How to add watermark to pictures in Python

The main purpose of adding watermarks is for copyright protection so that your images will not be plagiarized or maliciously reproduced. There are many tools for making watermarks on the Internet. This post introduces how to use the Python-Pillow library to add watermarks to images.

Use ImageMagick to add image watermark-Linux to add text watermark

Add text in the lower right corner of the picture:

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')

Add picture watermark

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')