Python缩放pdf到A4页面大小

使用PyMuPDF即可轻松达成，原地址：

how to scale all page to A4 · Issue #23 · pymupdf/PyMuPDF-Optional-Material · GitHub

具体方法：

import fitz

src = fitz.open("source.pdf")
doc = fitz.open()
for ipage in src:
    fmt = fitz.paper_rect("a4")
    page = doc.new_page(width = fmt.width, height = fmt.height)
    page.show_pdf_page(page.rect, src, ipage.number)

doc.save("reformatted.pfd")