Missing images with Deep Zoom Composer

Question

Hi,

I recently started to work with the Deep Zoom Composer in combination with Ajax.
First everything went fine and I was able to export my layout (from Deepzoom) exactly to html.

By the attempt to achieve more complex compositions regarding size and number of images the composer loses several images in the final html. The files are all equal in size and format PNG) and malfunctions randomly.

I sort out image by image to come to the point of malfunction, but it even won't work with a few images now.
If there are any solutions for my problems I would be very delighted to read them ^^

Thanks
Claas

Answer 1

Ah yes -- I'm seeing exactly this problem as well. As far as I can tell, it is a bug in DZ Composer (rather than the back-end rendering engine).

A very simple test case to repro: Make 10 8.5x11 images, at 600 DPI (mine were all the solid color Beige! ;-)). THen put them on a single horizontal row, one after the other.

I've never seen an export to a silverlight control get all 10 of those images. Usually just 6 (but not always sure which ones since they all look the same!).

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Gordon

Answer 2

Hi Gordon,

thanks for your interrest – it really agitates me that it allready worked until I added more images.
In the moment I can't even reconstruct my first version without losing images …

I hope there will be a solution coming up soon.

Thanks so far – cheers
Claas

Answer 3

Hi Claas,
  If you are worried, you might be able to see if your layout is saved by looking at the project file - I think it is just XML. Also, the images you imported are all saved seperately, so even if you've lost the layout at least you have some encoded memory of the pictures you used.

  Cheers,
    Gordon.

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Gordon

Answer 4

Hi Gordon,

thanks for the hint – but I overwrote the whole project already.
And I need to place all images, otherwise it won't make sense.

Claas

Answer 5

Hi again,

I think I made a little progress. The bug with the missing images only appears when the project is exported with ajax.
Using the silverlight export and the silverlight browser plugin – everything works fine.

I continue my work regarding these new "knowledge aspects" :)

Cheers
Claas

Answer 6

My missing images occur with the silverlight export. Looking at the .xml file generated (the sparse image scene one) I see all 10 of them in there... :-)

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Gordon

Answer 7

Hi,

it seems like the problem lies in the export between single and multiple image.
The project works fine with silverlight multiple image export – as soon I take the single image export (supported by ajax)
most of the images got lost.

It's pretty annoying that the ajax code only works with a single image.

Cheers
Claas

Answer 8

Hi,
  AH -- that might explain it. Up until last night I'd never done a collection. Also, when I tried I couldn't check because the collection stuff doesn't display out-of-the-box (it looks like I have to code up my own control, is that right?).

  The ajax limitation is a problem - the only way I can process the images I have is using a collection (memory issues). I'd hoped to make them availible via both SL and ajax. Oh well, have to wait a while for everything to catch up. :-)

  Cheers, Gordon.

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Gordon

Answer 9

Hi Gordon,

I performed some test and uploaded the results to:

http://www.ispam.de/deepzoombug/index.html

Maybe it helps to get an idea of how to fix that problem :)


Cheers
Claas

Answer 10

What is your memory usage when you are actually exporting? I am assuming that it pushes the limit of what your system can handle. Regardless of that, DZC shouldn't drop images accidentally. We should handle this much better, and I'll try to get it fixed for our next release.

Thanks,
Kirupa :)

Answer 11

Hi Kirupa,

thanks for answering. We tried to export it on several machines, starting with a powermac (12GB RAM) in Vmware, notebooks with 1-2 GB Ram and a regular PC with 4 GB Ram.
The result was evertime the same. We also chaged the pixelcount of the images – I think the main problem lies in the exact location of the failure. We were not able reproduce the error.

Cheers
Claas

Answer 12

Hi there,

I did some tests regarding the memory during the export process of deep zoom composer.
And in fact – exporting single images (it doesn't matter if you use silverlight or ajax) the computer uses nearly twice as much RAM (700 MB)
as it needs for the multiple image export (390 MB). Maybe this fact helps :)

Best
Claas

Answer 13

Hi Claas,

I have the same problem even with the April 2009 version. Since the embed-viewer service only support export to Seadragon Ajax, do you mind tell me how to embed my dz images generated as Silverlight DeepZoom type to my blog similar what the following offer for Ajax type to:

http://livelabs.com/seadragon-ajax/embed-viewer/

Thanks in advance for your time.

Hi Kirupa,

You mentioned on 3/13 that you would try o fix that issue by next release. Is there any date that this issue will be fixed? 

Regards,

Peter

Answer 14

Peter - we did update the behind-the-scenes encoding tools to address this, but you may be running into a similar, related bug that we haven't heard about yet. Could you please let me know how large the images are as you are trying to export them?

Thanks,
Kirupa

Answer 15

Hi Kirupa,

The source images folder contains 110 files in 38.1 MB. I join 96 photos together. The output folder for Seadragron Akax contains 20,011 files in 104 MB.

