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Getting started with Vi.S.In

July 22, 2026 · 5 min read

Vi.S.In measures joint angles from ordinary photos and video. No sensors, no markers, no lab — a neural network finds 26 points on the body in every frame and turns them into numbers you can plot, compare, and track. Here's the five-minute tour.

1. Drop in a photo or video

Open the analyzer and drag a file onto the drop zone (or click to browse). Photos are analyzed instantly and never leave your device. A video is uploaded briefly so we can decode it into frames — a 15-second clip takes a moment — and it is deleted the moment that finishes; it is never stored. Detection itself runs privately in your browser.

For best results, film one person, well lit, with the whole body in frame. Side-on views work best for most sport analysis.

2. Get poses

For video, press Get Poses. You'll see the skeleton drawn over each frame as detection runs — 26 keypoints from head to toes, including heels and toes, so even foot angles are measurable. When it finishes, scrub the timeline, play the clip, or step frame by frame.

3. Read the angles

Below the player, the angle table lists 22 joint-angle pairs — knees, elbows, trunk lean, hip angle, ankle angle, and more. Toggle Show on any pair to plot it over time on the chart and draw its live value on the video. Opposite and Flip change how an angle is measured (for example, flipping a "to vertical" angle so it reads as degrees of lean). You can also set a target range on any pair — the table cells turn green, amber, or red as the value moves against it.

4. Skip the setup with a preset

The Angle presets panel configures all of that in one click. Built-ins cover squats, golf swings, running gait, and bike fitting — each one switches on the relevant angles and loads evidence-based target ranges. Dial in your own combination and save it as a personal preset.

5. Fix the model when it's wrong

Pose detection is good, but not perfect. Edit Keypoints lets you drag any point to the right spot (zoom and pan for precision); Smooth Poses removes frame-to-frame jitter from the angle curves. Both are reversible.

6. Save, compare, share

With a free account you can save analyses to your Library, watch your progress over time, and create public share links. Compare puts two clips side by side on one timeline — before vs. after, you vs. a reference — and adds a delta column to the table. Or export an annotated image straight from the canvas.

That's the whole loop: film, drop, detect, read, adjust. The live webcam mode does the same thing in real time — useful for checking positions as you hold them.