Diffusers documentation
ControlNet
ControlNet
ControlNet steers a pretrained diffusion model with a structural control image (edges, depth, or pose) while you keep a text prompt. It freezes the base model and adds a parallel network whose residuals guide the denoiser, so you get layout control without fine-tuning.
Load a ControlNet for the control you need (for example canny), then pass it as controlnet= to from_pretrained(). Use controlnet_conditioning_scale to set how strongly the control steers generation.
ControlNets are available to many models such as Flux, Hunyuan-DiT, Stable Diffusion 3, and more. The examples in this guide use Flux and Stable Diffusion XL. For T2I-Adapter on older Stable Diffusion–family checkpoints, see Legacy adapters. Prefer ControlNet for new controllable-generation work.
The tabs below show ControlNet for text-to-image, image-to-image, and inpainting.
Generate a canny image with opencv-python.
import cv2
import numpy as np
from PIL import Image
from diffusers.utils import load_image
original_image = load_image(
"https://huggingface.co/datasets/huggingface/documentation-images/resolve/main/diffusers/non-enhanced-prompt.png"
)
image = np.array(original_image)
low_threshold = 100
high_threshold = 200
image = cv2.Canny(image, low_threshold, high_threshold)
image = image[:, :, None]
image = np.concatenate([image, image, image], axis=2)
canny_image = Image.fromarray(image)Pass the canny image to the pipeline. Use the controlnet_conditioning_scale parameter to determine how much weight to assign to the control.
import torch
from diffusers.utils import load_image
from diffusers import FluxControlNetPipeline, FluxControlNetModel
controlnet = FluxControlNetModel.from_pretrained(
"InstantX/FLUX.1-dev-Controlnet-Canny", dtype=torch.bfloat16
)
pipeline = FluxControlNetPipeline.from_pretrained(
"black-forest-labs/FLUX.1-dev", controlnet=controlnet, dtype=torch.bfloat16
).to("cuda") # or "mps", "xpu", "cpu"
prompt = """
A photorealistic overhead image of a cat reclining sideways in a flamingo pool floatie holding a margarita.
The cat is floating leisurely in the pool and completely relaxed and happy.
"""
pipeline(
prompt,
control_image=canny_image,
controlnet_conditioning_scale=0.5,
num_inference_steps=50,
guidance_scale=3.5,
).images[0]
Multi-ControlNet
Compose several ControlNets (for example canny + depth) by passing them as a list. Mask overlapping regions when you can, and tune each controlnet_conditioning_scale. Build canny_image with OpenCV Canny (as in text-to-image) and depth_image with DPT (as in image-to-image). Resize every control image to the pipeline size before you call the pipeline.
import cv2
import torch
import numpy as np
from PIL import Image
from transformers import DPTImageProcessor, DPTForDepthEstimation
from diffusers import StableDiffusionXLControlNetPipeline, ControlNetModel, AutoencoderKL
from diffusers.utils import load_image
original_image = load_image(
"https://huggingface.co/datasets/huggingface/documentation-images/resolve/main/diffusers/non-enhanced-prompt.png"
)
image = np.array(original_image)
canny_image = Image.fromarray(
np.concatenate([cv2.Canny(image, 100, 200)[:, :, None]] * 3, axis=2)
)
device = "cuda" # or "mps", "xpu", "cpu"
depth_estimator = DPTForDepthEstimation.from_pretrained("Intel/dpt-hybrid-midas").to(device)
feature_extractor = DPTImageProcessor.from_pretrained("Intel/dpt-hybrid-midas")
def get_depth_map(image):
image = feature_extractor(images=image, return_tensors="pt").pixel_values.to(device)
with torch.no_grad(), torch.autocast(device):
depth_map = depth_estimator(image).predicted_depth
depth_map = torch.nn.functional.interpolate(
depth_map.unsqueeze(1),
size=(1024, 1024),
mode="bicubic",
align_corners=False,
)
depth_min = torch.amin(depth_map, dim=[1, 2, 3], keepdim=True)
depth_max = torch.amax(depth_map, dim=[1, 2, 3], keepdim=True)
depth_map = (depth_map - depth_min) / (depth_max - depth_min)
image = torch.cat([depth_map] * 3, dim=1)
image = image.permute(0, 2, 3, 1).cpu().numpy()[0]
image = Image.fromarray((image * 255.0).clip(0, 255).astype(np.uint8))
return image
depth_image = get_depth_map(original_image.resize((1024, 1024)))
controlnets = [
ControlNetModel.from_pretrained(
"diffusers/controlnet-canny-sdxl-1.0", dtype=torch.float16
),
ControlNetModel.from_pretrained(
"diffusers/controlnet-depth-sdxl-1.0-small", dtype=torch.float16
),
]
vae = AutoencoderKL.from_pretrained("madebyollin/sdxl-vae-fp16-fix", dtype=torch.float16)
pipeline = StableDiffusionXLControlNetPipeline.from_pretrained(
"stabilityai/stable-diffusion-xl-base-1.0", controlnet=controlnets, vae=vae, dtype=torch.float16
).to(device)
prompt = """
a relaxed rabbit sitting on a striped towel next to a pool with a tropical drink nearby,
bright sunny day, vacation scene, 35mm photograph, film, professional, 4k, highly detailed
"""
negative_prompt = "lowres, bad anatomy, worst quality, low quality, deformed, ugly"
images = [canny_image.resize((1024, 1024)), depth_image.resize((1024, 1024))]
pipeline(
prompt,
negative_prompt=negative_prompt,
image=images,
num_inference_steps=100,
controlnet_conditioning_scale=[0.5, 0.5],
).images[0]
Guess mode
Guess mode generates an image from a control alone when you don’t have (or don’t want) a text prompt. It scales ControlNet residuals by block depth, from about 0.1 in early down blocks up to 1.0 at the mid block. That keeps early layers from over-constraining while deeper blocks still carry the structure.
import torch
from diffusers.utils import load_image
from diffusers import StableDiffusionXLControlNetPipeline, ControlNetModel
controlnet = ControlNetModel.from_pretrained(
"diffusers/controlnet-canny-sdxl-1.0", dtype=torch.float16
)
pipeline = StableDiffusionXLControlNetPipeline.from_pretrained(
"stabilityai/stable-diffusion-xl-base-1.0",
controlnet=controlnet,
dtype=torch.float16
).to("cuda") # or "mps", "xpu", "cpu"
canny_image = load_image("https://huggingface.co/datasets/huggingface/documentation-images/resolve/main/diffusers/canny-cat.png")
pipeline(
"",
image=canny_image,
guess_mode=True
).images[0]