Error creating thumbnail for PDF Files

I have the current release of Omeka, running on a new Centos server. When I add a new item with a pdf file, it does not create the thumbnail for the item. I found this topic, Thumbnails for PDF files are not being created and looked at the stackoverflow solution which requires changing policy.xml in ImageMagick.

Here are the error messages I got from convert:

convert 0065f6a2a36eac3e9f4bf451fc1c57cc.pdf test.pdf

convert-im6.q16: not authorized `0065f6a2a36eac3e9f4bf451fc1c57cc.pdf' @ error/constitute.c/ReadImage/412.

convert-im6.q16: no images defined `test.pdf' @ error/convert.c/ConvertImageCommand/3258.

Loosening security like that doesn’t seem to me to be the best way to do things, especially on a server that supports more than just Omeka. Has anyone come up with other possible solutions?

Thanks for any help,


If the ImageMagick policy file forbids PDFs, there’s no way to make it open them. Other than editing the policy, of course.

The other way around would be, I suppose, writing a thumbnailer that uses a different tool, either just for PDFs or for all files.