how to work with attachment-fu in 100mb size zip file?

Question

I am uploading 100 mb file in attachment-fu , i have given size also upto 128mb in the model file too. But when i attach zip file, the files started repeating by it self ,and if i upload same 20mb file it works perfaclty fine. And if i do this process on the server it takes so much process and load too, is there any way to solve thsi ? my code of model is

has_attachment  :storage => :file_system,
:max_size => 128.megabytes

validates_as_attachment

def self.build_from_zip(ss,user,gallary)
zipfile = Zip::ZipFile.open(ss.temp_path)
zipfile.each do |entry|
  if entry.name.include?("/")
    entry.name = entry.name.split("/").last
    entry.name = "" if entry.name.nil?
  end
  if entry != ""
    if entry.directory?
      next
    elsif entry.name.include?("/")
      next
    else
      screen =Upload.new
      screen.filename = entry.name
      screen.description = ss.description
      screen.user_id = user
      screen.gallaries = Gallary.find(gallary) if gallary
      screen.temp_data = zipfile.read(entry.name)
      mime = MIME::Types.type_for(entry.name)[0]
      screen.content_type = mime.content_type unless mime.blank?
      screen.save! unless screen.content_type.blank?
      if mime.content_type.include?("video")
        screen.convert
      end
      @upload = Upload.find_by_id(screen.id)
      if @upload.content_type.include?("video")
        @upload.video= 'video'
        @upload.save_thumbnail
        @upload.save
        @thumb = Thumbnail.find_by_id(@upload.thumbnail.to_i)
        @thumb.parent_id = @upload.id
        @thumb.thumbnail = 'thumb'
        @thumb.save
      else
        image = Magick::ImageList.new("public/"+ @upload.public_filename)
        screen.date_taken = DateTime.strptime(image.get_exif_by_entry('DateTime')[0][1], "%Y:%m:%d %H:%M:%S") unless image.get_exif_by_entry('DateTime')[0][1].nil?
        screen.model  = image.get_exif_by_entry('model')[0][1]
        screen.camera  = image.get_exif_by_entry('make')[0][1]
        screen.iso  =  image.get_exif_by_entry('ISOSpeedRatings')[0][1]
        screen.save
      end
    end
  end
end

end