Convert a photograph into a digital watercolor painting. The filter creates the illusion of pigment pooling on textured paper by combining non-linear smoothing with a high-frequency noise overlay.
The Kuwahara filter mechanism
The core of the effect relies on the Kuwahara filter. Instead of blurring pixels uniformly, the algorithm analyzes four overlapping quadrants around every pixel. It calculates the color variance in each quadrant and assigns the center pixel the mean color of the smoothest region. This prevents colors from bleeding across sharp borders. The outlines of subjects remain intact while interior colors blend softly.
Brush size and vibrance
A larger brush size creates broader strokes and removes more detail. A smaller brush size preserves finer shapes and works better for intricate scenes.
Because physical watercolor paint pools with high pigment density, the filter includes a vibrance control. Raising the vibrance increases color saturation before the smoothing pass, preventing skies or landscapes from looking muddy.
Paper texture overlay
A mathematically generated noise pattern blends over the painted output. This simulates the rough surface of cold-pressed watercolor paper. You can increase the opacity for a traditional painted appearance, or decrease it to zero for a smooth digital finish.