app.py

import torch
import gradio as gr
import numpy as np
from diffusers import FluxKontextPipeline
from gfpgan import GFPGANer
from PIL import Image

# Device setup
device = torch.device("cuda" if torch.cuda.is_available() else "cpu")

# Load FLUX in-context editing pipeline
pipe = FluxKontextPipeline.from_pretrained(
    "black-forest-labs/FLUX.1-Kontext-dev",
    torch_dtype=torch.bfloat16 if device.type=="cuda" else torch.float32
).to(device)

# Load face enhancement model
gfpgan = GFPGANer(
    model_path="https://github.com/TencentARC/GFPGAN/releases/download/v1.3.4/GFPGANv1.3.pth",
    upscale=1,
    arch="clean",
    channel_multiplier=2,
    bg_upsampler=None,
    device=device.type
)

def enhance_face(input_img: Image.Image) -> Image.Image:
    img_np = np.array(input_img)
    _, _, output = gfpgan.enhance(img_np, has_aligned=False, only_center_face=False, paste_back=True)
    return Image.fromarray(output)

def infer(input_image, prompt, beautify, seed, randomize, steps, guidance_scale):
    # Set random seed
    generator = torch.Generator(device=device).manual_seed(seed if not randomize else torch.randint(0, 2**32-1, ()).item())

    # In-context editing
    out = pipe(
        image=input_image.convert("RGB"),
        prompt=prompt,
        num_inference_steps=steps,
        guidance_scale=guidance_scale,
        generator=generator
    ).images[0]

    # Apply face enhancement if selected
    if beautify:
        out = enhance_face(out)

    return out

# UI setup
with gr.Blocks() as demo:
    gr.Markdown("# FLUX Kontekt Editor + Beautify")
    with gr.Row():
        input_image = gr.Image(label="Upload Image", type="pil")
        result = gr.Image(label="Edited Output")
    prompt = gr.Textbox(label="Edit Prompt", placeholder="e.g., 'change background to beach'")
    beautify = gr.Checkbox(label="Beautify Face", value=True)
    seed = gr.Slider(0, 2**32-1, value=0, step=1, label="Seed")
    randomize = gr.Checkbox(label="Randomize Seed", value=True)
    steps = gr.Slider(1, 30, value=28, label="Steps")
    guidance = gr.Slider(1.0, 10.0, value=2.5, step=0.1, label="Guidance Scale")
    run = gr.Button("Run")

    run.click(
        fn=infer,
        inputs=[input_image, prompt, beautify, seed, randomize, steps, guidance],
        outputs=result
    )

demo.launch()