Manual:$wgUploadStashScalerBaseUrl

From Linux Web Expert

<translate> Server URLs and file paths</translate>: $wgUploadStashScalerBaseUrl
To enable remote on-demand scaling, set this to the thumbnail base URL.
<translate> Introduced in version:</translate>1.17.0 (r86169)
<translate> Deprecated in version:</translate>1.36.0 (Gerrit change 664086; git #d08c5ba3)
<translate> Removed in version:</translate><translate> still in use</translate>
<translate> Allowed values:</translate>(string) or false
<translate> Default value:</translate>false

Details

To enable remote on-demand scaling, set this to the thumbnail base URL. Full thumbnail URL will be like $wgUploadStashScalerBaseUrl/e/e6/Foo.jpg/123px-Foo.jpg where 'e6' are the first two characters of the MD5 hash of the file name. If this is set to false, thumbs are rendered locally as needed.