Python如何为图片添加水印

添加水印的主要目的是为了版权保护，使自己的图像不被抄袭或者恶意转载。网上有很多制作水印的工具，本帖介绍怎么使用Python-Pillow库给图片添加水印。

使用ImageMagick添加图片水印－Linux 添加文本水印

在图片右下角添加文字：

from PILimport Image, ImageDraw, ImageFont

# 指定要使用的字体和大小；/Library/Fonts/是macOS字体目录；Linux的字体目录是/usr/share/fonts/
font = ImageFont.truetype('/Library/Fonts/Arial.ttf', 24)

# image: 图片  text：要添加的文本 font：字体
def add_text_to_image(image, text, font=font):
  rgba_image = image.convert('RGBA')
  text_overlay = Image.new('RGBA', rgba_image.size, (255, 255, 255, 0))
  image_draw = ImageDraw.Draw(text_overlay)

  text_size_x, text_size_y = image_draw.textsize(text, font=font)
  # 设置文本文字位置
  print(rgba_image)
  text_xy = (rgba_image.size[0] - text_size_x, rgba_image.size[1] - text_size_y)
  # 设置文本颜色和透明度
  image_draw.text(text_xy, text, font=font, fill=(76, 234, 124, 180))

  image_with_text = Image.alpha_composite(rgba_image, text_overlay)

  return image_with_text

im_before = Image.open("lena.jpg")
im_before.show()
im_after = add_text_to_image(im_before, 'WTF')
im_after.show()
# im.save('im_after.jpg')

添加图片水印

fromPILimportImage, ImageDraw

defadd_watermark_to_image(image, watermark):
  rgba_image = image.convert('RGBA')
  rgba_watermark = watermark.convert('RGBA')

  image_x, image_y = rgba_image.size
  watermark_x, watermark_y = rgba_watermark.size

  # 缩放图片
  scale = 10
  watermark_scale = max(image_x / (scale * watermark_x), image_y / (scale * watermark_y))
  new_size = (int(watermark_x * watermark_scale), int(watermark_y * watermark_scale))
  rgba_watermark = rgba_watermark.resize(new_size, resample=Image.ANTIALIAS)
  # 透明度
  rgba_watermark_mask = rgba_watermark.convert("L").point(lambda x: min(x, 180))
  rgba_watermark.putalpha(rgba_watermark_mask)

  watermark_x, watermark_y = rgba_watermark.size
  # 水印位置
  rgba_image.paste(rgba_watermark, (image_x - watermark_x, image_y - watermark_y), rgba_watermark_mask)

  return rgba_image

im_before = Image.open("lena.jpg")
im_before.show()

im_watermark = Image.open("watermark.jpg")
im_after = add_watermark_to_image(im_before, im_watermark)
im_after.show()
# im.save('im_after.jpg')