Mastodon 画像の変換とサイズ変更

img_converter.rb

#　lib/paperclip/img_converter.rb

# こちらのインスタンスより・・　https://github.com/imas/mastodon/blob/imastodon/lib/paperclip/img_converter.rb

media_attachment.rb

# app/models/media_attachment.rb
# 参考　https://github.com/imas/mastodon

  
# 35行目あたり
IMAGE_STYLES = {
  original: {
    geometry: '1920x1920>',
    file_geometry_parser: FastGeometryParser,
  },

#112行目あたり
before_create :prepare_description, unless: :local?
before_create :set_shortcode
before_post_process :set_type, :set_extension
after_post_process :set_extension
before_save :set_meta

#148行目あたり
def file_processors(f)
  if f.file_content_type == 'image/gif'
    [:gif_transcoder]
  elsif f.file_content_type == 'image/png'
    [:img_converter, :thumbnail]
  elsif VIDEO_MIME_TYPES.include? f.file_content_type
    [:video_transcoder]
  else
    [:thumbnail]
  end
end

#178行目あたり
def set_type
  self.type = VIDEO_MIME_TYPES.include?(file_content_type) ? :video : :image
end

def set_extension
  extension = appropriate_extension(file)
  basename  = Paperclip::Interpolations.basename(file, :original)
  file.instance_write :file_name, [basename, extension].delete_if(&:blank?).join('.')
end

resize_image.js

// app/javascript/mastodon/utils/resize_image.js

//1920まで許可
const MAX_IMAGE_DIMENSION = 1920;


//processImage 最後
  //pngだったら問答無用でjpegに　v2.4.0rc3
  if (type === 'image/png') {
    canvas.toBlob(resolve, 'image/jpeg',1);
  }else{
    canvas.toBlob(resolve, type);
  }