step in sdxl.steps: if step % 10 == 0: print(f"Step {step}") x = sdxl( x, step=step, clip_text_embedding=clip_text_embedding, pooled_text_embedding=pooled_text_embedding, time_ids=time_ids, ) predicted_image = sdxl.lda.decode_latents(x) predicted_image.save("scifi_sdxl.png") ``` You should get something like this - pretty neat, isn't it?
Sci-fi castle
Generated image of a castle in sci-fi style.
## Multiple LoRAs Continuing with our futuristic castle example, we might want to turn it, for instance, into a pixel art. Again, we could either try some tedious prompt engineering, or instead use another LoRA found on the web, such as [Pixel Art LoRA](https://civitai.com/models/120096/pixel-art-xl?modelVersionId=135931), found on Civitai. This is dead simple as [`SDLoraManager`][refiners.foundationals.latent_diffusion.lora.SDLoraManager] allows loading multiple LoRAs: ```py # Load LoRAs weights from disk and inject them into target manager = SDLoraManager(sdxl) manager.add_loras("scifi-lora", load_from_safetensors("Sci-fi_Environments_sdxl.safetensors")) manager.add_loras("pixel-art-lora", load_from_safetensors("pixel-art-xl-v1.1.safetensors")) ``` Adapters such as LoRAs also have a [scale][refiners.fluxion.adapters.Lora.scale] (roughly) quantifying the effect of this Adapter. Refiners allows setting different scales for each Adapter, allowing the user to balance the effect of each Adapter: ```py # Load LoRAs weights from disk and inject them into target manager = SDLoraManager(sdxl) manager.add_loras("scifi-lora", load_from_safetensors("Sci-fi_Environments_sdxl.safetensors"), scale=1.0) manager.add_loras("pixel-art-lora", load_from_safetensors("pixel-art-xl-v1.1.safetensors"), scale=1.4) ``` ??? example "Expand to see the entire end-to-end code" ```py import torch from refiners.fluxion.utils import load_from_safetensors, manual_seed, no_grad from refiners.foundationals.latent_diffusion.lora import SDLoraManager from refiners.foundationals.latent_diffusion.stable_diffusion_xl import StableDiffusion_XL # Load SDXL sdxl = StableDiffusion_XL(device="cuda", dtype=torch.float16) sdxl.clip_text_encoder.load_from_safetensors("DoubleCLIPTextEncoder.safetensors") sdxl.unet.load_from_safetensors("sdxl-unet.safetensors") sdxl.lda.load_from_safetensors("sdxl-lda.safetensors") # Load LoRAs weights from disk and inject them into target manager = SDLoraManager(sdxl) scifi_lora_weights = load_from_safetensors("Sci-fi_Environments_sdxl.safetensors") pixel_art_lora_weights = load_from_safetensors("pixel-art-xl-v1.1.safetensors") manager.add_loras("scifi-lora", scifi_lora_weights, scale=1.0) manager.add_loras("pixel-art-lora", pixel_art_lora_weights, scale=1.4) # Hyperparameters prompt = "a futuristic castle surrounded by a forest, mountains in the background" seed = 42 sdxl.set_inference_steps(50, first_step=0) sdxl.set_self_attention_guidance( enable=True, scale=0.75 ) # Enable self-attention guidance to enhance the quality of the generated images with no_grad(): clip_text_embedding, pooled_text_embedding = sdxl.compute_clip_text_embedding( text=prompt + ", best quality, high quality", negative_text="monochrome, lowres, bad anatomy, worst quality, low quality", ) time_ids = sdxl.default_time_ids manual_seed(seed=seed) # SDXL typically generates 1024x1024, here we use a higher resolution. x = sdxl.init_latents((2048, 2048)).to(sdxl.device, sdxl.dtype) # Diffusion process for step in sdxl.steps: if step % 10 == 0: print(f"Step {step}") x = sdxl( x, step=step, clip_text_embedding=clip_text_embedding, pooled_text_embedding=pooled_text_embedding, time_ids=time_ids, ) predicted_image = sdxl.lda.decode_latents(x) predicted_image.save("scifi_pixel_sdxl.png") ``` The results are looking great:
Sci-fi Pixel Art castle
Generated image of a castle in sci-fi, pixel art style.
