Manual:$wgTiffThumbnailType

Thumbnail settings: $wgTiffThumbnailType
The format and MIME type to convert TIFF images to.
Introduced in version:	1.15.0 (r48462)
Removed in version:	Still in use
Allowed values:	(Array with 2 entries)
Default value:	[] (1.34+) false (1.15-1.33)
Other settings: Alphabetical | By function

Details

Array of file extension and MIME type to convert TIFF images to when sending them for inline display in web pages. By default, this is an empty array, meaning this conversion does not occur. You should set this if you have configured an image thumbnailing system that supports TIFF.

Browsers don't support TIFF inline generally, so images need to be converted to an alternate format. Note scaling should work with ImageMagick, but may not with GD scaling. Will not work on images with resolution greater than $wgMaxImageArea.

Examples

// WebP is good for most images, but there are some browsers that don't support it.
$wgTiffThumbnailType = [ 'webp', 'image/webp' ];

// PNG is lossless, but inefficient for photos.
$wgTiffThumbnailType = [ 'png', 'image/png' ];

// JPEG is good for photos, but has no transparency support. Bad for diagrams.
$wgTiffThumbnailType = [ 'jpg', 'image/jpeg' ];