PDF添加水印（Python实现）

柔情只为你懂 2023-06-08 06:37 15阅读 0赞

from PyPDF2 import PdfFileWriter, PdfFileReader
    from reportlab.lib.units import cm
    from reportlab.pdfgen import canvas
    
    
    # 创建文字pdf
    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(10 * cm, 5 * cm)
    
        # 设置字体
        c.setFont("Helvetica", 80)
        # 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(0.6)
        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()
    
    
    # create_watermark('walker')
    
    
    # 制作图片水印pdf
    def create_watermark(f_jpg, f_pdf):
        w_pdf = 20 * cm
        h_pdf = 25 * cm
    
        c = canvas.Canvas(f_pdf, pagesize=(w_pdf, h_pdf))
        c.setFillAlpha(0.5)  # 设置透明度
        # 这里的单位是物理尺寸
        print(c.drawImage(f_jpg, 12 * cm, 17 * cm, 6 * cm, 6 * cm))
        c.save()
    
    
    # 所有路径为绝对路径
    def add_watermark(pdf_file_in, pdf_file_mark, pdf_file_out):
        pdf_output = PdfFileWriter()
        pdf_input = PdfFileReader(open(pdf_file_in, 'rb'))
        # PDF文件被加密了
        if pdf_input.getIsEncrypted():
            print('该PDF文件被加密了.')
            # 尝试用空密码解密
            try:
                pdf_input.decrypt('')
            except Exception as e:
                print('尝试用空密码解密失败.')
                return False
            else:
                print('用空密码解密成功.')
    
        # 获取PDF文件的页数
        pageNum = pdf_input.getNumPages()
        # 读入水印pdf文件
        pdf_watermark = PdfFileReader(open(pdf_file_mark, 'rb'))
        # 给每一页打水印
        for i in range(pageNum):
            page = pdf_input.getPage(i)
            page.mergePage(pdf_watermark.getPage(0))
            page.compressContentStreams()  # 压缩内容
            pdf_output.addPage(page)
            print("第{}页".format(i))
    
        with open(pdf_file_out, 'wb') as out:
            pdf_output.write(out)
    
    
    if __name__ == '__main__':
        f_pdf = "mark.pdf"
        create_watermark('b.jpg', f_pdf)
        add_watermark("a.pdf", f_pdf, "c.pdf")

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzM3NTk4MDEx_size_16_color_FFFFFF_t_70][]![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzM3NTk4MDEx_size_16_color_FFFFFF_t_70 1][]

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzM3NTk4MDEx_size_16_color_FFFFFF_t_70 2][]

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzM3NTk4MDEx_size_16_color_FFFFFF_t_70 3][]

# pip3 install pdf2image
    # sudo yum install poppler-cpp-devel
    # https://github.com/Belval/pdf2image
    # apt-get install poppler-utils
    # 中文支持
    # https://github.com/StellarCN/scp_zh/blob/master/fonts/SimSun.ttf
    # D:\python\Lib\site-packages\reportlab\fonts

import os
    
    from PIL import Image
    from PyPDF2 import PdfFileWriter, PdfFileReader
    from pdf2image import convert_from_path
    
    
    # pdf转png
    def pdf_pic(fn):
        pages = convert_from_path(fn)
        file_name = fn.split('.')[0]
        for i in range(0, len(pages)):
            new_name = file_name + str((i + 1))
            pages[i].save("" + new_name + ".png", 'PNG')
            print("生成图片：{}".format(new_name))
    
    
    # 图片添加水印
    def pic_add_watermark(fn, watermark):
        file_name = fn.split('.')[0]
        list = os.listdir(os.getcwd())
        i = 0
        file_list = []
        # 寻找文件列表
        for file in list:
            if file_name in file and file.endswith(".png"):
                print(file)
                file_list.append(file)
                i = i + 1
        print(file_list)
        print(i)
        file_list.sort()
        # 图片合成
        for file in file_list:
            background = Image.open(file)
            foreground = Image.open(watermark)
            background.paste(foreground, (background.size[0] - foreground.size[0] - 200, 150), foreground)
            background.save(file)
    
        im_list = []
        for each_image in range(i):
            try:
                img = Image.open(file_name + str((each_image + 2)) + ".png")
            except:
                continue
            if img.mode == "RGBA":
                img = img.convert('RGB')
                im_list.append(img)
            else:
                im_list.append(img)
        new_pdf = file_name + "_watermark.pdf"
        if not os.path.isfile(file_name + "_watermark.pdf"):  # 无文件时创建
            fd = open(new_pdf, mode="w", encoding="utf-8")
            fd.close()
        pdf = Image.open(file_list[0])
        # 保存pdf
        pdf.save(new_pdf, "PDF", resolution=100.0, save_all=True, append_images=im_list)
        # 删除图片
        for file in file_list:
            os.remove(file)
        return new_pdf
    
    
    # 所有路径为绝对路径
    def add_watermark(pdf_file_in, pdf_file_mark, pdf_file_out):
        pdf_output = PdfFileWriter()
        input = open(pdf_file_in, 'rb')
        pdf_input = PdfFileReader(input)
        # PDF文件被加密了
        if pdf_input.getIsEncrypted():
            print('该PDF文件被加密了.')
            # 尝试用空密码解密
            try:
                pdf_input.decrypt('')
            except Exception as e:
                print('尝试用空密码解密失败.')
                return False
            else:
                print('用空密码解密成功.')
    
        # 获取PDF文件的页数
        pageNum = pdf_input.getNumPages()
        # 读入水印pdf文件
        pdf_watermark = PdfFileReader(open(pdf_file_mark, 'rb'))
        # 给每一页打水印
        for i in range(pageNum):
            page = pdf_input.getPage(i)
            page.mergePage(pdf_watermark.getPage(0))
            page.compressContentStreams()  # 压缩内容
            pdf_output.addPage(page)
            print("第{}页".format(i))
    
        with open(pdf_file_out, 'wb') as out:
            pdf_output.write(out)
        input.close()
    
    
    file = 'aaaa.pdf'
    # 打水印生成pdf
    file_name = file
    print(file)
    pdf_pic(file_name)
    new_pdf = pic_add_watermark(file_name, "a.png")
    # 添加文字水印
    f_pdf = 'mark.pdf'
    add_watermark(new_pdf, f_pdf, file_name)
    os.remove(new_pdf)

![20191116113214667.png][]

**这种方式不会产生白底！！！！！！！**

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzM3NTk4MDEx_size_16_color_FFFFFF_t_70]: https://img-blog.csdnimg.cn/20191017105050405.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzM3NTk4MDEx,size_16,color_FFFFFF,t_70
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzM3NTk4MDEx_size_16_color_FFFFFF_t_70 1]: /images/20230531/3e5cd802295d4733abc730bd17cad044.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzM3NTk4MDEx_size_16_color_FFFFFF_t_70 2]: /images/20230531/e1a7cf9f16d24fef94694f3a789eb36f.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzM3NTk4MDEx_size_16_color_FFFFFF_t_70 3]: /images/20230531/f41a18e7d9404d8091ddd5b72ca0dd73.png
[20191116113214667.png]: /images/20230531/60e0d1425a9a411c8c70d3f37e8b916d.png