app.py

import gradio as gr
from pdf2image import convert_from_path
from PIL import Image
import img2pdf
import tempfile
import os

def resize_pdf(pdf_file, width_percent, height_percent):
    width_percent = float(width_percent)
    height_percent = float(height_percent)
    
    with tempfile.TemporaryDirectory() as tmpdir:
        # PDF → 画像（全ページ）
        images = convert_from_path(pdf_file.name, dpi=200, output_folder=tmpdir)
        
        resized_images = []
        for i, img in enumerate(images):
            # リサイズ幅・高さ計算
            new_width = int(img.width * width_percent / 100)
            new_height = int(img.height * height_percent / 100)
            resized_img = img.resize((new_width, new_height), Image.LANCZOS)
            
            # 一時保存
            img_path = os.path.join(tmpdir, f"page_{i}.png")
            resized_img.save(img_path, format='PNG')
            resized_images.append(img_path)
        
        # 画像 → PDF
        output_pdf_path = os.path.join(tmpdir, "resized_output.pdf")
        with open(output_pdf_path, "wb") as f_out:
            f_out.write(img2pdf.convert(resized_images))
        
        return output_pdf_path

with gr.Blocks() as demo:
    gr.Markdown("# PDFサイズを％でリサイズ")
    pdf_input = gr.File(label="PDFファイルを選択")
    width_input = gr.Number(label="幅の倍率(%)", value=100)
    height_input = gr.Number(label="高さの倍率(%)", value=100)
    output_pdf = gr.File(label="リサイズ後のPDF")

    btn = gr.Button("リサイズ実行")
    btn.click(resize_pdf, inputs=[pdf_input, width_input, height_input], outputs=output_pdf)

demo.launch()