barteled

Slideshow background adds a full size, smooth transition slideshow to the background of a WordPress site. Images can be selected from the media library or uploaded via drag-and-drop. Every page load will begin at a random position in the image loop so that users are not presented with the same start image every page change.
Additionally, the images maintain their aspects ratios during resize and turn off for mobile users.
This plug-in was conjured up by a nerd at <a href="http://think-bowl.com/" title="It's less of a tank and more of a bowl." rel="nofollow ugc">Think Bowl</a>

Simple Slideshow Background

Display a full size slideshow in the background featuring images from the media library.

WP Company

This plugin makes managing background images or videos effortless by allowing you to set a focus point that stays consistent. Regardless of how the media is resized or the background changes, the focus point ensures that the most important part of your media remains visible and centered.
Ideal for responsive designs and dynamic backgrounds, this tool ensures your media always looks polished and professional on any screen size or resolution.
🚀 See the plugin in action on <a href="https://www.wpcompany.nl/" title="The WordPress specialist" rel="nofollow ugc">WP Company</a>

Media Focus Point

The Media Focus Point Plugin ensures the key area of an image or video stays visible, regardless of resizing or layout changes.

Simple Slideshow Background vs Media Focus Point