Skip or disable derivative image creation

It would be useful to be able to disable derivative image creation for the purpose of bulk uploading 1000s of files. I would like the uploads to complete on their own, into the /original directory, without waiting for any image processing. I would then trigger the derivative image creation process at the end using Bulk Check ( which was formerly Derivative Images module.

Is there a simple way to modify the core config to accomplish this?

Yes, you can set the noop thumbnailer ( in your config before, then reapply your config after.

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Thanks Daniel. I would love to see this exposed in the Global Settings UI as a checkbox (maybe “temporarily disable thumbnailer” to discourage casual use).

Daniel, a question about Bulk Check. I have it installed, and I notice that the setting “Rebuild derivative images with options below” is missing something that I expected.

When I set the “NoThumbnail” setting for Omeka\File\Thumbnailer, all prior imports already had thumbnails generated. So I was expecting to simply be able to run a job to create derivative images for all items in which thumbnails do not currently exist. But, under “Options for derivative files”, I don’t see a way to indicate that.

  • Item sets
  • Ingesters to process
  • Renderers to process
  • Media types to process
  • Media ids

I hate to feel like I am the one always generating “odd” use cases. Does this use case make sense? The media database table already has a field “has_thumbnails”, so an option could be made to filter the records to just that (has_thumbnails = 0). Or perhaps a new processor “Build derivative images for items without thumbnails”?

Nevermind! It would be nice to be able to simply have a flag to check the “has_thumbnails” status, and then generate all that don’t - and it would also be nice to be able to specify by item ID - but I realized it was not hard, at least in my case, to determine the media IDs since there was a one-time switch from \ImageMagick to \NoThumbnails for the Omeka\File\Thumbnailer setting in local.config.php.

I had just never worked with media IDs before.

The simplest way is to create a temporary collection and to pull all the items you want inside.
I added the option in the last version of the module Bulk Check.

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