Liquify Image
Liquify tool for images and video: push, bloat, pucker or twirl one spot, placed and sized with sliders. The warp never folds over itself. Nothing is uploaded.
What is a liquify tool?
A liquify tool is a kind of image warping: pixels keep their colors but move, as if the picture were printed on something soft. A push drags part of the picture along, a bloat swells it, a pucker draws it in and a twirl spins it around a point.
People use warping to correct lens distortion as well as for effects, and the same math works on every frame of a video.
How to liquify a photo or video
Pick a Brush: Push, Bloat, Pucker or Twirl, each of which is also a preset. Move Position X and Position Y over the part you want to change, then set Radius, the brush width as a share of the frame's height.
Strength sets how hard the brush pulls. For Push, Direction sets which way it goes in degrees, with 0 to the right and 90 down. The Smear up preset pushes a wide area upward.
Settings for a caricature nose, a melting picture and a stirred cup
Caricature nose: Bloat with Position X and Position Y on the tip of the nose, Radius 0.12 and Strength 0.6. At full Strength the middle of a bloat grows about three times bigger, so for a face, stay well below 1.
Melting picture: Push with Direction 90, Radius 0.45 and Strength 1. The area under the brush sags like soft wax, in one smooth drop rather than separate drips.
Stirred coffee: Twirl over the cup at Radius 0.25 and Strength 0.5. At full Strength the center turns up to half a circle, which is enough to drag latte art into a spiral.
How this liquify tool works
There's one brush, and you place it with its settings instead of painting by hand. Its pull is full in the middle and fades smoothly to nothing at the rim, and it stays round whatever shape the frame is.
Each brush stops short of the pull that would fold the picture over itself. Even at full Strength the warp stays smooth, with no torn or doubled areas. A push moves the middle of the brush by up to 0.6 times Radius.
Can I liquify two places at once?
Not in one pass, since the page only has one brush. Save the first result, open the saved file and put the brush on the second spot, such as the other eye.
For a twist of more than half a turn, Swirl Effect turns the middle of the frame up to two full turns, and Fisheye Effect swells the whole frame at once.
Saving a liquified image or video
If you liquify in two or more passes, save every pass in between as PNG. Each JPG save compresses the picture again, and the losses pile up in the stretched areas, where detail is already thin.
On a video the brush stays where you put it while the footage moves through it, so a face can bulge or a street can twist for the whole clip.