## Multiple LoRAs + IP-Adapter Refiners really shines when it comes to composing different Adapters to fully exploit the possibilities of foundation models. For instance, IP-Adapter (covered in [a previous blog post](https://blog.finegrain.ai/posts/supercharge-stable-diffusion-ip-adapter/)) is a common choice for practictioners wanting to guide the diffusion process towards a specific prompt image. In our example, consider this image of the [Neuschwanstein Castle](https://en.wikipedia.org/wiki/Neuschwanstein_Castle):
Castle Image
Credits: Bayerische Schlösserverwaltung, Anton Brandl
We would like to guide the diffusion process to align with this image, using IP-Adapter. First, download the image as well as the weights of IP-Adapter by calling the following commands from your terminal (again, make sure in you're in your local `refiners` directory): ```bash curl -O https://refine.rs/guides/adapting_sdxl/german-castle.jpg python scripts/conversion/convert_transformers_clip_image_model.py --from "stabilityai/stable-diffusion-2-1-unclip" --to CLIPImageEncoderH.safetensors --half curl -LO https://huggingface.co/h94/IP-Adapter/resolve/main/sdxl_models/ip-adapter-plus_sdxl_vit-h.bin python scripts/conversion/convert_diffusers_ip_adapter.py --from ip-adapter-plus_sdxl_vit-h.bin --half ``` This will download and convert both IP-Adapter and CLIP Image Encoder pretrained weights. Then, in your Python code, simply instantiate a [`SDXLIPAdapter`][refiners.foundationals.latent_diffusion.stable_diffusion_xl.image_prompt.SDXLIPAdapter] targeting our `sdxl.unet`, and inject it using a simple `.inject()` call: ```py # IP-Adapter ip_adapter = SDXLIPAdapter( target=sdxl.unet, weights=load_from_safetensors("ip-adapter-plus_sdxl_vit-h.safetensors"), scale=1.0, fine_grained=True # Use fine-grained IP-Adapter (i.e IP-Adapter Plus) ) ip_adapter.clip_image_encoder.load_from_safetensors("CLIPImageEncoderH.safetensors") ip_adapter.inject() ``` Then, at runtime, we simply compute the embedding of the image prompt through the `ip_adapter` object, and set its embedding calling `.set_clip_image_embedding()`: ```py from PIL import Image image_prompt = Image.open("german-castle.jpg") with torch.no_grad(): clip_image_embedding = ip_adapter.compute_clip_image_embedding(ip_adapter.preprocess_image(image_prompt)) ip_adapter.set_clip_image_embedding(clip_image_embedding) # And start the diffusion process ``` !!! note Be wary that composing Adapters (especially ones of different natures, such as LoRAs and IP-Adapter) can be tricky, as their respective effects can be adversarial. This is visible in our example below. In the code below, we tuned the LoRAs scales respectively to `1.5` and `1.55`. We invite you to try and test different seeds and scales to find the perfect combination! ??? example "Expand to see the entire end-to-end code" ```py import torch from PIL import Image from refiners.fluxion.utils import load_from_safetensors, manual_seed, no_grad from refiners.foundationals.latent_diffusion.lora import SDLoraManager from refiners.foundationals.latent_diffusion.stable_diffusion_xl import StableDiffusion_XL from refiners.foundationals.latent_diffusion.stable_diffusion_xl.image_prompt import SDXLIPAdapter # Load SDXL sdxl = StableDiffusion_XL(device="cuda", dtype=torch.float16) sdxl.clip_text_encoder.load_from_safetensors("DoubleCLIPTextEncoder.safetensors") sdxl.unet.load_from_safetensors("sdxl-unet.safetensors") sdxl.lda.load_from_safetensors("sdxl-lda.safetensors") # Load LoRAs weights from disk and inject them into target manager = SDLoraManager(sdxl) scifi_lora_weights = load_from_safetensors("Sci-fi_Environments_sdxl.safetensors") pixel_art_lora_weights = load_from_safetensors("pixel-art-xl-v1.1.safetensors") manager.add_loras("scifi-lora", scifi_lora_weights, scale=1.5) manager.add_loras("pixel-art-lora", pixel_art_lora_weights, scale=1.55) # Load IP-Adapter ip_adapter = SDXLIPAdapter( target=sdxl.unet, weights=load_from_safetensors("ip-adapter-plus_sdxl_vit-h.safetensors"), scale=1.0, fine_grained=True, # Use fine-grained IP-Adapter (IP-Adapter Plus) ) ip_adapter.clip_image_encoder.load_from_safetensors("CLIPImageEncoderH.safetensors") ip_adapter.inject() # Hyperparameters prompt = "a futuristic castle surrounded by a forest, mountains in the background" image_prompt = Image.open("german-castle.jpg") seed = 42 sdxl.set_inference_steps(50, first_step=0) sdxl.set_self_attention_guidance( enable=True, scale=0.75 ) # Enable self-attention guidance to enhance the quality of the generated images with no_grad(): clip_text_embedding, pooled_text_embedding = sdxl.compute_clip_text_embedding( text=prompt + ", best quality, high quality", negative_text="monochrome, lowres, bad anatomy, worst quality, low quality", ) time_ids = sdxl.default_time_ids clip_image_embedding = ip_adapter.compute_clip_image_embedding(ip_adapter.preprocess_image(image_prompt)) ip_adapter.set_clip_image_embedding(clip_image_embedding) manual_seed(seed=seed) x = sdxl.init_latents((1024, 1024)).to(sdxl.device, sdxl.dtype) # Diffusion process for step in sdxl.steps: if step % 10 == 0: print(f"Step {step}") x = sdxl( x, step=step, clip_text_embedding=clip_text_embedding, pooled_text_embedding=pooled_text_embedding, time_ids=time_ids, ) predicted_image = sdxl.lda.decode_latents(x) predicted_image.save("scifi_pixel_IP_sdxl.png") ``` The result looks convincing: we do get a *pixel-art, futuristic-looking Neuschwanstein castle*!
Generated image in sci-fi, pixel art style, using IP-Adapter.
Generated image in sci-fi, pixel art style, using IP-Adapter.
## Everything else + T2I-Adapter T2I-Adapters[^1] are a powerful class of Adapters aiming at controlling the Text-to-Image (T2I) diffusion process with external control signals, such as canny edges or pose estimations inputs. In this section, we will compose our previous example with the [Depth-Zoe Adapter](https://huggingface.co/TencentARC/t2i-adapter-depth-zoe-sdxl-1.0), providing a depth condition to the diffusion process using the following depth map as input signal:
Input depth map of the initial castle image
Input depth map of the initial castle image.
First, download the image as well as the weights of T2I-Depth-Zoe-Adapter by calling the following commands: ```bash curl -O https://refine.rs/guides/adapting_sdxl/zoe-depth-map-german-castle.png python scripts/conversion/convert_diffusers_t2i_adapter.py --from "TencentARC/t2i-adapter-depth-zoe-sdxl-1.0" --to t2i_depth_zoe_xl.safetensors --half ``` Then, just inject it as usual: ```py # Load T2I-Adapter t2i_adapter = SDXLT2IAdapter( target=sdxl.unet, name="zoe-depth", weights=load_from_safetensors("t2i_depth_zoe_xl.safetensors"), scale=0.72, ).inject() ``` Finally, at runtime, compute the embedding of the input condition through the `t2i_adapter` object, and set its embedding calling `.set_condition_features()`: ```py from refiners.fluxion.utils import image_to_tensor, interpolate image_depth_condition = Image.open("zoe-depth-map-german-castle.png") with torch.no_grad(): condition = image_to_tensor(image_depth_condition.convert("RGB"), device=sdxl.device, dtype=sdxl.dtype) # Spatial dimensions should be divisible by default downscale factor (=16 for T2IAdapter ConditionEncoder) condition = interpolate(condition, torch.Size((1024, 1024))) t2i_adapter.set_condition_features(features=t2i_adapter.compute_condition_features(condition)) ``` ??? example "Expand to see the entire end-to-end code" ```py import torch from PIL import Image from refiners.fluxion.utils import