Watercolor Effect
Watercolor effect for photos and video: soft washes of flat color with edges that stay clean. Free in the browser, and a clip comes out as MP4, WebM or GIF.
What does a watercolor effect do?
Watercolor is pigment suspended in water, laid on paper in thin, transparent layers. Its look comes from washes: broad areas of nearly flat color with clear borders where one wash meets the next.
A watercolor filter imitates that by merging a photo's fine detail into soft patches of color while it keeps the borders between them. Skin, sky and foliage end up as a few calm tones.
Painters build color in translucent glazes, one wash over another, and the 1997 computer-generated watercolor by Cassidy Curtis and colleagues at the University of Washington simulated each glaze with flowing water. This filter doesn't layer glazes or add paper texture. It reshapes the photo's own colors into washes.
How to turn a photo into a watercolor painting
Add a photo or a video and you'll find the Watercolour preset already set: Brush size 9, Sharpness 3 and Stretch 2. Brush size, from 2 to 20, controls how big the washes get.
Sharpness shapes the look more than anything else. Near 1, all eight sectors around a pixel count about equally, and you get something close to a plain blur. Around 3, the calmest sectors win often enough to hold the borders between washes. Above 8, the patches go flat and brushy, like the Oil preset.
Stretch at 2 pulls the washes out along the shapes, further than the Oil preset's 1 does. Below 1 the brush turns round and the color spreads evenly without streaking.
How the washes are made
Under the hood is an anisotropic Kuwahara filter, which smooths a picture while keeping its edges. At each pixel it averages eight sectors of the surrounding area and favors the calmest ones, so color spreads inside a shape and stops at its edge.
With Sharpness as low as the preset has it, neighboring sectors blend together rather than one winning outright, and the brush marks melt into washes.
Settings for a botanical study, a travel sketch, a soft sky and paper texture
For a botanical study, use Brush size 6, Sharpness 4, Stretch 0.65. Petals and leaves hold their outlines while the veins and texture inside them melt into one or two tones. A travel sketch works at Brush size 5, Sharpness 5, Stretch 0.85. Those smaller, crisper washes keep windows and signs readable, like a quick painting in a sketchbook.
A wet-on-wet sky or seascape wants Brush size 16, Sharpness 2, Stretch 0.35. The big, soft, round footprints run the colors into each other and only the strongest edges survive.
To get paper texture, save the painting as a PNG and load it into Film Grain Overlay. Set Mono, Blend mode Multiply and an Amount near 0.1 for a light speckle like the tooth of cold-pressed paper. If you'd like heavier paint from the same filter, Oil Painting Effect starts on the Oil preset.
Why does my watercolor look like a plain blur?
Your Sharpness is too low for the Brush size. Under 2, each pixel takes a nearly even average of its whole neighborhood, and that's exactly what a blur does. Raise Sharpness to somewhere between 3 and 5 and the borders between washes come back. If fine shapes like text or branches still dissolve, lower Brush size too.
A soft or out-of-focus photo doesn't have many edges to keep, so it reads as a blur at any setting. Sharp photos with clear shapes paint best.
Saving a watercolor
The washes are smooth gradients, not flat fills, so a GIF has to dither them. MP4 or WebM keep a painted clip smoother and smaller. If you're posting a still, WebP gives you the smallest file.
For print, save a PNG. A still is 2048 pixels on its long side, and from a 4:3 photo that prints at about 17 × 13 cm at 300 pixels per inch. That's enough for a card or a small frame.