====== preview ======

On fly preview generation can consume a lot of memory and trigger kernel's oom killer.
As workaround install [[https://github.com/nextcloud/previewgenerator|Preview Generator]] app.


  * Install the app
  * Configure the app (see below).
  * Enable the app
  * Run ''./occ preview:generate-all'' once after installation.
  * Add a (system) cron job for ''./occ preview:pre-generate''. I run it every 10 minutes.

Generated Previews are stored in ''data/appdata_$instanceid/preview/''


===== recommended configuration =====

From: [[http://web.archive.org/web/20220531113922/https://ownyourbits.com/2019/06/29/understanding-and-improving-nextcloud-previews/|Understanding and improving Nextcloud Previews]]

<code bash>
occ config:app:set previewgenerator squareSizes --value="32 256"
occ config:app:set previewgenerator widthSizes  --value="256 384"
occ config:app:set previewgenerator heightSizes --value="256"
occ config:system:set preview_max_x --value 1024
occ config:system:set preview_max_y --value 1024
occ config:system:set jpeg_quality --value 60
occ config:app:set preview jpeg_quality --value="60"
</code>