With separate dedicated identifiers and matching reconstruction pipelines, while only caring about a limited number of things, as in our specializing in faces, we can reconstruct 25 to 30 independent people, their heads and shoulder tops only, in real time on a 3.4 GHz i7. Note the reconstruction is accurate only as far as it matters for FR, as in we tend to ignore hair. So the models are bald, but they have the frame to frame facial expressions for everyone. Here's a gif of a degraded lighting test at 70 fps with one head doing a 3D reconstruction independently performed each frame:
https://www.dropbox.com/s/0jtee4ofh2vdeg0/BlakeHeadMeshes.gi... I'm just visualizing the face, but the entire head and shoulder tops are reconstructed.