Please le me know if you want me to set you the files.

Thanks & Regards,

Peter

Answer 16

Hi Kirupa,

Any updates on the time frame to fix this problem? This problem make the "Embed The Viewer" web service

http://livelabs.com/seadragon-ajax/embed-viewer/ useless which is a pity.

Peter

Answer 17

Hi Kirupa,

I tried the april 09 version too, but my problem remains the same, which is very similar to Peter's. I used 33 identical images (5200x3900; approx. 4MB size each) and put they side by side. After exporting as single image (ajax or silverlight) only 5-6 images appear, as you can see here:

http://www.ispam.de/deepzoombug/index.html

I hope that this bug gets fixed, as we have so many ideas that we would like to try out with this awesome technology!

Best Regards,

Claas

Answer 18

Hi Kirupa,

It seems the problem is NOT being fix in the June version. Am I missing something???????????

Thanks

Peter

Answer 19

For me, the bug with the missing images still persists, too :(

I updated my bug report picture collection:

http://www.ispam.de/deepzoombug/index.html

Best Regards,

Claas

Answer 20

Hi peter, difflered,
We have found another way this issue occurs [something we did not fix earlier], and we'll see what we can do about fixing it in our upcoming release.

Thanks,
Kirupa

Answer 21

Hi Kirupa,

Thanks for your effort! We are totally excited about the possibilities of Deep Zoom, once these issues are fixed :)

Best Regards,

Laszlo

Answer 22

Hi Difflered,
We'll be releasing another version of DZC shortly where we feel that we properly addressed this issue...again :P

In a nutshell, the missing images are due to the system or the application running out of memory. An out of memory exception is thrown by DeepZoomTools.dll and that exception is silently swallowed. The end result is that the image or images that were being processed when the exception got thrown simply don't get exported.

The solution we took inside Deep Zoom Composer is to listen for that exception, and when that exception occurs, restart the entire export process using a much slower but less memory-intensive export process. In our tests, that seemed to work fairly well where large images that originally did not export did end up exporting - albeit at a much slower pace.

In subsequent releases, we'll try to see what can be done to optimize the export/encoding process.

Cheers!
Kirupa

Answer 23

Can you give us a hint as to the two different methods of export? I'm using the dll directly and I'm very much interested in a low memory vs high memory version of the export process. Sometimes my tool has to deal with very very large sets of images and other times they are quite small - it would be nice to opimize (some of the large sets of images require gigabytes of memory and can run only on a 64 bit system - and not very smoothly at that).

Cheers,
  Gordon.

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Gordon

Answer 24

I downloaded the version as posted in

http://blogs.msdn.com/expression/archive/2009/07/22/deep-zoom-composer-released.aspx?CommentPosted=true#commentmessage

Images are still missing!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

I am using Windows 7. Is there any thing I have to do other than uninstall the old version and install the new version.

Thanks

Peter

Answer 25

Peter, what version do you see when you go to Help | About. We've had quite a number of problems with users hitting our older download instead of the most recent one. You can see a summary of the problem here: http://blogs.msdn.com/expression/archive/2009/07/23/caching-and-deep-zoom-composer-downloads.aspx

Cheers!
Kirupa

Answer 26

Hi,

It works fine after I downloaded version 1.0. I output more than 10 compositions. Take a look if you are interested. www.peterchanphoto.com.


Thanks

Peter

Answer 27

Hi Kirupa,

after a few unsuccessful attempts with my notebook we finally managed to render the 33 image test project (each 20 mega pixel) and the result is: not a single image is missing! It seems that you guys figured out that annoying bug :)

Thanks a lot!

Laszlo

Answer 28

Can you give us a hint as to the two different methods of export? I'm using the dll directly and I'm very much interested in a low memory vs high memory version of the export process. Sometimes my tool has to deal with very very large sets of images and other times they are quite small - it would be nice to opimize (some of the large sets of images require gigabytes of memory and can run only on a 64 bit system - and not very smoothly at that).

Cheers,
  Gordon.

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Gordon

I'd be interested in this too.

Currently using Deepzoomtools.dll with VS2008 to try to create output for Seadragon Ajax viewer consisting of 1500 images of around 800x1000px in a grid (8cols x 188rows), but keep geting out of memory errors. I can get about 850 images done before it throws the exception. Running on 32bit WinXP with 4Gb of Ram.

Is there a way to catch it, force a  GC.Collect and get it to carry on where it left off?

Thanks.

Answer 29

Hi,
  In the end I had to add some extra code that would split things up into collections. A grid of about 20 or so large images, and then extra stuff to lay out the images next to each other. It was extra work, as you might imagine, but turned out to fit with things I needed anyway.

  See http://deeptalk.phys.washington.edu/deeptalks/00000053/ViewConference.html for an example.

  Cheers,
    Gordon.

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Gordon