Update app.py

app.py

@@ -33,7 +33,13 @@ def downscale_pdf(pdf_file, max_width=3000, dpi=150):
         with open(output_pdf_path, "wb") as f:
             f.write(img2pdf.convert(downscaled_images))
 
-        return output_pdf_path
+        # ✅ Gradio返却用に一時ファイルにコピー
+        final_pdf_file = tempfile.NamedTemporaryFile(delete=False, suffix=".pdf")
+        with open(output_pdf_path, "rb") as src, open(final_pdf_file.name, "wb") as dst:
+            dst.write(src.read())
+
+        return final_pdf_file.name
+
 
 with gr.Blocks() as demo:
     gr.Markdown("## PDFダウンサイザー for Audiveris")