Contents

module Sufia
  module GenericFile
    module Thumbnail
      # Create thumbnail requires that the characterization has already been run (so mime_type, width and height is available)
      # and that the object is already has a pid set
      def create_thumbnail
        return if self.content.content.nil?
        if pdf?
          create_pdf_thumbnail
        elsif image?
          create_image_thumbnail
        # elsif video?
        #   create_video_thumbnail
        end
      end

      def create_pdf_thumbnail
        retryCnt = 0
        stat = false;
        for retryCnt in 1..3
          begin
            pdf = Magick::ImageList.new
            pdf.from_blob(content.content)
            first = pdf.to_a[0]
            first.format = "PNG"
            thumb = first.scale(338, 493)
            self.thumbnail.content = thumb.to_blob { self.format = "PNG" }
            #logger.debug "Has the content changed before saving? #{self.content.changed?}"
            stat = self.save
            break
          rescue => e
            logger.warn "Rescued an error #{e.inspect} retry count = #{retryCnt}"
            sleep 1
          end
        end
        return stat
      end

      def create_image_thumbnail
        img = Magick::ImageList.new
        img.from_blob(content.content)
        # horizontal img
        height = Float(self.height.first.to_i)
        width = Float(self.width.first.to_i)
        scale = height / width
        if width > height
          if width > 150 and height > 105
            thumb = img.scale(150, height/scale)
          else
            thumb = img.scale(width, height)
          end
        # vertical img
        else
          if width > 150 and height > 200
            thumb = img.scale(150*scale, 200)
          else
            thumb = img.scale(width, height)
          end
        end
        self.thumbnail.content = thumb.to_blob
        #logger.debug "Has the content before saving? #{self.content.changed?}"
        self.save
      end
    end
  end
end

Version data entries

6 entries across 6 versions & 1 rubygems

Version	Path
sufia-0.1.0	lib/sufia/generic_file/thumbnail.rb
sufia-0.0.8	lib/sufia/generic_file/thumbnail.rb
sufia-0.0.7	lib/sufia/generic_file/thumbnail.rb
sufia-0.0.6	lib/sufia/generic_file/thumbnail.rb
sufia-0.0.5	lib/sufia/generic_file/thumbnail.rb
sufia-0.0.4	lib/sufia/generic_file/thumbnail.rb