The Media Converter shrinks your image payload by converting uploads to modern WebP or AVIF, and ships a bulk tool to convert the images already in your Media Library. It rides WordPress core’s own image pipeline, so it optimises without corrupting attachment records.
Where: WP Admin → Tiger Blocks → Tools → Media Converter. Enable it under Modules & Widgets → Media Converter.
Two ways it works
- On upload — new images are force-converted to your chosen format as WordPress generates their sub-sizes, so every new upload is already optimised.
- Bulk convert — a one-click tool re-runs existing Media Library images through the same pipeline, processed in small batches over AJAX so a large library never hits a PHP timeout.
Settings
- Target format — WebP, AVIF, or Both (WebP as the primary file plus AVIF siblings of every size for a
<picture>/CDN setup). - Quality — independent sliders for WebP (default 82) and AVIF (default 55).
- Lossless — re-encode the full image losslessly from the kept original (needs Imagick).
- Keep backup — retain WordPress’ original upload so images can be restored; turn off to reclaim disk space.
- Max width — downscale oversized originals before conversion (overrides WordPress’ default 2560px “big image” threshold).
- Source types — convert JPEG, PNG and/or GIF. GIF is off by default because converting an animated GIF would drop its animation.
How it stays safe
Conversion uses core’s image_editor_output_format filter rather than rewriting post_mime_type by hand, so links, thumbnails and srcsets stay valid. Encoding prefers Imagick (needed for true-lossless and reliable AVIF) and falls back to the site’s GD editor. When an attachment is deleted, the AVIF siblings the converter created are cleaned up too.
Per-file control
Every image gains a Tiger Media Converter field in its Attachment Details, with a Skip this file checkbox and a converted/not-yet-converted status, so you can exempt a specific asset.
Troubleshooting
The bulk tool says to enable the converter first
Bulk conversion re-uses the live upload pipeline, which only runs when the converter is switched on. Tick Enable, save your format and quality settings, then run the bulk tool.
AVIF files are not being produced
AVIF (and true-lossless) output relies on the Imagick PHP extension with AVIF/libheif support. If the host only offers GD, WebP still works but AVIF may not; ask your host to enable Imagick with AVIF, or use WebP as the target.