app.py

import gradio as gr
import subprocess

def rasterize_pdf(input_pdf):
    output_pdf = "/tmp/output.pdf"
    
    cmd = [
        "gs",
        "-o", output_pdf,
        "-sDEVICE=pdfwrite",
        "-dFILTERVECTOR",
        "-dCompatibilityLevel=1.4",
        "-dPDFSETTINGS=/screen",
        "-dNOPAUSE",
        "-dBATCH",
        "-dQUIET",
        input_pdf
    ]
    
    result = subprocess.run(cmd, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
    if result.returncode != 0:
        return f"エラー: {result.stderr.decode()}", None

    return "ラスタライズ完了", output_pdf

demo = gr.Interface(
    fn=rasterize_pdf,
    inputs=gr.File(file_types=[".pdf"]),
    outputs=[gr.Text(), gr.File()],
    title="PDFラスタライズ変換（Ghostscript）",
    description="SVGベクターPDFをビットマップ化PDFに変換し、Audiveris用に軽量化します。"
)

demo.launch()