Facebooks paper on their technology is quite amazing: https://dl.acm.org/doi/10.1145/3450550.3465338 https://dl.acm.org/doi/10.1145/3450550.3465338 I'm guessin

Facebooks paper on their technology is quite amazing: https://dl.acm.org/doi/10.1145/3450550.3465338 https://dl.acm.org/doi/10.1145/3450550.3465338 I'm guessing (?) Apple's approach is similar.