# File lib/deltacloud/drivers/mock/mock_driver.rb, line 136
  def create_image(credentials, opts={})
    check_credentials(credentials)
    instance = instance(credentials, :id => opts[:instance_id])
    raise BackendError::new(500, 'CreateImageNotSupported', '', '') unless instance.can_create_image?
    ids = Dir[ "#{@storage_root}/images/*.yml" ].collect{|e| File.basename( e, ".yml" )}
    count = 0
    while true
      next_id = "img#{count}"
      break if not ids.include?(next_id)
      count += 1
    end
    safely do
      image = {
        :name => opts[:name],
        :owner_id => 'root',
        :description => opts[:description],
        :architecture => 'i386',
        :state => 'UP'
      }
      File.open( "#{@storage_root}/images/#{next_id}.yml", 'w' ) do |f|
        YAML.dump( image, f )
      end
      image[:id] = next_id
      Image.new(image)
    end
  end