A curved wall of video memories you browse with your bare hands: point, pinch to pull one out, pinch and drag to scrub through it, swipe to move on. Hand tracking runs on your own device. It is a demonstration we built ourselves: no client commissioned it, and anything marked sample is made up and says so on screen.
What it will not tell you
A measurement taken from a capture is a guide: where a figure matters legally or commercially, the surveyed number rules, and nothing here replaces an inspection.
Eighteen short recordings on a curved wall of glass. Point to look, pinch to pull a memory towards you, pinch and drag to scrub through it, swipe to move to the next. Your webcam watches your hand; nothing else is needed, and a mouse or a finger on a touchscreen works too.
Your camera stays on your device. The hand tracker runs inside this page; no picture of you is sent anywhere, and nothing is recorded.
PointMove the cursor with your index fingermouse: just move
Quick pinchPull the memory you point at towards youmouse: click · touch: tap
Pinch and dragTurn the wall, or scrub through an open memorymouse: drag · touch: drag
SwipeOpen hand: sweep left for the next memory, right for the one before, down to go backkeys: ← → and Esc
How we built it
A wall you steer with your hand
Eighteen short memories
Each panel is an 8-second loop cut from stock footage, 854 by 480, with a keyframe every 0.4 seconds so scrubbing keeps up with your hand. A strip of ten stills per memory makes the filmstrip under an opened one. Recordings with strangers in them play as a tinted memory, never in true colour.
Hand landmarks on your device
A hand-tracking model running on your device finds 21 points on your hand in every webcam frame, in WebAssembly inside this page. Only the points are used; the picture never leaves the page.
From points to gestures
The index fingertip is the cursor, smoothed so it doesn't shiver. A pinch is the gap between thumb and index tips shrinking below a quarter of the hand's size, measured against the hand itself so it works near or far from the camera, and it has to open wider than it closed before it counts as let go. A swipe is the open hand moving across a fifth of the frame in about a sixth of a second.
The wall
Panels hang on a circle around you in 3D. Only the ones facing you play; the rest show a still, so the page doesn't ask your browser to decode eighteen videos at once. Three memories open into their 3D versions from the lab: the Dubai interchange, the forest flight and the London pavement, where you can bet on each walker's next two seconds.
Limits
One hand at a time. Keep it 40 to 80 cm from the camera, in decent light, palm towards the screen.
A pinch seen edge-on can look open, and fingers crossing in front of each other can look like a pinch, so the occasional missed or extra pinch happens. The cursor ring fills as your fingers close so you can see what the tracker sees.
The first start downloads the hand model (about 8 MB) and the tracker code once. After that everything runs locally.
On older phones the tracker can run at only a few frames a second; touch works everywhere.