Once you install the plugin, it will start converting images using the default settings (no server redirects). Note that editors of the website will not be served the WebP images when logged in.

Server Redirects are an option if you want your server to redirect the files instead of the Concrete CMS process. This may have a performance benefit.

Go to System & Settings > Optimization > WebP Settings to change the default settings:

Setings are documented on the page but here is a recap:

General Settings

  • Browser WebP Autodetect
    • On: Your JPG & PNG images will be served in WebP format when the visiting browser supports it.
    • Off: The original image is served.
  • WebP Image Quality
    • Auto maintains the same quality as the source image, otherwise specify an integer (0-100). Note that changing this setting may not make a difference on some servers, depending on PHP extensions.
    • Quality: [0 = low quality & tiny files, 75 = default, 100 = near lossless & huge files]
  • Force Reconvert
    • On: Existing (cached) WebP images will be discarded and reconverted. This is useful when the WebP Image Quality setting is changed and you want to regenerate WebP images.
  • Dynamic Urls

Server Redirect Settings

Warning: This feature is experimental and does not work on all environments. If you are not a developer, please use only the General Settings. We will are not actively supporting this functionality due to environment differences.

  • Server Redirects
    • Enabled if using Apache or Nginx redirects. Will automatically enable if Apache Redirects are on.
  • Apache htaccess Rule
    • On: your htaccess file will be modified for WebP image processing.
  • Nginx Settings
    • Just gives you an example of how to configure Nginx. Your settings may vary. Sorry we are not Nginx admins and will not support these settings.
  • Cache Control Header
    • Adjust the cache-control HTTP header to specify browser caching policies for your WebP image server responses.
  • WebP Conversion Failure
    • Select failure option. (if WebP conversion fails)
  • Emit 'Vary: Accept' Header
    • If applies, consult your CDN documentation for more information on your particular use case.

If server redirects do not work or if you have other issues, please see our FAQs page before submitting a support request.