Python PDF 加水印

今天药忘吃喽~ 2024-03-24 17:41 51阅读 0赞

Python PDF 加水印

from PyPDF2 import PdfWriter,PdfReader
    from reportlab.lib.units import cm
    from reportlab.pdfgen import canvas
    import reportlab.pdfbase.ttfonts
    from reportlab.pdfbase import pdfmetrics
    import os
    
    basedir=os.path.dirname(os.path.abspath(__file__))
    
    
    def create_watermark(content):
        """水印信息"""
        # 默认大小为21cm*29.7cm
        file_name = os.path.join(basedir,"../../media/mark.pdf")
        c = canvas.Canvas(file_name, pagesize=(30 * cm, 30 * cm))
        # 移动坐标原点(坐标系左下为(0,0))
        c.translate(10 * cm, 5 * cm)
        try:
            # 注册中文字体
            pdfmetrics.registerFont(reportlab.pdfbase.ttfonts.TTFont('yahei', '微软雅黑.ttf'))
            c.setFont('yahei',20)
        except:
            # 设置字体
            c.setFont("Helvetica", 30)
        # 指定描边的颜色
        c.setStrokeColorRGB(0, 1, 0)
        # 指定填充颜色
        c.setFillColorRGB(0, 0, 222,0.2)
        # 旋转45度,坐标系被旋转
        c.rotate(30)
        # 指定填充颜色
        # c.setFillColorRGB(0, 0, 0, 0.1)
        # 设置透明度,1为不透明
        c.setFillAlpha(0.1)
        # 画几个文本,注意坐标系旋转的影响
        for i in range(5):
            for j in range(10):
                a = 10 * (i - 1)
                b = 5 * (j - 2)
                c.drawString(a * cm, b * cm, content)
                c.setFillAlpha(0.1)
        # 关闭并保存pdf文件
        c.save()
        return file_name
    
    def add_watermark(pdf_file_in, pdf_file_mark, pdf_file_out):
        """把水印添加到pdf中"""
        pdf_output = PdfWriter()
        input_stream = open(pdf_file_in, 'rb')
        pdf_input = PdfReader(input_stream, strict=False)
    
        # 获取PDF文件的页数
        pageNum = len(pdf_input.pages)
    
        # 读入水印pdf文件
        pdf_watermark = PdfReader(open(pdf_file_mark, 'rb'), strict=False)
        # 给每一页打水印
        for i in range(pageNum):
            page = pdf_input.pages[i]
            page.merge_page(pdf_watermark.pages[0])
            page.compress_content_streams()  # 压缩内容
            pdf_output.add_page(page)
        pdf_output.write(open(pdf_file_out, 'wb'))