Thanks, Mike, for those great questions.
Regarding the first topic:
Correct, though the initial connection is done via the server, all video, audio and images are delivered using a peer-to-peer delivery model (no intermediary server for transmission).
Regarding your second topic:
Our video streams are adaptive where we will adapt video resolution and frame rate to maintain a real-time view of the local user’s camera feed.
- With an up-link bandwidth of 2.8 Mbps, the video resolution will be 1.280 x 720 p and the frame rate (target) will be 31 FPS
- With an up-link bandwidth of 1.0 Mbps, the video resolution will be 640 x 360 p and the frame rate (target) will be 31 FPS
- With an up-link bandwidth of 0.5 Mbps, the video resolution will be 320 x 180 p and the frame rate (target) will be 30 FPS (with an ~1 sec lag)
Below 500 Kbps (when the Remote Expert experiences choppy video where details cannot be made out) – we encourage the Remote Expert to enable our “low bandwidth mode”.
Then Vuforia Chalk will switch from video stream to an image stream delivered over HTTPS. There will be a trade-off between real-time and quality. So the low bandwidth mode ensures a usable and clear image and still allows annotations.
So the recommendation would be to have a bandwidth higher than 500 Kbps, but Vuforia Chalk is still able to support situation with low bandwidth connections. Exactly this is one of the unique strengths of Vuforia Chalk.