What can a surf video actually tell you?

A moving rider. A moving wave. Often, a moving camera.

A surf clip is a tricky thing to measure. The camera might pan or zoom. The rider turns towards it, then away. Spray hides a foot. The wave changes shape underneath them. Movement across the screen is a mixture of all of those things.

Ride Studio brings together several computer-vision algorithms and geometric calculations to separate them. Different stages track the rider, estimate body pose, follow wave boundaries and account for the camera. We then check whether those observations make sense together over time.

Start with the body.

We estimate the positions of the rider’s joints in each usable frame, then build a three-dimensional estimate of their movement. That lets you look at a pose from above or from the side, as well as over the original footage.

From that reconstruction we calculate body extension, knee and hip bend, stance width, shoulder and hip rotation, and hand position. We also estimate how the hips sit between the front and rear foot. These measurements describe body position; a video cannot tell us how much pressure is going through each foot.

A single frame can be misleading. Looking across a sequence helps us spot inconsistent observations and see how a movement develops through a turn.

Then put the rider back on the wave.

The wave analysis follows the crest and the toe: the upper edge of the face and the point where it meets the flatter water below. Alongside the body and camera estimates, those observations help us estimate the local wave shape and the rider’s position on it.

That gives us estimates of wave height, position on the face and, where the footage supports it, ride distance and movement along the wave. Your confirmed height provides a reference for physical scale. Camera movement and perspective have to be accounted for before screen movement can mean metres.

Along-wave distance is particularly difficult. Moving sideways along a fairly uniform face can look much like the camera following you. We check the available evidence and show gaps where we cannot support a measurement.

The useful bit is seeing it happen.

The video, body views and charts follow the same moment in the ride. Pause on a turn and step through it frame by frame. In the saved examples, you can see how movement changes across a section or compare two rides side by side.

Results are processed in the background and saved, so opening a ride does not start the analysis again. We track the processing versions behind each run, which lets us investigate a result and compare changes as the technology improves.

Where the numbers need care.

These are estimates from footage. Clear, original-speed video with the whole rider, board and some surrounding wave in frame gives us much more to work with than a tiny, blurred figure or a heavily cropped edit.

We have spent a lot of time researching, testing and revising the analysis. This is still developing technology, and some clips will expose its limits. A precise-looking number does not make an uncertain reconstruction certain.

If a result looks wrong, we want to see it. Our support page explains how to ask for help.