app.py

import fitz  # PyMuPDF
import gradio as gr
from PIL import Image, ImageEnhance, ImageFilter
import io

# Step 1: Convert PDF to high-quality image
def pdf_to_image(pdf_file, dpi=600):
    try:
        print(f"Opening PDF: {pdf_file.name}")
        pdf_document = fitz.open(pdf_file.name)
        page = pdf_document.load_page(0)  # Load the first page

        # Render the page at high DPI
        zoom = dpi / 72  # Scale factor based on DPI
        mat = fitz.Matrix(zoom, zoom)
        pix = page.get_pixmap(matrix=mat, alpha=False)

        # Convert pixmap to image
        image_bytes = io.BytesIO(pix.tobytes("png"))
        img = Image.open(image_bytes)
        return img
    except Exception as e:
        print(f"Error during PDF conversion: {str(e)}")
        return None

# Helper: Convert inches to pixels
def inches_to_pixels(inches, dpi=600):
    return int(inches * dpi)

# Step 2: Adjust image dimensions and brightness
def adjust_image(pdf_file, height_in, width_in, brightness):
    img = pdf_to_image(pdf_file)
    if img is None:
        return "Unable to convert PDF to image."

    try:
        # Convert dimensions from inches to pixels
        height_px = inches_to_pixels(height_in)
        width_px = inches_to_pixels(width_in)

        # Resize with high-quality resampling
        img_resized = img.resize((width_px, height_px), Image.LANCZOS)

        # Apply anti-aliasing filter for smooth edges
        img_smoothed = img_resized.filter(ImageFilter.SMOOTH)

        # Adjust brightness
        enhancer = ImageEnhance.Brightness(img_smoothed)
        img_bright = enhancer.enhance(brightness)

        return img_bright
    except Exception as e:
        print(f"Error during image adjustment: {str(e)}")
        return "Error adjusting the image."

# Gradio Interface
iface = gr.Interface(
    fn=adjust_image,
    inputs=[
        gr.File(label="Upload PDF"),
        gr.Number(label="Height (inches)", value=5.0),
        gr.Number(label="Width (inches)", value=4.0),
        gr.Slider(minimum=0.5, maximum=2, step=0.1, value=1.0, label="Brightness"),
    ],
    outputs="image",
    title="Plate Design Creation - Convert & Adjust PDF Page",
    description="Upload a PDF containing a technical diagram or nameplate. Adjust the dimensions and brightness for optimal clarity."
)

# Launch the interface
iface.launch()