Thumbnails of documents give more visibility for PDF documents of books, reports, articles and magazines. DSpace filter-media script extracts the PDF files for full-text search and thumbnail creation. and after submitting an item. Here is the view of an item without a thumbnail,
Filter-Media script can run either individually after submission of an item for the instant result. Apply the following command to run filter-media,
sudo /dspace/bin/dspace filter-media
The filter-Media command can be added to Crontab to schedule the filter-media command. Add these cron settings under the Linux user account which is running Tomcat (and owns the dspace installation directory).
crontab -e
If the DSpace run on a 24x7 working server machine, add the following entries into the Crontab,
# Run the media filter at 03:00 am every day.
0 3 * * * /dspace/bin/dspace filter-media
If you would like to change the timing, add a convenient time. See the different Cron time examples available here. See the thumbnails along with the item after applying the filter-media script.
References
Media filters for Transforming DSpace Content
https://wiki.lyrasis.org/display/DSDOC7x/Mediafilters+for+Transforming+DSpace+Content
https://wiki.lyrasis.org/display/DSDOC7x/Mediafilters+for+Transforming+DSpace+Content