gistfile1.rb

raw_message = STDIN.read
email = TMail::Mail.parse(raw_message)
if email.has_attachments?
  email.attachments.each do |attachment|
    image = attachment.read
    filename = attachment.original_filename
  end
elsif email.content_type == 'image/jpeg'
  image = email.body
  filename = email.header['content-disposition'].params['filename']
end