Derivative Images

We are migrating from Omeka Classic to Omeka-S.

In Omeka Classic, I typically uploaded metadata with files using the CSVImport plugin. During item creation, multiple derivative images were also created.

I am using the Omeka 2 Import module to migrate the data to Omeka-S. From what I can see so far, each item retains a link to a fullsize image file. But, I do not see any derivative image files. How can I create thumbnails in Omeka-S? Is it necessary to use the Create Missing Thumbnails module or is there some other method? Am I missing something obvious?

Thumbnails get automatically created in Omeka S just like in Classic. Are you sure there are no derivative images being created? How are you checking?

I don’t see them in the Resources–>Items–>Media section of the admin sidebar. I also checked the media table in the database. I see only one entry per item_id. Are they stored elsewhere? Thank you!

As in Classic, the derivative images aren’t stored as additional File/Media entries or database rows. If you view one of your uploaded media by clicking through from the media browse, you should see some links on the right-hand sidebar to the derivative images.

Also, if you’re seeing the images embedded on the browse and show pages, that’s a sign the derivatives are working: we only embed the derviatives, not the originals.

The only link I see under “Derivatives” indicates that it is the “original.” I also am not seeing my images on the show or browse pages. I see only generic image icon displaying on the browse and show pages.

OK, then it sounds like derivatives are not being created.

Is it a totally different server you’re on now? Have you checked on things like whether you have ImageMagick installed?

Yes, this is a new (hosted) server. I’ll check for ImageMagick.


This topic was automatically closed 250 days after the last reply. New replies are no longer allowed.