Defer Media

Defer Media is a plugin for speed up your website and defer not needed medias which out of the screen when page loaded.
Then, when you scroll down the page, it will load images/videos/iframes automatically or pre-load it even if it it not visible yet (can be adjusted with Appearance Offset parameters).

This plugin will apply the following actions:
– Defer images (standard [img] tag and also [picture] src sets)
– Defer background images (if style=”background-image” applied for some block)
– Defer Videos ([video], [source] tags)
– Defer Youtube embedded videos (iframe)
– Defer any Iframes ([iframe] tag)

You can see plugin demo on this page:
Defer Media demo