This documentation is not using the current rendering mechanism and will be deleted by December 31st, 2020. The extension maintainer should switch to the new system. Details on how to use the rendering mechanism can be found here.

Administrator Manual

Target group: Administrators


To install the extension, perform the following steps:

  1. Go to the Extension Manager
  2. Install the extension
  3. Load the static template



If set to false, then images are not upscaled. I.e. if one or more srcset candidates width is bigger than the original images width, then one last image candidate is created with the original images width.

On the other hand, if this setting is true, then images will be upscaled to match the widths of all given srcset candidates.

Respecting this setting was introduced with c1_adaptive_images version 0.1.5

Include third-party JavaScript (if needed)

This extension does currently not include third party JavaScript which is needed for advanced image modes and the integrator/administrator has to add them to the website.


This script is needed to render images using lazyloading and setting the sizes attribute automatically. Download it at

The script should be included early, e.g.:

page.includeJSFooterlibs.lazysizes = EXT:yourtheme/Resources/Public/Js/lazysizes.min.js


A polyfill to support the picture tag in older browsers, most notably IE11 and Opera Mini. Download it at

This script should be included early in the head of the website:

page.includeJSLibs.picturefill = EXT:yourtheme/Resources/Public/Js/picturefill.min.js

Hint: As a simpler alternative one could also use as a picture polyfill.