Colin Bendell writes about a new and particularly weird addition to Safari Technology Preview in this excellent post about the evolution of animated images on the web. He explains how we can now add an MP4 file directly to the source of an img tag. That would look something like this:
The idea is that that code would render an image with a looping video inside. As Colin describes, this provides a host of performance benefits:
Animated GIFs are a hack. [...] But they have become an awesome tool for cinemagraphs, memes, and creative expression. All of this awesomeness, however, comes at a cost. Animated GIFs are terrible for web performance. They are HUGE in size, impact cellular data bills, require more CPU and memory, cause repaints, and are battery killers. Typically GIFs are 12x larger files than H.264 videos, and take 2x the energy to load and display in a browser. And we’re spending all of those resources on something that doesn’t even look very good – the GIF 256 color limitation often makes GIF files look terrible...
By enabling video content in img tags, Safari Technology Preview is paving the way for awesome Gif-like experiences, without the terrible performance and quality costs associated with GIF files. This functionality will be fantastic for users, developers, designers, and the web. Besides the enormous performance wins that this change enables, it opens up many new use cases that media and ecommerce businesses have been yearning to implement for years. Here’s hoping the other browsers will soon follow.
This seems like a weird hack but, after mulling it over for a second, I get how simple and elegant a solution this is. It also sort of means that other browsers won’t have to support WebP in the future, too.