AI Motion Brush
Move exactly what you want moving: hair, water, smoke, a flag, while the rest of the frame holds still. Selective animation from one photo. Free credits.
What can you create with AI Motion Brush?
AI motion brush on a single photo
The idea is selective animation: one part of the photo moves and everything else holds perfectly still. Hair lifting in wind, steam rising off a cup, water rippling, a flag snapping — the effect works because the stillness around the motion is what makes the motion read. Animate everything and you have an ordinary clip; animate one thing and you have something that catches the eye.
Choosing what moves and what stays
Say what moves and say what does not. 'Only the water moves; the rocks, the sky and the person stay completely still' is a better prompt than describing the motion alone, because you are giving the model an explicit constraint rather than hoping it infers one. Naming the still elements individually works better than a general instruction to keep the background frozen.
Natural loops for hair, water and cloth
Some subjects loop naturally and some do not. Hair, cloth, water, smoke, foliage and flame all have motion that returns to roughly where it started, which makes a seamless loop possible. Anything with a clear direction of travel — a person walking, a car passing — will not loop, and trying to force it produces a visible snap at the join.
Motion brush vs full image-to-video
Full image-to-video animates the whole frame and is the right choice when you want a shot. Motion brush is the right choice when you want a photograph that happens to move, which is a different and more specific effect. The second one is much more forgiving of imperfect source images, because most of the frame is not being regenerated at all.
Best models for selective motion
Kling 3.0 and Veo 3.1 respect the 'keep everything else still' instruction most reliably. PixVerse v6 is a fast, cheaper option that works well when the moving element is large and obvious. If the still parts of your frame are drifting when they should not, switching to a stronger model usually fixes it faster than rewriting the prompt again. If the still parts of your frame are drifting when they should not, switching to a stronger model usually fixes it faster than rewriting the prompt again.
What usually goes wrong, and how to avoid it
The failure is leakage: you asked for the hair to move and the whole head drifts. It happens when the still elements are not named and when the moving element is small relative to the frame. List the things that must stay frozen explicitly. If leakage persists, crop tighter so the moving element occupies more of the frame — the model has less unrelated material to reinterpret.
How to use AI Motion Brush
- 1Sign in (free)
Create a SoonMaker account in one click with Google. You'll get free credits immediately — no card required.
- 2Upload a photo or describe the shot
Most video tools start from a still image — drop one in and it becomes the first frame. For text-to-video, just describe the scene, the motion, and the camera move.
- 3Pick a model and render
Choose from 16 video models depending on what matters: Veo 3.1 for synced audio, Kling 3.0 for stylised motion, Seedance 2.0 for commercial polish. Hit Generate and download the clip.