https://thenextweb.com/artificial-intelligence/2018/10/16/google-explains-the-magic-behind-the-pixel-3s-super-res-zoom/

Google Pixel 3’s camera has a lot of impressive tricks up its sleeve. One of them is Super Res Zoom, which improves digital zoom for clear pictures, and allows for decent results when working with a single-lens setup like the one on the Pixel 3.

The company’s AI team explained in a blog post today that the camera zooms in before taking a picture, rather than shooting a picture first and then cropping it. That helps it improve the image quality later with special algorithms: