import spaces import gradio as gr from sd3_pipeline import StableDiffusion3Pipeline import torch import random import numpy as np import os import gc from diffusers import AutoencoderKLWan from wan_pipeline import WanPipeline from diffusers.schedulers.scheduling_unipc_multistep import UniPCMultistepScheduler from PIL import Image from diffusers.utils import export_to_video from huggingface_hub import login # Authenticate with HF login(token=os.getenv('HF_TOKEN')) def set_seed(seed): random.seed(seed) os.environ['PYTHONHASHSEED'] = str(seed) np.random.seed(seed) torch.manual_seed(seed) torch.cuda.manual_seed(seed) model_paths = { "sd3": "stabilityai/stable-diffusion-3-medium-diffusers", "sd3.5": "stabilityai/stable-diffusion-3.5-large", # "wan-t2v": "Wan-AI/Wan2.1-T2V-1.3B-Diffusers" } current_model = None OUTPUT_DIR = "generated_videos" os.makedirs(OUTPUT_DIR, exist_ok=True) def load_model(model_name): global current_model if current_model is not None: del current_model torch.cuda.empty_cache() gc.collect() if "wan-t2v" in model_name: vae = AutoencoderKLWan.from_pretrained(model_paths[model_name], subfolder="vae", torch_dtype=torch.bfloat16) scheduler = UniPCMultistepScheduler(prediction_type='flow_prediction', use_flow_sigmas=True, num_train_timesteps=1000, flow_shift=8.0) current_model = WanPipeline.from_pretrained(model_paths[model_name], vae=vae, torch_dtype=torch.float16).to("cuda") current_model.scheduler = scheduler else: current_model = StableDiffusion3Pipeline.from_pretrained(model_paths[model_name], torch_dtype=torch.bfloat16).to("cuda") return current_model.to("cuda") @spaces.GPU(duration=120) def generate_content(prompt, model_name, guidance_scale=7.5, num_inference_steps=50, use_cfg_zero_star=True, use_zero_init=True, zero_steps=0, seed=None, compare_mode=False): model = load_model(model_name) if seed is None: seed = random.randint(0, 2**32 - 1) set_seed(seed) is_video_model = "wan-t2v" in model_name print('prompt: ',prompt) if is_video_model: negative_prompt = "Bright tones, overexposed, static, blurred details, subtitles, style, works, paintings, images, static, overall gray, worst quality, low quality, JPEG compression residue, ugly, incomplete, extra fingers, poorly drawn hands, poorly drawn faces, deformed, disfigured, misshapen limbs, fused fingers, still picture, messy background, three legs, many people in the background, walking backwards" video1_frames = model( prompt=prompt, negative_prompt=negative_prompt, height=480, width=832, num_frames=81, num_inference_steps=num_inference_steps, guidance_scale=guidance_scale, use_cfg_zero_star=True, use_zero_init=True, zero_steps=zero_steps ).frames[0] video1_path = os.path.join(OUTPUT_DIR, f"{seed}_CFG-Zero-Star.mp4") export_to_video(video1_frames, video1_path, fps=16) return None, None, video1_path, seed if compare_mode: set_seed(seed) image1 = model( prompt, guidance_scale=guidance_scale, num_inference_steps=num_inference_steps, use_cfg_zero_star=True, use_zero_init=use_zero_init, zero_steps=zero_steps ).images[0] set_seed(seed) image2 = model( prompt, guidance_scale=guidance_scale, num_inference_steps=num_inference_steps, use_cfg_zero_star=False, use_zero_init=use_zero_init, zero_steps=zero_steps ).images[0] return image1, image2, seed else: image = model( prompt, guidance_scale=guidance_scale, num_inference_steps=num_inference_steps, use_cfg_zero_star=use_cfg_zero_star, use_zero_init=use_zero_init, zero_steps=zero_steps ).images[0] if use_cfg_zero_star: return image, None, seed else: return None, image, seed # Gradio UI with left-right layout with gr.Blocks() as demo: gr.HTML("""
CFG-Zero*: Improved Classifier-Free Guidance for Flow Matching Models
Code | Paper
""") with gr.Row(): with gr.Column(scale=1): prompt = gr.Textbox(value="A spooky haunted mansion on a hill silhouetted by a full moon.", label="Enter your prompt") model_choice = gr.Dropdown(choices=list(model_paths.keys()), label="Choose Model") guidance_scale = gr.Slider(1, 20, value=4.0, step=0.5, label="Guidance Scale") inference_steps = gr.Slider(10, 100, value=50, step=5, label="Inference Steps") use_opt_scale = gr.Checkbox(value=True, label="Use Optimized-Scale") use_zero_init = gr.Checkbox(value=True, label="Use Zero Init") zero_steps = gr.Slider(0, 20, value=1, step=1, label="Zero out steps") seed = gr.Number(value=42, label="Seed (Leave blank for random)") compare_mode = gr.Checkbox(value=True, label="Compare Mode") generate_btn = gr.Button("Generate") with gr.Column(scale=2): out1 = gr.Image(type="pil", label="CFG-Zero* Image") out2 = gr.Image(type="pil", label="CFG Image") #video = gr.Video(label="Video") used_seed = gr.Textbox(label="Used Seed") def update_params(model_name): print('model_name: ',model_name) if model_name == "wan-t2v": return ( gr.update(value=5), gr.update(value=50), gr.update(value=True), gr.update(value=True), gr.update(value=1) ) else: return ( gr.update(value=4.0), gr.update(value=50), gr.update(value=True), gr.update(value=True), gr.update(value=1) ) model_choice.change( fn=update_params, inputs=[model_choice], outputs=[guidance_scale, inference_steps, use_opt_scale, use_zero_init, zero_steps] ) generate_btn.click( fn=generate_content, inputs=[ prompt, model_choice, guidance_scale, inference_steps, use_opt_scale, use_zero_init, zero_steps, seed, compare_mode ], outputs=[out1, out2, used_seed] ) demo.launch(ssr_mode=False)