python替换PDF字体

import PyPDF2

def replace_font_in_pdf(input_path, output_path, old_font_name, new_font_name):
    with open(input_path, 'rb') as file:
        pdf = PyPDF2.PdfFileReader(file)
        writer = PyPDF2.PdfFileWriter()

        for page_num in range(pdf.getNumPages()):
            page = pdf.getPage(page_num)
            content_object = page['/Contents'].getObject()
            if isinstance(content_object, PyPDF2.generic.ArrayObject):
                content_objects = content_object
            else:
                content_objects = [content_object]

            for obj in content_objects:
                if obj.getObject().startswith(b'BT'):
                    font_name = obj[1][0].getObject()[1].getObject()
                    if font_name == old_font_name.encode():
                        obj[1][0].getObject()[1] = PyPDF2.generic.createStringObject(new_font_name)

            page.__setitem__(PyPDF2.generic.NameObject('/Contents'), content_objects)
            writer.addPage(page)

        with open(output_path, 'wb') as output_file:
            writer.write(output_file)

# 示例用法
replace_font_in_pdf('input.pdf', 'output.pdf', 'OldFont', 'NewFont')