ruby-on-rails - ActiveStorage 变体组合

Question

我需要给图片加水印，cmd ImageMagick 命令

convert image.png watermark.png -composite target.jpg 

或

composite -watermark 30% -tile watermark.png image.png target.jpg

如何使用 ActiveStorage::Variant 执行此操作？

Answer 1

试试这个:

def medium_img_watermark
    if self.img_first.attached?
      self.img_first.variant(resize: '1200', quality: 75, density: 96,
                             combine_options: {
                              gravity: 'center',
                              draw: 'image Over 0,0 0,0 "public/logo_white.png"'
                            }).processed
    end
  end