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’)
