tvwindow
Turns a TV into a window. A webcam tracks your head and the scene behind the glass moves as if it were really back there.
Runs in the browser, entirely on the device — no video leaves the machine. Calibration takes about a minute and still needs doing on the actual television.
What makes it a window rather than a 3D effect
The scene is drawn with an off-axis projection tied to where your eyes actually are. Lean left and you see around the right edge of the frame; walk closer and the view widens. That is what a window does, and it is a different thing from a 3D scene that spins when you move.
The honest problem underneath is that head-coupled perspective fights the other depth cues rather than adding to them. Both eyes see the same flat panel, so stereo vision keeps insisting the picture is flat while motion parallax insists it has depth. The build is therefore about tracking latency and plausible depth, not about tricks — a late frame breaks the illusion far more thoroughly than a crude scene does.
Where the camera goes
Physical setup turns out to be half the project. The camera's offset from the centre of the screen has to be known or the geometry is wrong everywhere, and a phone can stand in as the tracker when the TV has no usable camera of its own.
Calibration solves what it can on its own and is explicit about what it cannot, which is the part that still needs a person standing in front of the actual set.