Resizing arjs to make it only part of a website:

Using an iframe

Easy and simple. Interactive example here. Preview below:

Hacking into arjs. In the most

Changing the scene and video feed size

This is by no means an "universal" solution. Afaik arjs has hardcoded styles, body and window usage all over the place. I've added an "wrapperElement" to arjs, which is used instead of the body. Once arjs emits "arjs-video-loaded", the video is reparented to any element and the "wrapperElement" is set.

Example here. The modified ar.js file is here. Preview below:

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