Photophone
Sharing data between two screens, using only photons.
Send (unicast)
Display data to a single receiver.
Receive (unicast)
Watch a single sender with your camera.
Broadcast (sender)
Fountain-loop a file to any watching receiver.
Broadcast (receiver)
Tune in to an ongoing broadcast; saves as a file.
Back-channel tx
M11 test: render a hello back-channel frame.
Back-channel rx
M11 test: decode back-channel frames from a camera.
Audio bc tx
M11b test: FSK over Web Audio (sender side).
Audio bc rx
M11b test: mic decodes audio back-channel.