Resources slow to create previews

Offline generation of previews/alternative files

It is recommended that system administrators enable the offline job queue so that users uploading files do not have to wait while previews and alternative files are created

If the full offline job queue functionality is not desirable, there are also other legacy config values below to disable automatic preview creation upon upload:

$enable_thumbnail_creation_on_upload = false;

- or by setting

$preview_generate_max_file_size=100; (previews for smaller files will still be created. Value is in MB)

and then creating a crontab entry/scheduled task to run the script below:

/batch/create_previews.php

It is recommended that the user used to run this script is the web service account (e.g. www-data) or has the same access to avoid permissions issues.

Large videos slow or failing to create previews

There are occasions when preview generation for large video files can fail. This is often due to a large number of informational messages logged during the process.

You can try one of the following to reduce the level of informational/warning log entries, potentially speeding up the process and making it more resilient.

The parameter to include is "-loglevel error" in one of the following config entries:-

$ffmpeg_global_options

$ffmpeg_preview_options

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