Python为pdf文件添加水印

Question

我编写了代码为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.")

我已经尝试改变图像位置和页码，但仍然没有效果。我希望在pdf文件的特定位置添加水印。

Answer 1

FIXED

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.")