Python 给pdf文件加水印

Question

我编写代码为 pdf 文件添加水印，但是生成的文件不包含水印。

import os
import io
from PyPDF2 import PdfReader, PdfWriter
from reportlab.lib.pagesizes import letter
from reportlab.pdfgen import canvas

folder_path = 'D:/pdf/input/'
output_folder = 'D:/pdf/output/'
image_path = 'D:/pdf/watermark.jpg'
x, y = 50, 50
page_number = 1

if not os.path.exists(output_folder):
    os.makedirs(output_folder)

for pdf_file in os.listdir(folder_path):
    if pdf_file.endswith(".pdf"):
        pdf_reader = PdfReader(open(os.path.join(folder_path, pdf_file), "rb"))
        pdf_writer = PdfWriter()

        for page_num in range(len(pdf_reader.pages)):
            pdf_page = pdf_reader.pages[page_num]
            pdf_writer.add_page(pdf_page)

            if page_num == page_number - 1:
                packet = io.BytesIO()
                can = canvas.Canvas(packet, pagesize=letter)
                can.drawImage(image_path, x, y)
                can.save()
                packet.seek(0)
                new_pdf = PdfReader(packet)
                pdf_page.merge_page(new_pdf.pages[0])
        
        with open(os.path.join(output_folder, pdf_file), "wb") as output_file:
            pdf_writer.write(output_file)

print("Image added to the specified page of all pdf files and saved in the output folder.")

我试过更改图像 position 和页码，但仍然没有效果。 我希望在 pdf 文件中的特定位置添加水印。

Answer 1

固定的

import os
import io
from PyPDF2 import PdfReader, PdfWriter
from reportlab.lib.pagesizes import letter
from reportlab.pdfgen import canvas

folder_path = 'D:/pdf/pliki/'
output_folder = 'D:/pdf/output/'
sign_path = 'D:/pdf/obraz/podpis.png'

x_position = 300
y_position = 260
width =  150
height = 150

if not os.path.exists(output_folder):
    os.makedirs(output_folder)

packet = io.BytesIO()
can = canvas.Canvas(packet, pagesize=letter)
can.drawImage(sign_path, x_position, y_position, width, height, [112,113,112,113,112,113])
can.save()
packet.seek(0)
new_pdf = PdfReader(packet)

for pdf_file in os.listdir(folder_path):
    if pdf_file.endswith(".pdf"):
        pdf_reader = PdfReader(open(os.path.join(folder_path, pdf_file), "rb"))
        pdf_merged = pdf_reader.pages[0]
        pdf_merged.merge_page(new_pdf.pages[0])
        pdf_writer = PdfWriter()
        
        for i in range(len(pdf_reader.pages)):
            if i == 0:
                pdf_writer.add_page(pdf_merged)
            else:
                pdf_writer.add_page(pdf_reader.pages[i])

                     
        with open(os.path.join(output_folder, pdf_file), "wb") as output_file:
            pdf_writer.write(output_file)

print("Watermark added to the specified page of all pdf files and saved in the output folder.")