# File lib/asciidoctor/converter/docbook5.rb, line 769
    def cover_tag doc, face, use_placeholder = false
      if (cover_image = doc.attr %(#{face}-cover-image))
        width_attr = nil
        depth_attr = nil
        if (cover_image.include? ':') && ImageMacroRx =~ cover_image
          cover_image = doc.image_uri $1
          unless $2.empty?
            attrs = (AttributeList.new $2).parse ['alt', 'width', 'height']
            if attrs.key? 'scaledwidth'
              # NOTE scalefit="1" is the default in this case
              width_attr = %( width="#{attrs['scaledwidth']}")
            else
              width_attr = %( contentwidth="#{attrs['width']}") if attrs.key? 'width'
              depth_attr = %( contentdepth="#{attrs['height']}") if attrs.key? 'height'
            end
          end
        end
        %(<cover role="#{face}">
<mediaobject>
<imageobject>
<imagedata fileref="#{cover_image}"#{width_attr}#{depth_attr}/>
</imageobject>
</mediaobject>
</cover>)
      elsif use_placeholder
        %(<cover role="#{face}"/>)
      end
    end