Unzoomify

# Hacked from http://github.com/dball/zoomifier/blob/master/lib/zoomifier.rb

require 'fileutils'
require 'open-uri'
require 'rubygems'
require 'rmagick'
require 'rexml/document'

class Zoomify
  TILESIZE = 256

  def self.unzoomify(url)
    tmpdir = 'tmp'
    # FileUtils.rm_rf(tmpdir) if File.exists?(tmpdir)
    # Dir.mkdir(tmpdir)       
    doc = nil
    begin
      open("#{url}/ImageProperties.xml") do |f|
        doc = REXML::Document.new(f)
      end
    rescue OpenURI::HTTPError
      return nil
    end
    attrs = doc.root.attributes
    return nil unless attrs['TILESIZE'] == '256' && attrs['VERSION'] == '1.8'
    width = attrs['WIDTH'].to_i
    height = attrs['HEIGHT'].to_i
    tiles = attrs['NUMTILES'].to_i
    @image_paths = (0 .. tiles/256).to_a
    max_level = 7
    puts "max_level: #{max_level}"
    image = Magick::Image.new(width, height)
    (0 .. width / TILESIZE).each do |column|
      (0 .. height / TILESIZE).each do |row|
        puts "getting: #{max_level}-#{column}-#{row}.jpg"
        filename = "#{max_level}-#{column}-#{row}.jpg"
        get_tile(url, tmpdir, filename)
        tile_image = Magick::Image.read("#{tmpdir}/#{filename}").first
        image.composite!(tile_image, column*TILESIZE, row*TILESIZE, Magick::OverCompositeOp)
        time_image = nil
        GC.start
      end
    end

    image.write('file.png') { }
    image = nil
    GC.start
  end
  
  def self.tile_group(num)
   "TileGroup#{num}"
  end

  def self.get_tile(url, tmpdir, filename)
    return filename if File.exists? "#{tmpdir}/#{filename}"    
    @image_paths.each do |path|
      begin                                                                                       
        open("#{tmpdir}/#{filename}", 'wb') {|f| f.write(open("#{url}/#{tile_group(path)}/#{filename}").read)}
        [path - 1, path + 1, path].each do |p|
          item = @image_paths.delete(p)
          @image_paths.unshift(item) if item
        end
        puts "path: #{path}"
        return filename
      rescue OpenURI::HTTPError
      end
    end
    nil
  end     
end

Zoomify.unzoomify('http://example.com')