How to stabilize shaky video with AI (and when crop hurts)

Stabilization always spends pixels

To stabilize shaky video with AI, let the stabilizer track and smooth the camera motion, then accept some crop: every stabilizer trims or warps the frame edges to hide the shake, and stronger smoothing costs more edge. Check the framing in the preview; if the crop cuts into the subject, keep the original take. Locally, use Video Stabilization.

Steadiness vs crop

A practical local pass

1. Pick a representative shaky segment (walking talk, vehicle, run)
2. Start in Automatic in video stabilization
3. Check edges and verticals — over-smooth looks floaty
4. Combine with AI Video Enhancer only after motion is acceptable

KwaFlux previews stabilization locally for 5, 15 or 30 seconds, so you can reject a mode that eats too much framing before you burn a full export.

When stabilization will not save the take

Rolling shutter jello, extreme whip pans, and missing frames need a reshoot or a different edit. Stabilization is for recoverable handshake — not for rewriting physics.

Choose the mode on the preview before you export

The mode is the control, and crop is the cost it prints on the frame. The stabilizer keeps a steady window by moving the picture against the shake, so whatever falls outside that window is cut. Start in Automatic. It drops ordinary handshake, keeps the moves you meant, and trims the same fixed margin on every clip, so you can still see whether the framing survived. Subject Lock works the other way round. You drag a box around the subject on the paused preview, and KwaFlux holds that subject where it was for the whole clip. Its crop is set once for the clip, from how far the shot drifts, so a wandering take can lose a lot of its edges. Neither mode keeps every edge and also locks the shot like a tripod. If the preview looks zoomed in, that is the crop doing what you asked, not a separate zoom.

Judge the preview on edges and on verticals, the same check named in the pass above. Door frames, window bars, and the side of a building should stay straight. If they bow, or a horizon line pumps up and down, the stabilizer is being asked to repair motion the footage cannot support. Over-smooth has its own look: the camera seems to glide, a little floaty, instead of resting in the operator's hands. Quieter shake is not a reason to accept that glide. In Subject Lock, look at the box first. A box around something that moves on its own, such as a waving hand, drags the whole picture along with it. Put it on something that should stay put, such as a face or a product, and preview again. Move from Automatic to Subject Lock only when handshake is still obvious in the preview and the tighter crop still holds the subject, the headroom, and the edge detail you meant to keep.

• Walking and talking: Automatic first. Watch the head against the horizon, not only the face.
• A vehicle shot: Automatic, then follow a window pillar or the edge of the road. Vibration can look quiet while the frame still pumps.
• A run: Automatic first. Subject Lock on a run has to absorb every stride in the crop; use it only if the preview still holds the torso and the edges you need.
• When the motion is acceptable, and only then, continue in AI Video Enhancer. Sharpening a warp you later reject wastes the pass.

Stabilization previews run longer than the 1, 3 and 5 seconds other modules use: you pick 5, 15 or 30 seconds, and 5 is the default. Treat the lengths as different questions, not as a longer trailer. Five seconds shows whether a walking cadence settles. Fifteen seconds covers a move you meant to keep: a pan should still read as a pan, and a tilt should still read as a tilt, while the fast jitter drops away. Thirty seconds is the closest look at what a long, wandering take costs in crop under Subject Lock. If an intended pan turns into a drift, or a tilt seems to breathe, you are asking Subject Lock to hold a shot that was meant to move. Go back to Automatic and preview that same span again. Throw the setting out before you run a full export. The preview stays on your GPU and needs no account. Sign-in and a paid plan are needed to export, convert, repair a file, or download a file from a link.

Some shots stay poor in either mode. Rolling-shutter jello, an extreme whip pan, and gaps where frames are missing sit outside what a mode and a crop repair. A tighter crop does not straighten a frame the sensor bent, and it does not fill in pictures the camera did not record. Stabilization is for handshake you can still recover. When the preview holds a steady window but the subject smears inside it, stop. Reshoot, or cut around that moment. If the motion is acceptable, enhancement comes after stabilization, so the upscaler is not spending time on a warp you discard. You pick the mode in video stabilization, read the crop on the preview, and keep the one that still holds the shot.

The order for a whole folder is the same as for one clip. Pick the shaky stretch that represents the job, whether that's a walk-and-talk, a vehicle shot, or a run, and settle the mode on that stretch before applying it to the rest. Subject Lock can hold a static interview steady and still eat into the edges of a running shot. Automatic keeps slow camera moves, so it may leave a slow drift in an interview that was meant to be locked off. Preview each kind of motion separately. Two clips from the same scene needing different modes is a normal consequence of the crop trade-off, not a fault in the control. Export the clips whose framing you've accepted. Set aside the ones that still bend, pulse, or smear for a reshoot or a cut. A folder isn't one setting; it's a set of shots, and each one still needs its own preview before it's ready to export.