How Facebook’s new 3D photos work
In case you missed the teaser, 3D photos will live in your news feed just like any other photos, except when you scroll by them, touch or click them, or tilt your phone, they respond as if the photo is actually a window into a tiny diorama, with corresponding changes in perspective. It will work for both ordinary pictures of people and dogs, but also landscapes and panoramas.
It sounds a little hokey, and I’m about as skeptical as they come, but the effect won me over quite quickly. The illusion of depth is very convincing, and it does feel like a little magic window looking into a time and place rather than some 3D model — which, of course, it is.
In their system, the user takes multiple images of their surroundings by moving their phone around; it captures an image (technically two images and a resulting depth map) every second and starts adding it to its collection.
In the background, an algorithm looks at both the depth maps and the tiny movements of the camera captured by the phone’s motion detection systems. Then the depth maps are essentially massaged into the correct shape to line up with their neighbors. This part is impossible for me to explain because it’s the secret mathematical sauce that the researchers cooked up.
See the full story here: https://techcrunch.com/2018/06/07/how-facebooks-new-3d-photos-work/