Python给PDF文件打水印

# -*- coding: utf-8 -*-
from PyPDF2 import PdfFileWriter, PdfFileReader
from reportlab.pdfgen import canvas
from reportlab.lib.units import cm
import sys

def create_watermark(content):
    # 默认大小为21cm*29.7cm
    c = canvas.Canvas("mark.pdf", pagesize=(30 * cm, 30 * cm))
    # 移动坐标原点(坐标系左下为(0,0))
    c.translate(3 * cm, 5 * cm)


    c.setFont("Helvetica", 60)
    # 指定描边的颜色
    # c.setStrokeColorRGB(0, 1, 0)
    # 指定填充颜色
    c.setFillColorRGB(0, 1, 0)
    # 画一个矩形
    # c.rect(cm, cm, 7 * cm, 17 * cm, fill=1)

    # 旋转45度，坐标系被旋转
    c.rotate(45)
    # 指定填充颜色
    # c.setFillColorRGB(0.6, 0, 0)
    # 设置透明度，1为不透明
    c.setFillAlpha(0.3)
    # 画几个文本，注意坐标系旋转的影响
    c.drawString(3 * cm, 0 * cm, content)
    c.setFillAlpha(1.0)
    # c.drawString(6 * cm, 3 * cm, content)
    # c.setFillAlpha(1)
    # c.drawString(9 * cm, 6 * cm, content)

    # 关闭并保存pdf文件
    c.save()




def watermark(input_pdf, output, watermark):
    watermark_obj = PdfFileReader(watermark)
    watermark_page = watermark_obj.getPage(0)

    pdf_reader = PdfFileReader(input_pdf)
    pdf_writer = PdfFileWriter()

    # 给所有页面添加水印
    for page in range(pdf_reader.getNumPages()):
        page = pdf_reader.getPage(page)
        page.mergePage(watermark_page)
        pdf_writer.addPage(page)

    with open(output, 'wb') as f:
        pdf_writer.write(f)



if __name__ == '__main__':
    origin_file = sys.argv[1]
    out_file = sys.argv[2]
    mark = sys.argv[3]

    # create_watermark('水印文字')  # 生成mark文件
   
    watermark(input_pdf=origin_file,output=out_file,watermark=mark)