load_from_safetensors, manual_seed, no_grad, image_to_tensor from refiners.foundationals.latent_diffusion.lora import SDLoraManager from refiners.foundationals.latent_diffusion.stable_diffusion_xl import StableDiffusion_XL, SDXLT2IAdapter from refiners.foundationals.latent_diffusion.stable_diffusion_xl.image_prompt import SDXLIPAdapter # Load SDXL sdxl = StableDiffusion_XL(device="cuda", dtype=torch.float16) sdxl.clip_text_encoder.load_from_safetensors("DoubleCLIPTextEncoder.safetensors") sdxl.unet.load_from_safetensors("sdxl-unet.safetensors") sdxl.lda.load_from_safetensors("sdxl-lda.safetensors") # Load LoRAs weights from disk and inject them into target manager = SDLoraManager(sdxl) scifi_lora_weights = load_from_safetensors("Sci-fi_Environments_sdxl.safetensors") pixel_art_lora_weights = load_from_safetensors("pixel-art-xl-v1.1.safetensors") manager.add_loras("scifi-lora", scifi_lora_weights, scale=1.5) manager.add_loras("pixel-art-lora", pixel_art_lora_weights, scale=1.55) # Load IP-Adapter ip_adapter = SDXLIPAdapter( target=sdxl.unet, weights=load_from_safetensors("ip-adapter-plus_sdxl_vit-h.safetensors"), scale=1.0, fine_grained=True, # Use fine-grained IP-Adapter (IP-Adapter Plus) ) ip_adapter.clip_image_encoder.load_from_safetensors("CLIPImageEncoderH.safetensors") ip_adapter.inject() # Load T2I-Adapter t2i_adapter = SDXLT2IAdapter( target=sdxl.unet, name="zoe-depth", weights=load_from_safetensors("t2i_depth_zoe_xl.safetensors"), scale=0.72, ).inject() # Hyperparameters prompt = "a futuristic castle surrounded by a forest, mountains in the background" image_prompt = Image.open("german-castle.jpg") image_depth_condition = Image.open("zoe-depth-map-german-castle.png") seed = 42 sdxl.set_inference_steps(50, first_step=0) sdxl.set_self_attention_guidance( enable=True, scale=0.75 ) # Enable self-attention guidance to enhance the quality of the generated images with no_grad(): clip_text_embedding, pooled_text_embedding = sdxl.compute_clip_text_embedding( text=prompt + ", best quality, high quality", negative_text="monochrome, lowres, bad anatomy, worst quality, low quality", ) time_ids = sdxl.default_time_ids clip_image_embedding = ip_adapter.compute_clip_image_embedding(ip_adapter.preprocess_image(image_prompt)) ip_adapter.set_clip_image_embedding(clip_image_embedding) # Spatial dimensions should be divisible by default downscale factor (=16 for T2IAdapter ConditionEncoder) condition = image_to_tensor(image_depth_condition.convert("RGB").resize((1024, 1024)), device=sdxl.device, dtype=sdxl.dtype) t2i_adapter.set_condition_features(features=t2i_adapter.compute_condition_features(condition)) manual_seed(seed=seed) x = sdxl.init_latents((1024, 1024)).to(sdxl.device, sdxl.dtype) # Diffusion process for step in sdxl.steps: if step % 10 == 0: print(f"Step {step}") x = sdxl( x, step=step, clip_text_embedding=clip_text_embedding, pooled_text_embedding=pooled_text_embedding, time_ids=time_ids, ) predicted_image = sdxl.lda.decode_latents(x) predicted_image.save("scifi_pixel_IP_T2I_sdxl.png") ``` The results look convincing: the depth and proportions of the initial castle are more faithful, while preserving our *futuristic, pixel-art style*!
Generated image in sci-fi, pixel art style, using IP and T2I Adapters
Generated image in sci-fi, pixel art style, using IP and T2I Adapters.
## Wrap up As you can see in this guide, composing Adapters on top of foundation models is pretty seamless in Refiners, allowing practitioners to quickly test out different combinations of Adapters for their needs. We encourage you to try out different ones, and even train some yourselves! [^1]: Mou, C., Wang, X., Xie, L., Zhang, J., Qi, Z., Shan, Y., & Qie, X. (2023). T2i-adapter: Learning adapters to dig out more controllable ability for text-to-image diffusion models.