Rob’s Tech Blog

Warning: if you’re not into building deepzoom systems, stop reading. This post will BORE YOU. Was the title not a good enough indication?

Ok good, they’re gone!

The current release of the deep zoom composer has a little bug. Ok – it has a few bugs, but I hate this one the most. You close your DeepZoom project(*.dzproj), you open your project, and viola – your images have rearranged themselves (or just disappeared). The first thing to worry about is: have you moved your files? Deepzoom projects store file references as absolute paths, which is ridiculous, but not the problem I was having.

Tori talks about this problem on the “known issues page” for the composer.

I don’t know what causes it (language settings were mentioned on that thread – I’m using en-NZ), but if you look inside the dzproj file itself, the Ids of all the composition nodes are all wrong.

More like “Deep Zoom Confounder”!

Im sure theres a fix coming, but if you’re as desperate as me, then what you’ve got to do is this:

1) put :<filename> on the end of each image’s tag

2) run the following code across your dzproj file:

using System;
using System.IO;
using System.Linq;
using System.Xml.Linq;

class Program
{
    static void Main(string[] args)
    {
        var file = string.Join(" ", args);

        XDocument d = XDocument.Load(file);

        var images = from i in d.Descendants("Image")
                     select Path.GetFileName(i.Element("File").Value);

        var imageList = images.ToList();

        var map = from e in d.Descendants("CompositionNode")
                  let tag = e.Attribute("Tag")
                  where tag != null
                  let fileName = tag.Value.Split(':').Last()
                  where images.Contains(fileName)
                  select new
                  {
                      Node = e,
                      NewId = imageList.IndexOf(fileName)
                  };

        foreach (var v in map)
        {
            v.Node.SetAttributeValue("Id", v.NewId);
        }


        d.Save(file);
        Console.Out.WriteLine("Press any key to continue");
        Console.ReadKey();
    }
}

This code will read in the xml, build a list of all the correct image ids, then update the ids of all your composition. Its not easy, but it’s a workaround!